A Novel Push-Pull Method of Integrated Pest Management of Thrips and Tospoviruses on Peppers and Tomatoes

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Title:
A Novel Push-Pull Method of Integrated Pest Management of Thrips and Tospoviruses on Peppers and Tomatoes
Physical Description:
1 online resource (178 p.)
Language:
english
Creator:
Tyler-Julian, Kara
Publisher:
University of Florida
Place of Publication:
Gainesville, Fla.
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Thesis/Dissertation Information

Degree:
Master's ( M.S.)
Degree Grantor:
University of Florida
Degree Disciplines:
Entomology and Nematology
Committee Chair:
FUNDERBURK,JOSEPH E
Committee Co-Chair:
LEPPLA,NORMAN C

Subjects

Subjects / Keywords:
biocontrol -- frankliniella -- integrated -- kaolin -- management -- mulch -- organic -- orius -- pest -- reflective -- thrips -- thysanoptera
Entomology and Nematology -- Dissertations, Academic -- UF
Genre:
Entomology and Nematology thesis, M.S.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract:
Thewestern flower thrips (Frankliniella occidentalis) presents a major problem to farmers of fruiting vegetables by injuring fruits and vectoring Tomato spotted wilt virus. Attempts at controlling this species using calendar applications of broad-spectrum insecticides were ineffective. In contrast,ultra-violet reflective mulches effectively repel thrips and reduce the incidence of Tomato spotted wilt on tomatoes. Furthermore,combining multiple management tactics into a push-pull strategy is effective in other crop systems with other pests. The current study tested various combinations of ultra-violet reflective or black mulch, a kaolin clay spray, and companion plantings of Spanish needle (Bidens alba) and sunflowers (Helianthus annuus) for thrips management in tomatoes and peppers in Florida. Kaolin clay and ultra-violet reflective mulch both reduced thrips numbers on both crops and had a synergistic effect. Additionally, the planting of sunflowers as a companion plant increased thrips numbers on pepper plants, while Spanish needle reduced thrips numbers on tomatoes. Sunflowers attracted higher numbers of an effective predator (minute pirate bug, Orius insidiosus) to the fields than the crops alone. Companion plants of B. alba and ultraviolet-reflective mulch increased yield and decreased Tomato spotted wilt incidence on tomato. Ultraviolet-reflective mulch and kaolin increased yield of peppers. The results of the study show that these combinations can be successfully used as a push-pull method of thrips management in peppers and tomatoes.
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In the series University of Florida Digital Collections.
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Includes vita.
Bibliography:
Includes bibliographical references.
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Description based on online resource; title from PDF title page.
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This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility:
by Kara Tyler-Julian.
Thesis:
Thesis (M.S.)--University of Florida, 2013.
Local:
Adviser: FUNDERBURK,JOSEPH E.
Local:
Co-adviser: LEPPLA,NORMAN C.

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UFRGP
Rights Management:
Applicable rights reserved.
Classification:
lcc - LD1780 2013
System ID:
UFE0046378:00001


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A NOVEL PUSH PULL METHOD OF INTEGRATED PEST MANAGEMENT OF THRIPS AND TOSPOVIRUSES ON PEPPERS AND TOMATOES By KARA TYLER JULIAN A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE UNIVERSITY OF FLORIDA 2013

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2013 Kara Tyler Julian

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To Ramona Bunge, garden in peace.

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4 ACKNOWLEDGMENTS I owe a debt of gratitude to Dr.Fun derburk for giving me this amazing opportunity and for all of the support and guidance he has provided along my journey. I also want to thank Dr.Leppla for his thoughtful words of advice and guidance throughout the writing process. A debt of gratitude is a lso owed to Dr. Mrittunjai Srivistava, Dr. Ozan Demirozer, and Sarah McManus for their technical support on the project. Lastly I want to thank my husband, parents, and grandparents for being so understanding of my unavailability throughout the process. An d to Grandma Ramona Bunge thanks for passing on the love of agriculture and plants that courses through my veins.

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5 TABLE OF CONTENTS p age ACKNOWLEDGEMENTS ................................ ................................ ......................... 4 LIST OF TABLES ................................ ................................ ................................ ...... 7 LIST OF FIGURES ................................ ................................ ................................ .... 9 ABSTRACT ................................ ................................ ................................ ............. 11 CHAPTER 1 LITERATURE REVIEW ................................ ................................ ........................ 13 Thr ips and Tospoviruses ................................ ................................ ...................... 15 Control Methods ................................ ................................ ................................ ... 18 Companion Plantings a nd Conservation Biological Control ................................ 24 Ultraviolet Reflective Technologies ................................ ................................ ...... 26 Kaolin Particle Films ................................ ................................ ............................. 29 Push Pull Method ................................ ................................ ................................ 30 Primary Research Obj ectives ................................ ................................ ............... 31 2 EVALUATION OF A PUSH PULL STRATEGY FOR THE MANAGEMENT OF FRANKLINIELLA BISPINOSA (THYSANOPTERA: THRIPIDAE) IN BELL PEPPERS ................................ ................................ ................................ ......... 32 Introduction ................................ ................................ ................................ ......... 32 Methods ................................ ................................ ................................ ......... 36 Plot Establishment and Maintenance ................................ ............................. 36 Insect Sampling ................................ ................................ .............................. 38 Tomato Spotted Wilt Incidence ................................ ................................ ....... 38 Yield ................................ ................................ ................................ ............... 39 Data Analysis ................................ ................................ ................................ 39 Results ................................ ................................ ................................ ................ 40 Discussion ................................ ................................ ................................ ........... 49

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6 3 EVALUATION OF A NOVEL PUSH PULL METHOD FOR THE MANAGEMENT OF THRIPS AND TOSPOVIRUSES IN TOMATOES IN NORTH FLORIDA ..... 88 Introduction ................................ ................................ ................................ ......... 88 Materials and Methods ................................ ................................ ................... 95 Plot Establishment and Maintenance ................................ ............................. 95 Insect Sampling ................................ ................................ .............................. 96 Yield ................................ ................................ ................................ ............... 97 Data Analysis ................................ ................................ ................................ 97 Results ................................ ................................ ................................ ................ 98 Discussion ................................ ................................ ................................ ......... 111 4 AN EVALUATION OF A PUSH PULL METHOD TO MANAGE TOMATO SPOTTED W ILT VIRUS ON TOMATOES IN NORTH FLORIDA ................... 151 Introduction ................................ ................................ ................................ ....... 151 Materials and Methods ................................ ................................ .................. 152 Results and Discussion ................................ ................................ ................. 153 5 CONCLUSIONS AND FUTURE DIRECTIONS ................................ .................. 161 R E F E R E N C E S ................................ ................................ ................................ ...... 164 B I O G R A P H I C A L S K E T C H ................................ ................................ .................... 1 79

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7 LIST OF TABLES Table page 2-1 Thrips larvae to adult ratios on peppers and sunflowers in 2011 ................... 62 2-2 Thrips larvae to adult ratios on peppers and sunflowers in 2012 ................... 63 2-3 Prey to predator ratios on peppers and sunflowers in 2011 ........................... 64 2-4 Prey to predator ratios on peppers and sunflowers in 2012 ........................... 65 25 F-values for treatment effects in the ANOVAs on thrips and Orius in peppers in 2011 ........................................................................................................... 66 26 F-values for treatment effects in the ANOVAs on thrips and Orius in peppers in 2012 ........................................................................................................... 67 27 F-values for treatment effects in the ANOVAs on thrips and Orius in sunflowers in 2011 ......................................................................................... 69 2-8 F-values for treatment effects in the ANOVAs on thrips and Orius in sunflowers in 2012 ......................................................................................... 70 29 Mean numbers and weights and ANOVA F-Values of pepper yield in 2011 .. 71 210 Mean numbers and weights and ANOVA F-Values of pepper yield in 2012 .. 73 31 Thrips larvae to adult ratios on tomatoes and B. alba in 2011 ..................... 121 3-2 Thrips larvae to adult ratios on tomatoes and B. alba in 2012 ..................... 122 33 Prey to predator ratios on tomatoes and B. alba in 2011 ............................. 123 3-4 Prey to predator ratios on tomatoes and B. alba in 2012 ............................. 124 35 F-values for treatment effects in the ANOVAs on thrips and Orius in tomatoes in 2011 ......................................................................................................... 125 36 F-values for treatment effects in the ANOVAs on thrips and Orius in tomatoes in 2012 ......................................................................................................... 128 3-7 F-values for treatment effects in the ANOVAs on thrips and Orius in B. alba in 2011 ............................................................................................................. 132 3-8 F-values for treatment effects in the ANOVAs on thrips and Orius in B. alba in 2012 ............................................................................................................. 134

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8 3 9 Mean numbers and weights and ANOVA F Values of tomato yield in 2011 136 3 10 Mean numbers and weights and ANOVA F Values of tomato yield in 2012 139 4 1 F values for treatment effects in the ANOVAs on Tomato spotted wilt incidence in tomatoes in 2011 ................................ ................................ ..... 156 4 2 F values for treat ment effects in th e ANOVAs on Tomato spotted wilt incidence in tomatoes in 2012 ................................ ................................ ..... 157

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9 LIST OF FIGURES Figure page 2 1 Season distributi on of thrips in different companion plant conditions on peppers in 2011 ................................ ................................ ................................ 76 2 2 Season distribution of thrips in different companion plant conditions on peppers in 2012 ................................ ................................ ................................ .. 77 2 3 Season d istribution of Orius in different companion plant conditions on peppers in 2011 ................................ ................................ ................................ 78 2 4 Season distribution of Orius in different companion plant conditions on peppers in 2012 ................................ ................................ ................................ 79 2 5 E ffect of mulch and kaolin on thrips in peppers in 2011 ................................ .... 80 2 6 Effect of mulch on thrips in peppers in 2012 ................................ ...................... 8 1 2 7 Effect of k aolin clay on thrips in peppers in 2012 ................................ ................ 82 2 8 Effect of mulch and kaolin on Orius in peppers in 2011 ................................ ..... 83 2 9 Effect of mulch on Orius in peppers in 2012 ................................ ...................... 84 2 10 Effect of kaolin on Orius in peppers in 2012 ................................ ...................... 85 2 11 Effects of mulch and kaolin on thrips and Orius on sunflowers in 2011 ............. 86 2 12 Effects of mulch and kaolin on thrips and Orius on sunflowers in 2012 .............. 87 3 1 Season distribution of thrips in different companion plant conditions on tomatoes in 2011 ................................ ................................ ............................. 143 3 2 Season distribution of thrips in different companion plant conditions on tomatoes in 201 2 ................................ ................................ ............................. 144 3 3 Season distribution of thrips larvae in different treatment conditions on tomatoes in 2011 ................................ ................................ ............................. 145 3 4 Season distribution of thrips larvae in different treatment conditions on t omatoes in 2012 ................................ ................................ ............................. 146 3 5 Effect of kaolin on thrips in tomatoes in 2011 ................................ .................. 147 3 6 Effect of kaolin on thrips in tomatoes in 2012 ................................ .................. 148

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10 3 7 Effect of mulch on thrips in tomatoes in 2011 ................................ .................. 149 3 8 Effect of mulch on thrips in tomatoes in 2012 ................................ ................... 150 4 1 Effect of companion plants on Tomato spotted wilt incidence on tomatoes ..... 158 4 2 Effect of mu lch on Tomato spotted wilt incidence on tomatoes ....................... 159 4 3 Effect of kaolin on Tomato spotted wilt incidence on tomatoes ....................... 160

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11 Abstract of Thesis Presented to the Graduate School of the Uni versity of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Science A NOVEL PUSH PULL METHOD OF INTEGRATED PEST MANAGEMENT OF THRIPS AND TOSPOVIRUSES ON PEPPERS AND TOMATOES By Kara Tyler Julian December 2013 Chair: Joe Fund erburk Major: Entomology and Nematology The western flower thrips ( Frankliniella occidentalis ) presents a major problem to farmers of fruiting vegetables by injuring fruits and vectoring Tomato spotted wilt virus Attempts at controlling this species us ing calendar applications of broad spectrum insecticides were ineffective. In contrast, ultra violet reflective mulches effectively repel thrips and reduce the incidence of Tomato spotted wilt on tomatoes Furthermore, combining multiple management tactics into a push pull strategy is effective in other crop systems with other pests. The current study tested various combinations of ultra violet reflective or black mulch, a kaolin clay spray, and companion plantings of Spanish needle ( Bidens alba ) and sunflo wers ( Helianthus annuus ) for thrips management in tomatoes and peppers in Florida. Kaolin clay and ultra violet reflective mulch both reduced thrips numbers on both crops and had a synergistic effect. Additionally, the planting of sunflowers as a companion plant increased thrips numbers on pepper plants, while Spanish needle reduced thrips numbers on tomatoes. Sunflowers attracted higher numbers of an effective predator (minute pirate bug, Orius insidiosus ) to the fields than the crops alone. Companion plan ts of B. alba and ultraviolet reflective mulch increased

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12 yield and decreased Tomato spotted wilt incidence on tomato. Ultraviolet reflective mulch and kaolin increased yield of peppers. The results of the study show that these combinations can be successfu lly used as a push pull method of thrips management in peppers and tomatoes

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13 CHAPTER 1 LITERATURE REVIEW Agriculture is one of the most important facets of the economy in terms of monetary value and the value it serves by providing jobs and food. Flor ida specifically ranks second in value of vegetable production, producing 45% ( $631 million) of fresh market tomatoes and 46% of total bell peppers ($296 million) in the United States (FDACS 2011). While growing crops to feed the world growers are forced to contend with many factors that challenge their ability to grow food in an efficient and profitable manner. Insect pests are a major force that threatens the livelihood of farmers and the health of the food industry. Thrips are one of the major pest gro ups affecting vegetable growers. There are over 6000 species of thrips (Order Thysanoptera) worldwide, and 87 are considered pests of commercial crops (Mound 1997). Injury to leaves, fruits, and flowers is caused during the feeding process, in which the ad ults and larvae pierce the plant with the mandible and extract the contents of ruptured cells. Additional injury to leaves, flowers, and fruits may occur during the oviposition process when the egg is ergence of the larva (Childers, 1997). Numerous species also vector pathogens that cause disease in addition to the mechanical damage they inflict on the plants (OEPP/EPPO, 2004) In Florida, the Western flower thrips ( Frankliniella occidentalis Pergande) is an invasive species of thrips which injures leaves, fruits and flowers of multiple vegetable crops (Childers 1997) and vectors Tomato Spotted Wilt Virus (OEPP/EPPO 2004) The loss to farmers from this disease is estimated at $1 billio n annually (Goldba ch and Peters 1994). In the past and present, farmers have dealt with thrips and other pests using multiple applications of broad spectrum pesticides (Pimentel et al. 1991). While

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14 broad spectrum insecticides were originally successful there are negative ef fects which encourage new management strategies. These include: the development of resistance in insects to the pesticides (Roush and Tabashnik 1990); the unintentional decimation of other, potentially beneficial arthropods (Pimentel et al. 1991 Epstein e t al. 2000 ); the resurgence of pests after pesticide applications (Hardin et al. 1995 Summers and Stapleton 2002a ); secondary p est outbreaks of pests that previously were not problematic (Morse 1998); harmful effects on the environment and native wildlife (Davidson 2004); the endangerment of the health and lives of humans (Pimentel 2009). In addition to these disadvantages, pesticides do not always prevent disease transmission (Pinese et al. 1994, Summers and Stapleton 2002a Summers et al. 2004 ) and despi te the increase of pesticide use there has been an increase, rather than a decrease in pest damage (Pimentel et al. 1991). Pesticides cost an estimated $7.9 billion annually in public health effects, pesticide resistance, crop losses caused by pesticides, avian mortality due to pesticides and groundwater contamination (Pimentel 2009). This misuse, overuse, and unnecessary use of pesticides resulted in the birth of integrated pest management in 1976 ( Stern et al. 1959, Metcalf 1980). The spread of the weste rn flower thrips and species of tospoviruses resulted in the world wide destabilization of established integrated pest management programs for many crops (Morse and Hoddle 2006), and this included fruiting vegetables grown in Florida. One of the contributi ng factors to the problems produced by this pest is the propensity of the western flower thrips to quickly develop resistance to many classes of pesticides ( Gao et al. 2012). Several technol ogies have been developed which circumvent these

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15 pesticide resista nces. These technologies include, but are not limited to: spinosads and other new insecticides (Funderburk 2009); UV reflective mulch technologies (Stavisky et al. 2002 Reitz et al. 2003 ); companion plants (Kasina et al. 2006; Lopez and Shepard 2007); par ticle films such as kaolin clay (Glenn et al. 1999, Knight et al. 2000); and biocontrol using natural enemies (Funderburk et al. 2000). These methods can be used alone or in combination with other methods including the use of reduced risk insecticides as p art of an integrated pest management plan. A recently developed technology combines both repellant and attractive plants in a field to repel pest insects from the crop and attract them to a non crop plant on which they can be controlled (Khan et al. 2001). This method is effective in reducing damage to maize plants from stemborers in Kenya and may be promising for use with other crops and pests. The current study evaluates a new use of push pull technology combining ultraviolet reflective mulch (push), kaol in clay sprays (push) and companion plants (pull) to manage thrips on peppers and to matoes. Thrips and Tospoviruses In Florida there are two common native species of thrips found in the flowers of crops. These are the eastern flower thrips ( Frankliniella tritici Fitch) which is the common species in North Florida (Reitz 2002) and the Florida flower thrips ( Frankliniella bispinosa Morgan) which is the common species in South and Central Florida (Hansen et al. 2003). Other species of thrips found on Florida vegetable crops in much lower numbers include the tobacco thrips ( Frankliniella fusca Hinds) in N orthern Florida, and Frankliniella schultzei (Trybom) in Central and S outhern Florida (Hansen et al. 2003). In addition to these native species of thrips, ther e have been a few recent Thysanopteran

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16 invaders in Florida including the chili thrips, Scirtothrips dorsalis (Hood), Megalurothrips mucunae (Priesner) on legumes (Diffie et al. 2008) and the melon thrips, Thrips palmi Karny. Whereas these aforementioned th rips are not of major concern on tomato and pepper crops, one invasive species is present which poses a major threat to Florida farmers: the western flower thrips ( Frankliniella occidentalis Pergande) The western flower thrips is n ative to the S outhweste rn United States but was global trade in gr eenhouse plants (Kirk and Terry 2003). While F. occidentalis has been established in northern Florida since the early 1980s, it did not become an economic problem in central and southern Florida until 2005 (Frantz and Mellinger 2009). The potential damage posed by the western flower thrips is twofold: aesthetic damage caused by excessive levels of injury due to feeding and ovip osition, and plant disease caused by Tospovirus spread by the western flower thrips. Worldwide the western flower thrips is the major vector of Tomato spotted wilt virus and Impatiens necrotic spot virus and it is also a vector of Chrysanthemum stem necros is virus Groundnut ringspot virus and Tomato chlorotic spot virus ( Pappu et al. 2009 Webster et al. 2011 ) Frankliniella bispinosa, F. tritici, and F. occidentalis all exhibit thigmotactic behavior. For this reason they are found aggregating in flowers as adults and as larvae are found in flowers and on fruits, often choosing to hide under the calyx on the fru it or in places of contact between fruits a nd stems or leaves (Kirk 1997). These polyphagous species feed and reproduce on many species of cultivated and uncultivated plants. The adults feed on the pollen and flower tissues and the female lays individual e ggs in the small developing fruit of some crops such as tomato. After the egg hatches a small

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17 dimple often remains on the developing fruit which may or may not be surrounded by a halo. This dimple will remain on the developing fruit long after the egg hatc hes (Salguero Navas et al. 1991). In addition to this initial oviposition injury, the larvae will continue to feed on the fruit causing an additional injury known as al.2006). Although the injury to the fruits by the F. occidentalis c an be aesthetically damaging causing cull out and downgrading (Funderburk 2009), a more serious threat is the vectoring capability of F. occidentalis of various tospoviruses. For Florida vegetable growers the most serious and widespread disease vectored by F. occidentalis is Tomato spotted wilt virus estimated to cost farmers US$1 billion in crop losses annually (Goldbach and Peters 1994). Eight species of thrips are capable of transmitting Tomato spotted wilt virus: F. bispinosa, F. cephalica, F. fusca Fr ankliniella intonsa ( Trybom), F. occidentalis F. schultzei, Thrips setosus Moulton, and Thrips tabaci Lindeman, and S. dorsalis. (Pappu et al. 2009). There are 19 species of tospovirus, of which T omato spotted wilt virus is the type species. All of the to spoviruses are spread exclusively by t hrips. Tomato spotted wilt infects 900 species of plants, cultivated and uncultivated. The virus manifests as necrotic spots, streaks or rings on the leaves or fruits. The severity of the symptoms can range from flecks on the fruit to necrotic lesions. Tomato spotted wilt has a mutual relationship with F. occidentalis : thrips larvae have a higher survival rate and develop more quickly on infected plants (Stumpf and Kennedy 2007). Additionally, plants infected with the v irus are more attractive to thrips which preferentially feed and oviposit on the infected plants over uninfected plants (Maris et al. 2004).

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18 Tospoviruses are spread by the thrips in two stages: Primary infection and secondary infection. Tospoviruses are fi rst acquired by the larvae while feeding on an infected plant. Upon becoming adults, these infected thrips can transmit tospoviruses to uninfected plants within seconds of feeding on them. The adults persistently transmit once they have acquired the tospov irus as larvae. Primary infection refers to infection that occurs when a viruliferous adult capable of transmitting a tospovirus arrives in a new field, and begins to feed on the plants thereby infecting them with the disease. Secondary spread occurs when the adults reproduce on the infected plants, and the larvae acquire the tospovirus. After developing to adult, the thrips transmit the virus to other uninfected plants with in the same field (Momol et al. 2004). Pesticides do not effectively reduce primary spread due to the small amount of feeding time required for i nfection to occur (Momol et al. 2004). Thrips are able to feed and transmit the disease faster than they are killed by the pesticide. Therefore repellant strategies are needed to prevent the adul ts from feeding. The most effective way to reduce secondary spread is by controlling larvae. The majority of infections in northern Florida tomatoes are caused by primary infection (Momol et al. 2004). Control M ethods The population attributes of reproduct ion on numerous plant species in many plant families, high fecundity, rapid generation time, and high dispersal capability provide for an extraordinary ability for F. occidentalis to exploit ephemeral crop resources. Populations are able to continue rapid population buildup despite the attempts to control with repeated application of conventional insecticides (Funderburk et al. 2000). Farmers worldwide commonly employ calendar applications of broad

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19 spectrum insecticides in an effort to control thrips. Unfor tunately, this method is not successful and, in addition to economic damage from the cost of overus ing pesticides, farmers suffer losses of crops to disease epidemics and direct damage from high populations ( ion for F. occidentalis resistance to numerous insecticides; resurgence of F. occidentalis populations as a result of natural predators and native competitor thrips being eliminated; and replacement by various other pests (Reitz and Funderburk 2012). Fra nkliniella occidentalis have a propensity for developing resistance to many classes of insecticides. The means by which F. occidentalis develops pesticide resistances are reviewed by Gao et al. (2012). The polyphagous nature of thrips likely resulted in t heir predisposition to evolve resistances through several metabolic detoxification pathways. These pathways allowed the insect to develop an array of resistances when traveling from host to host and encountering unknown defensive chemicals ( Ros enheim et al. 1996 ) This adaptation continues to benefit F. occidentalis as it enables them to ef ficiently develop resistances through these same pathways to numerous classes of insecticides ( Zhao et al. 1995 Broadbent and Pree 1997 ) including organ ophosphate, carbamate, pyrethroid, and organochlorine insecticides (Immaraju et al. 1992). The resistance to pyrethroids through these metabolic detoxification pathways has occurred worldwide and occurs rapidly ( Immaraju et al. 1992 Zhao et al. 1995 Broadbent and Pree 1997 S eaton et al. 1997 Herron and Gullick 2001 Espinosa et al. 2002, Thalavaisundaram et al. 2008 Frantz and Mellinger 2009 ) Resistance to insecticides can derive from more than one trait, can develop from more than one pathway and multiple pathways can combine to contribute to each pesticide resistance

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20 ( Jensen 1998 ) These many factors have led to a large number of modes by which F. occidentalis has developed resistances to many pesticides and combinations thereof. Additionally, F. occidentalis maintain these resistances for long periods of times in the absence of pesticides without any obvious fitness disadvantages ( Robb 1989 Brdsgaard 1994 Kontsedalov et al. 1998, Biel za et al. 2008 ). Other characteristics of thrips which render foliar sprays of pesticides ineffective are their cryptic behaviors and their ability to pupate in the soil (Berndt et al. 2004). Many factors render pesticides ineffective in the short or long term in controlling thrips and tospoviruses. Furthermore, control approaches affect the lives of other non target organisms. For these reasons, alternative methods of managing thrips are desirable. These methods should be safe for beneficial insects, effic acious for thrips and ot her pests, economical, and utilize the behaviors of the thrips and their natural enemies all within the scope of integrated pest management (Stern et al. 1959). The adults of the two native thrips, F. tritici and F. bispinosa speci es do not damage the fruiting vegetables and these native species also contribute to the control of F. occidentalis by out competing F. occidentalis Even densities of 20 25 adults per flower of the two native species do not result in damage to tomato, pep per, or eggplant (Funderburk 2009); however, the econo mic threshold of F. occidentalis adults is one adult per tomato flower or six adults per pepper or eggplant flower due to the damage they cause and their vectoring capabilites(Funderburk et al. 2011a, F underburk et al. 2011b). Using these thresholds to decide when to take action can preserve native species of thrips which can act as a natural barrier against F. occidentalis in the field.

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21 Most broad spectrum synthetic insecticides including pyrethroids neonico tinoids, organophosphates, and carbamates kill the native species of thrips that outcompete F. occidentalis (Hansen et al. 2003, Reitz et al. 2003, Srivistava et al. 2008), thereby leading to dramatic large scale shifts in thrips d emographics (Fra ntz and Mellinger 2009). Broad spectrum insecticides can directly enhance the rate of increase of F. occidentalis populations. The pyrethroid acrinathrin increases the fecundity of resistant F. occidentalis females, and survivorship, developmental rates, a nd longevity of progeny is as great, or greater, than for progeny of susceptible females (Bielza et al. 2008). Synthetic broad spectrum insecticides not only disrupt F. occidentalis management, they also disrupt management of other pests including spider m ites, whiteflies, and leafminers, by eliminating natural enemies of those pests (Armenta et a l. 2003, Gonzalez Zamora et al. 2004). In recent years, due to the harmful unintended side effects of broad spectrum pesticides, growers have begun using natural and reduced risk insecticides. The spinosyn class is the most efficacious of these insecticides providing a greater level of control of F. occidentalis than all other currently available reduced risk and broad spectrum insecticides (Funderburk 2009). Due t o the high vagility of F. tritici and F. bispinosa spinosyns are effective against F. occidentalis while affecting the two native species of thrips to a lesser degree wh ich can assist in preserving natural competition (Reitz et al. 2003). Unfortunately F. occidentalis has developed some level of resistance to spinosyns in pockets in Florida (Weiss et al. 2009) A biologically based integrated pest management program is fundamental in preventing the development of insecticide resistance, resurgence of F. oc cidentalis

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22 populations, and replacement with nontarget pest damage (Weiss et al. 2009). Evidence suggests that the conservation biological control component of the integrated pest management program is the most effective way to manage thrips in pepper and eggplant (Funderburk et al. 2000, Reitz et al. 2003 Funderburk 2009 ). Many predaceous arthropod groups help to suppress thrips populations. Species of Anthocoridae are the most important worldwide predators of thrips. Within this family are minute pirate bugs with two species in Florida, Orius pumilio (Champion) and Orius insidiosus (Say), the key natural enemies of thrips in eggplant and pepper (Funderburk et al. 2000). Although the minute pirate bugs are not present in high numbers in tomato fields, they are the only predatory heteropteran consistently found in tomato fields, in low numbers (Kiman and Yeargan 1985). The minute pirate bugs feed on all three species of thrips, but they prey preferentially on the adults of the F. occidentalis over the adults of the non damaging native thrips species (Reitz et al. 2006). This aspect of feeding makes the minute pirate bugs a valuable tool for managing F. occidentalis Frankliniella tritici and F. bispinosa are smaller and move around more frequently and at a fa ster pace than F. occidentalis This may be the reason for the preferential fee ding behavior (Baez et al. 2004, Reitz et al. 2006). The thrips larvae are the preferred life stage for predation (Baez et al. 2004). Approximately one adult minute pirate bug for every 180 thrips is sufficient for suppression of the populations of thrips. At a ratio of about one predator to 40 thrips, thrips populations are controlled (Funderburk et al. 2000). Natural populations of minute pirate bugs are highly vagile (Ramacha ndran et al. 2001). The adults rapidly invade pepper and eggplant fields in Florida in sufficient numbers to control F. occidentalis

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23 adults and larvae, but they must be conserved with cautious insecticide use (Funderburk 2009). Usually, natural populations are not sufficient in tomato to provide control of F. occidentalis (Baez et al. 2011). Other thrips predators include the big eyed bugs (Family Lygaeidae), damsel bugs (Family Nabidae), lacewings (Family Chrysopidae), predatory thrips (primarily in the fa mily Aeolothripidae), and predatory mites (Family Phytoseiidae). Natural populations of these predatory groups do not typically invade fields of fruiting vegetables in sufficient numbers to suppress thrips populations. There is potential to attract minute pirate bugs into these fields using habitat management strategies such as companion plantings. Minute pirate bugs are known to supplement their diet with plant materials such as pollen and can develop and reproduce on a diet of pollen and nectar alone for up to six months (van den Meiracker and Ramakers 1991). Their survival rate, life span and reproduction rate are higher, and the developmental time is shorter on a diet of thrips and pollen than on a diet of thrips alone (Kiman and Yeargan 1985). Minute p irate bugs are also more abundant where pollen is present and will migrate in the absence o f pollen (Malais and Ravensburg 1992). In a study by Lundgren et al. 2009 the addition of plants with suitable oviposition sites and refuges from natural enemies wa s associated with lower herbivore densities and higher predator densities on the target plant. The densities of minute pirate bugs in this study were higher on the target plants in polycultures than in monocultures. Minute pirate bug nymphs also experience d higher fitness in diverse fields (Lundgren et al. 2009). Minute pirate bugs have the ability to rapidly recolonize plots treated with

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24 insecticides (Ramachandran et al. 2001) and this ability could be enhanced with the addition of companion plantings in w hich the minute pirate bugs could take shelter to avoid insecticides and then later recolonize the sprayed plots. Companion P lantings And Conservation Biological Control Conservation biological control involves the use of methods which act to conserve nat ural enemies of pests in the environment. One of these methods is habitat management. Habitat management is the alteration of farmland or the general landscape in such a way as to provide resources for natural enemies such as food, alternative prey or host s, and shelter from adverse conditions (Landis et al. 2000). The diversification of agricultural systems using native plants can benefit both integrated pest management programs and the conservation of arthropods in a region (Kogan and Lattin 1993). There are many methods of diversifying agricultural systems to en hance natural enemies. These include companion, refugia, or banker plantings, intercrops, strip crops, conservation strips, beetle banks and polycultures in general. These different types of struct ural diversification are beneficial in different crop and pest situations, but overall increased habitat structure diversification is associated with a significant increase in natural enemy ab undance (Langellotto and Denno 2004). In an early study on enhan cing natural enemies in cotton in Oklahoma, sorghum strip crops in cotton fields increased predator numbers in the cotton and were associated with an increased yield of cotton (Robinson et al. 1972). In a later study, strip cropping of Lucerne ( Medicago sa tiva ) with cotton also increased the numbers of predat ors of Helicoverpa spp. (Mensah 1999). Habitat diversification and the presence of flowering weeds successfully increased the numbers of natural enemies and

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25 decreased numbers of aphids, whiteflies, and leafhoppers i n cotton (Showler and Greenburg 2002, Ghodani et al. 2009). The suppression of these pests and the injury they cause using habitat diversification was superior to suppression using insecticides (endosulfan and monocrotophos). The diversificati on also led to increased yield of cotton (Ghodani et al. 2009). Strip crops of corn and weeds also increase d the numbers of natural predators and parasitoids of the African bollworm ( Heliothis armigera ) on haricot bean (Abate 1991). This effect is variable depending upon the strip crop used and the natural enemy concerned. In this case, corn and weed strip crops both increased the numbers of tachinid parasitoids, whereas only weed strip crop s increased the numbers of the Tiphia spp. predatory wasps (Abate 1 991). Intercropping, planting two different crops or a crop and noncrop alternating in the same row has also been a successful form of habitat manageme nt (Tonhasca 1993, Ponti et al. 2007). Intercropping soybean and corn increased the numbers of natural e nemies compared to planting these crops in monocultures. In a similar study, intercropping buckwheat and mustard with broccoli decreased cabbage aphid ( Brevicoryne brassicae L.) pressure and increased the numbers of natural enemies (Ponti et al. 2007). Hab itat diversification also effectively reduces numbers of pests and increases numbers of natural enemies in non crop agricultural systems. Conservation strips (beetle banks and flowering insectory strips) successfully increased predator, parasitoid and alte rnative prey abundance in golf course fairways. Predation on Agrotis ipsilon Hufnagel was greater in fairways with conservation strips (Frank and Shrewsbury 2004).

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26 Planting flowering forbs around ornamental shrubs in urban environments increased parasitism rates on bagworm by 71% (Ellis et al. 2005). Plantings of flowering plants around ornamental plants Euonymus fortunei also increased numbers of natural enemies (Rebeck et al. 2005). Various plant species offer habitat for important natural enemies of th ri ps and other insects (Landis et al. 2000). Numerous plant species attract enough enemies to control F. occidentalis populations on green beans and medicinal plants (Kasina et al. 2006, Lopez and Shepard 2007). Intercrops of baby corn, Irish potato and sunf lowers with French beans in Kenya reduced populations of F. occidentalis and increased populations of Orius spp. compared with a monocrop (Nyasani et al. 2012). In Florida, Bidens alba sunflowers, Wedeli a trilobata and two species of clover are hosts for minute pirate bug and other nat ural enemies (Bottenberg et al. 1999), and plantings near crops of fruiting vegetables increase biological control of thrips (Frantz and Daucus carota Ammi ma jus are good hosts for Orius species (Shirk et al. 2011). Additionally, these and other wild plant species around fields host the non damaging native thrips species (Northfield et al. 2008) that are competitors of F. occidentalis (Paini et al. 2008). Comp anion plantings of these species are not source s for damaging populations of F. occidentalis as they are outcompeted by the native thrips species and they suffer preferential predation by minute pirate bug s. These plant species can be effective companion p lants, intercrops or strip crops in fields to increase natural predators of thrips and reduce thrips numbers.

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27 Ultraviolet Reflective Technologies Thrips, like other insects, locate host plants primarily through a combination of visual cues, with anthophi lous thrips att racted to colors of flowers. Frankliniella occidentalis are attracted to spectral radiation in the ultraviolet range (~365 nm) and in the yellow green r ange (~540 nm) (Matteson et al. 1992). The yellow green sensitivity plays a role in long distance orientation to plants, and the ultraviolet sensitivity assists with distinguishing flowers. Consequently, increasing the reflectivity in the ultraviolet range of the spectrum repels thrips. The ultraviolet reflective mulches available for the rais ed bed plastic mulch production system effectively repel colonizing adults of F. occidentalis and this repellency reduces the primary and secondary spr ead of Tomato spotted wilt. The use of ultraviolet reflective mulch also reduces the influx of the nativ e thrips, but not disproportionately to reductions in F. occidentalis (Reitz et al. 2003 Momol et al. 2004 ). Ultraviolet reflective mulches are used in many crops. These mulches are used on both organic and conventional farms as part of an integrated pa st management program. The ultraviolet reflective mulches work by reflecting as much as 86% of incoming short wave light (Summers et al. 2004) which repels incoming insects and reduces the number of insects alighting on plants (Kring and Schuster 1992). Ul traviolet reflective mulches are successful in different crops including corn (Summers and Stapleton 2002a), zucchini (Pinese et al. 1994), cantaloupe (Stapleton and Summers 2002), cucumber (Summers and Stapleton 2002b Rapando et al. 2009) summer squash ( Brown et al. 1996, Murphy et al. 2008), watermelon (Farios Larios and Orozco Santos 1997, Simmons et al. 2010), pumpkins (Brust 2000, Summers and

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28 Stapleton 2002b), peppers (Reitz et al. 2003, Kring and Schuster 1992), and tomatoes (Momol et al. 2002 Riley and Pappu 2004 ) to name a few. In addition to thrips, many other key pests of these crops ar e controlled successfully by ultraviolet reflective mulches including whiteflies (Summers et al. 2004, Simmons et al. 2010), aphids (Pinese et al. 1994, Stapleton and Summers 2002, Summers et al. 2010), leafhoppers (Summers and Stapleton 2002a), plant bugs (Rhainds et al. 2001) and beetles (Andino and Motsenbocker 2004). The broad range of pest s repelled by the mulch make ultraviolet reflective mulch ideal for crop systems that are infested by numerous pest species. In addition to repelling insects the mulch also reduces incidence of disease (Kring and Schuster 1992, Brust 2000, Stapleton and Summers 2002, Murphy et al. 2008 Rapando et al. 2009), increases yield (F arios Larios and Orozco Santos 1997, Pinese et al. 1994, Reitz et al. 2003, Murphy et al. 2008), improves crop growth (Pinese et al. 1994, Andino and Motsenbocker 2004 Summe rs et al. 2004) provides monetary savings from reduced crop losses, labor and ins ecticides (Pinese et al. 1994 Brust 2000, Riley and Pappu 2004), and can be used in combination with other management strategies such as insecticides (Momol et al. 2002, Reitz et al. 2003, Riley and Pappu 2004, Nyoike et al. 2010) and disease resistant pl ants (Riley and Pappu 2004, Rapando et al. 2009, Simmons et al. 2000). Ultraviolet reflective mulches are most effective early in the crop season before the plant canopy begins to cover the mulch, thereby reducing the surface area available for reflectan ce (Reitz et al. 2003 Momol et al. 2004 ). Application of certain fungicides and other pesticides reduces the ultraviolet reflectance and hence the efficacy of the

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29 mulch. A single application of copper and mancozeb fungicide can reduce the reflectance by a pproximately 49% (Reitz, unpublished). Kaolin Particle Films Kaolin clay is a particle film composed of aluminosilicate mineral that can be applied to plants as a form of protection. The clay leaves a white residue that can be washed from the fruits and t he plant. Kaolin films are compatible with organic methods and can suppress pests while benefiting the plant in other ways. Particle film treatments control arthropod pests through numerous processes including: reducing the longevity of the pest (Knight et al. 2000); reducing mating success (Knight et al. 2000), oviposition rate (Knight et al. 2000; Larentzaki et al. 2008) and hatch rate (Larentzaki et al. 2008); to grasp plant surfaces (Puterka et al. 2005, Hall et al. 2007) and to recognize host plants (Puterka et al. 2003); and even increasing mortality (Larentzaki et al. 2008). Foliar applications of kaolin clay reduce populations of various pests and the damag e they cause including obliquebanded leafrollers on fruit trees (Knight et al. 2000); fruit flies on fr uit trees (Mazor and Erez 2004, Saour and Makee 2004); boll weevils on cotton (Showler 2002); silverleaf whiteflies on melons (Liang and Liu 2002); pear psylla (Puterka et al. 2005); citrus psyllids (Hall et al. 2007); glassy winged sharpshooters on grapes (Puterka et al. 2003); weevils, leafhoppers, sawflies, scale insects, moths, and aphids on apples (Marko et al. 2008); and moths, Japanese beetles, plan t bugs and stink bugs on peach trees (Lalancette et al. 2005). Applications of kaolin clay can also be used to control thrips. Laboratory studies revealed numerous mechanisms by which the kaolin suppresses populations of T.tabaci

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30 on onions including reduc ing feeding, increasing mortality, reducing hatch rate, and increasing development time (Larentzaki et al. 2008). Kaolin clay applications also reduce populations of Frankliniella thrips within the canopy of rabbiteye blueberry plants while also increasing yield (Spiers et al. 2004). In addition to suppressing pests, kaolin clay reduces the number of plants infected with disease (Glenn et al. 2001 Tubajika et al. 2007, Reitz et al. 2008), increase s yield (Spiers et al. 2004 Lalancette et al. 2005 Reitz et al. 2008), and reduce s heat stress and sunburn damage in fruit trees (Glenn et al. 2001, Glenn et al. 2002). Despite all of these benef its, kaolin clay has a few weaknesses It is degraded by rain and must be reapplied throughout the season in order to remain effective (Showler 2002 Hall et al. 2007 ) It can also reduce numbers of natural enemies thus causing an increase in some pest numbers (Marko et al. 2008). The hydrophobicity and deposit density of the clay are important factors for disease managem ent and some deposit densities do not prevent disease effectively which must be taken into account (Lalancette et al. 2005). Push Pull Method A novel approach to pest management is the push pull or stimulo deterrent method. This method was developed in Ke nya for use on subsistence farms. The method is based on behavioral manipulations involving an unattractive stimulus (push) to repel insects from crops and an attractive (pull) stimulus to attract the pests to an alternate source from which they can be rem oved or controlled (Cook et al. 2007). This method is successful in Kenya in a maize crop system. Stemborers are pushed from the maize using repellant molasses grass and desmodium and pulled to the attractive

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31 Napier grass. Th is particular combination signi ficantly increased yield, increased parasitism of stemborers by parasitoids attracted to the molasses grass, and reduced damage to maize by the competitiv e weed Striga (Khan et al. 2001, Khan et al. 2008a). This system is estimated to be profitable for sma ll farms in Africa (Khan et al. 2008b). While this example involved the use of companion plants as the push and the pull, other potential methods that have been used are chemical odors for thrips on onions (Van Tol et al. 2007) and light traps for wood bo ring beetles (Pawson and Watt 2009). Apart from these studies and despite the success in the maize systems in Kenya, very little research has been done using push pull methods to control pests. Primary Research Objectives The primary objectives of the cu rrent study were to (1) evaluate the effects of a push pull method of thrips management on thrips, Orius spp. and yield in bell peppers; (2) evaluate the effects of a push pull method of thrips management on thrips, Orius spp. and yield in tomatoes; (3) evaluate the effects of a push pull method of thrips management on the incidence of Tomato spotted wilt on tomatoes. Each of these push pull methods involved ultraviolet reflective mulch and foliar applications of kaolin clay as the push with Bidens alba c ompanion plants acting as the pull in tomatoes and Helianthus annuus as the pull in bell peppers.

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32 CHAPTER 2 EVALUATION OF A PUSH PULL STRATEGY FOR THE MANAGEMENT OF FRANKLINIELLA BISPINOSA (THYSANOP TERA: THRIPIDAE) IN BELL PEPPERS Introduction The inv asive western flower thrips ( Frankliniella occidentalis Pergande) and the native F. bispinosa (Morgan) are pests of numerous crops in Florida, including bell pepper ( Capsicum annuum L). Attempts to control these pests with applications of broad spectrum in secticides were unsuccessful, in part because these insecticides suppress populations of the important natural predator of thrips Orius insidiosus (Say) (Funderburk et al. 2000, Frantz and Mellinger 2009). Additionally, F. occidentalis developed resistance to insecticides from numerous chemical classes with different modes of action (Gao et al. 2012). Both F. bispinosa and F. occidentalis are competent vectors of Tomato spotted wilt virus the type species of an important group of plant viruses in the genus Tospovirus (Avila et al. 2006). Demirozer et al. (2012) reviewed integrated pest management programs for thrips in fruiting vegetables that are effective, economical, and ecologically sound. The components included the following: define pest status (econo mic thresholds), increase biotic resistance (natural enemies and competition), integrate preventive and therapeutic tactics (scouting, ultraviolet (UV) reflective mulch technologies, biological control, compatible insecticides, companion plants, and fertil ity), and vertically integrate the programs with other pests. These programs have been widely implemented in Florida, and they have significantly improved management of Frankliniella thrips and thrips transmitted tospoviruses. Natural populations of O. in sidiosus rapidly invade pepper fields in Florida in numbers sufficient to suppress thrips populations (Funderburk et al. 2000,

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33 Ramachandran et al. 2001). This predator successfully preys on all the common species of flower thrips and their larvae (Baez et al. 2004 Reitz et al. 2006). Funderburk et al. (2000) reported that its ability to suppress populations of Frankliniella species exceeded the suppressive effects of weekly applications of insecticides. Thrips locate their host pl ants using visual cues in the ultraviolet light range (Terry 1997). The light reflected by ultraviolet reflective mulches disrupts this natural mechanism thereby reducing the numbers of thrips landing on plants (Stavisky et al. 2002, Reitz et al. 2003, Momol et al.2004, Riley and P appu 2004). In addition to disrupting host finding by thrips and other insects, ultraviolet reflective mulch decreases incidence of insec t vectored diseases, including T omato spotted wilt, and increases yields (Greenough et al. 1990, Stavisky et al. 2002, Greer and Dole 2003, Reitz et al. 2003, Hutton and Handley 2007, Diaz Perez 2010, Riley et al. 2012). Reitz et al. (2003) reported that populations of O. insidiosus were reduced by ultraviolet reflective mulches, thereby resulting in effects on predator pr ey dynamics (Reitz et al. 2003). Kaolin, an aluminosilicate particle film, is an organic method of managing pests on crops (Bar Joseph and Frenkel 1983). This film acts through multiple modes of action to reduce pests and diseases on crops. Modes of action include interfering with feeding behavior and oviposition, increasing mortality, concealing the host plant visually or chemically, reducing survival rate, and lengthening developmental time (Lapointe 2000, Wilson et al. 2004, Barker et al. 2006, Peng et a l. 2010). Applying kaolin effectively decreased populations of psyllids (Daniel et al. 2005, Peng et al. 2010), aphids (Bar Joseph and Frenkel 1983, Marko et al. 2008), thrips (Spiers et al. 2004, Reitz et al. 2008), weevils (Lapointe 2000, Marko et al. 20 08), lepidoptera (Barker et al.

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34 2006), and others (Marko et al. 2008). Incidence of insect vectored disease was lowered on plants coated in kaolin (Creamer et al. 2005, Reitz et al. 2008). Some studies indicated that kaolin applications increased yield (S piers et al. 2004, Reitz et al. 2008, Cantore et al. 2009) while other studies indicated decreased yield or no difference (Wilson et al. 2004, Creamer et al. 2005, Kahn et al. 2008, Larentzaki et al. 2008). In tomatoes kaolin reduced fruit temperature and sunburn damage, and increased lycopene content and red coloration of the fruit (Cantore et al. 2009). On chile peppers kaolin reduced water stress, increased levels of chlorophyll, and increased light reflectance of leaves (Creamer et al. 2005). Different species of thrips or their damage were reduced on crops by applying kaolin. Application of kaolin reduced populations of F. tritici on tomatoes (Reitz et al. 2008), thrips foliar injury on peanuts (Wilson et al. 2004), populations of Frankliniella spp on blueberries (Spiers et al. 2004), and populations of T. tabaci on onion (Larentzaki et al. 2008). Porcel et al. (2011) reported that populations of most natural enemies were not affected on plan ts treated by kaolin, although Chrysoperla carnea preferred t hem for oviposition. Bengochea et al. (2013) reported that application of kaolin increased the mortality of Anthocoris nemoralis a predator of olive psyllids and thrips. Plant species diversification of agricultural landscapes is a method of habitat manipu lation that allows for a number of ecosystem services, including biological control (Kogan and Lattin 1993). Plants provide resources for natural enemies including food, alternative prey or hosts, and shelter from adverse conditions (Landis et al. 2000). C ertain plant host species or cultivars can be deliberately planted to conserve and

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35 augment populations of natural enemies. A diverse diet of pollen and thrips prey offered O. insidiosus decrease d nymphal development time, and produced larger females than a diet of thrips alone (Wong and Frank 2013). Numerous studies have shown that companion plant species that are hosts for Orius spp. resulted in reduced numbers of Frankliniella spp. thrips in th e main crop. Kasina et al. (2006) and Lopez & Shepard (2007) reported that Tagetes erecta L., Daucus carota L., Coriandrum sativum L., Brassica oleracea L., Capsicum annuum L., Zea mays L., and Tanacetum parthenium (L.) Sch. Bip. attracted enough O. insidi osus to reduce F. occidentalis populations on Phaseolus vulgaris L. and medicinal plant species. Nyasani et al. (2012) reported that intercrops of Solanum tuberosum L. and Helianthus annuus L. reduced populations of F. occidentalis and increased population s of Orius spp. in P. vulgaris In Florida Bidens alba sunflowers ( Helianthus annuus ), Wedelia trilobata and two species of clover are hosts for minute pirate bug and other natural enemies (Bottenberg et al., 1999, Legaspi and Baez 2008), and plantings n ear crops of fruiting vegetables increase biological control of thrips from O. insidiosus (Frantz and Mellinger 2009). The above mentioned studies supposed that predation from O. insidiosus was the mechanism responsible, at least in part, for the reduced n umbers of thrips in the main crop. Companion plants can reduce insect pests on the crop by serving as a sink for the pests or by serving as habitat for natural enemies that feed on the pest either in the companion plant or on the crop. Plants that serve a s hosts for natural enemies and traps for crop pests are important components of push pull strategies (Cook et al. 2007). In such a system, the herbivore is pushed away from the crop and pulled toward

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36 a companion plant where they are removed by the natural enemy. Behavior of the natural enemy can be manipulated using appropriate stimuli to increase biological control of the herbivore either in the companion plant, the crop, or both the companion plant and the crop. The purpose of this research was to evalua te a push pull system for managing flower thrips on peppers. Push components under evaluation were UV reflective mulch and foliar applications of kaolin, and the pull component was the companion plant sunflower H. annuus The objectives were to determine t he separate and interactive effects of each component on the abundance and population dynamics of Frankliniella species, O. insidiosus and the yield and quality of pepper. Methods Plot Establishment And M aintenance were conducted in 2011 and 2012 at the Glades Crop Care, Inc., farm located at 18674 131 st Trail, Jupiter, FL 33458. Plots were fertilized with 148, 59, and 148 kg/ha of N, P, and K, respectively, by broadcasting and roto tilling prior to shaping the beds. Six week old pepper seedlings were transplanted in raised beds covered in plastic mulch (Berry Plastics Corp., Evansville, IN 47706) with trickle tube irrigation according to typical commercial practices for Florida. The beds were 20.3 cm in height and 81 .4 cm in width, with 1.52 m row spacing. Liquid fertilizer 8 0 8 was injected through the drip irrigation system as needed to maintain crop growth of peppers. In 2011 the experiment was a completely randomized design with three replications Treatments were sunflower companion plants, UV reflective mulch, UV reflective mulch plus sunflower

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37 companion plants, black mulch plus foliar applications of kaolin, black mulch plus foliar applications of kaolin plus sunflower companion plants. Peppers were transplanted on 16 and 17 February 2011. Kaolin (Surround WP Engelhard Corp., Iselin, NJ 08830) was applied weekly on 9, 11, 18, 25 of March and 1, 15, 20, and 28 of April 2011 at the rate of 7.0 kg/ha with a CO 2 powered backpack sprayer equipped with three nozzles applying 65 g/a Each of the 18 plots consisted of 4 beds by 14.6 m with each bed consisting of two linear rows of peppers with a 30 cm spacing between and within rows for a total of 257 pepper pl cut plot of each treatment. Sunflowers also were planted at both ends of each bed of each plot of each treatment cont aining companion plants. In 2012 the experiment was a split split plot randomized complete block design with three replicates. Whole plot treatments were UV reflective and black mulch, subplot treatments were kaolin and a control of no kaolin, and sub sub plot treatments were sunflower companion plants and a control of no sunflower. Sub sub plot size was 6 beds by 9.1 m with the four inner beds of each sub subplot consisting of two linear rows of pepper with a 30 cm spacing between and within rows for a tot al of 384 pepper plants. Spacing between beds was 1.8 m. Peppers were transplanted into the field on 21 February 2012. The two outer beds of each sub subplot consisted of black mulch subplo ts of treatments with companion plants and thinned after emergence to 364 plants per plot Sunflowers also were planted at both ends of each bed of each plot of each treatment containing

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38 companion plants. Kaolin was applied once per week on 16, 26, 27 of March and 3, 10 of April and 2 May 2012 at the same rate and method as described previously for 2011. Insect S ampling Frankliniella and Orius are anthophilous and highly aggregated in the flowers of pepper plants; consequently, flowers were sampled to est imate density (Hansen et al. 2003). Sampling for insects began within a few days of first flowering. Two samples of ten pepper flowers were randomly collected from the inner four beds of each plot once per week for six weeks in 2011. In 2012 the samples we re collected twice per week for the first two weeks and once per week for the next three weeks. Two random samples of three sunflower inflorescences also were collected from each plot with companion plants on the same dates. Flowers were placed immediately into vials or bags of 70% ethanol. Thrips and other insects were extracted from the flowers in each sample and identified to species, life stage, and g ender under a stereoscope with 40 X magnification. The number of adult O. insidiosus adult O. pumilio a nd nymphal Orius spp. in each sample was determined. Tomato Spotted Wilt Incidence Each pepper plant in each plot was examined weekly for visual symptoms of Tomato spotted wilt virus infection. Leaf samples were taken from any plant showing visual symptom s, and they were tested for the presence of Tomato spotted wilt virus using ImmunoStrips (Agdia, Elkhart, IN 46514).

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39 Yield Peppers were harvested on 03 and 17 May in 2011 and on 27 April and 10 May in 2012. Peppers of marketable size were picked from 6 .1 m lengths of row located on the two center rows of each plot. Harvested fruits were counted, weighed, and graded for marketability according to USDA standards (USDA 2007). Data Analysis The number of thrips larvae per adult F. bispinosa was determined on each sample date for each treatment and plant. Ratios of < 1, 1, and > 1 were considered indicative of a declining, stable, and increasing population, respectively (Northfield et al. 2008). The ratio of total thrips (adults and larvae) per O. insidiosu s was determined for each treatment and plant on each sample date. The predator is capable of suppressing a thrips population at a ratio of 1 predator per 217 thrips (Sabelis and van Rijn 1997). Differences between treatments in numbers of male and female F. bispinosa thrips larvae, and O. insidiosus and pumilio adults and Orius species nymphs on tomatoes and sunflowers separately were analyzed using analysis of variance for a completely randomized design in 2011 and for a randomized complete block design for a split split plot treatment arrangement in 2012 (PROC GLIMMIX, SAS Institute 2008). When the main effect of treatment was significant (P < 0.05) in 2011, the sums of squares were further partitioned into orthogonal contrasts. Type 3 tests of the main and interactive effects and the orthogonal contrasts comparing treatments were made using the remaining residual in the ANOVA model. Response variables were transformed as needed and each analysis performed using a specified distribution for best fit. In 2011, data for the F.bispinosa females, thrips

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40 larvae and adult O. insidiosus were analyzed using the original counts on a negative binomial distribution, data for the adult male F.bispinosa and for adult O. pumilio were transformed using square root (x + 0.5) on a normal distribution, and data for Orius nymphs were analyzed using the original counts on a poisson distribution. In 2012, the Poisson distribution was used to analyze the original counts for F.bispinosa males and females and for Orius nymphs. Or iginal counts of thrips larvae were fitted to the negative binomial distribution for analysis. The counts for O. pumilio and O. insidiosus were log 10 transformed (x + 0.1) to normalize these variables and analyzed on a normal distribution. Differences in yield between treatments were analyzed with ANOVA using the GLIMMIX procedure. The distributions for each yield variable were normal, so the analyses were conducted on the original data. The distributions of insects on sunflowers were normal, and these ana lyses were conducted on the original data. Results The predominant thrips species in the sunflower and pepper flowers was F. bispinosa Other species accounted for only 0.4 and 0.2% of the adult thrips in the pepper flowers in 2011 and 2012, respectively. Other species in the samples were F. occidentalis F. schultzei and F. fusca Overall the mean number ( + SEM) of adult and larval F. bispinosa in pepper was greater in 2012 (83.6 5.9 per 10 flowers) than in 2011 (46.7 4.7 per 10 flowers). Seasonal tren ds in population abundance of F. bispinosa during 2011 and 2012 in plots with and without sunflower companion plants are shown in Figures 2 1 and 2 2, respectively. The numbers of F. bispinosa male and female adults were greatest during the first or second week of sampling each year, and the larvae were greatest during the second week of sampling. The adults and larvae

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41 declined on later sample dates until reaching very low numbers during the fourth week of sampling each year. The mean ratios of thrips larv ae to adult F. bispinosa on peppers and sunflowers for each different treatment in 2011 are shown in Table 2 1. Thrips populations were increasing at the beginning of the season in all treatments on sunflowers, followed by declining populations towards the end of the season. Thrips populations were always decreasing on peppers over black mulch with or without sunflower companion plants, but were increasing in the reflective mulch and kaolin conditions until the end of the season at which time the population s were decreasing. The mean ratios of thrips larvae to F. bispinosa adults on peppers and sunflowers in each condition in the 2012 experiment are shown in Table 2 2. Thrips populations were very rarely increasing during 2012, but were rather decreasing in most conditions for most of the season in 2012. Two species of Orius were collected. The mean number ( + SEM) over all samples in pepper in 2011 and 2012 was greater for O. insidiosus (0.76 0.07 and 2.67 + 0.18 per ten pepper flowers, respectively) than fo r O. pumilio (0.41 0.05 and 0.39 + 0.05 per ten pepper flowers, respectively). The numbers of Orius species adults were small (approximately 1 per 100 flowers) during the first week of sampling in 2011 and 2012 (Figs. 2 3 and 2 4, respectively). Nymphs o f Orius were first detected in pepper during the second week of flowering. The numbers of adults and nymphs increased and were greatest during the fifth through seventh weeks of flowering. The mean ratios of thrips to Orius in peppers and sunflowers in eac h treatment are shown for 2011 in Table 2 3 and for 2012 in Table 2 4. In 2011 prey to predator

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42 ratios were always at the level appropriate for suppression with the exception of the black mulch treatment in peppers on the first sample date. In 2012 the pre y to predator ratios were always at the level sufficient for suppression with the exception of the ratios in the pepper flowers of three conditions on March 29. There were six treatments in 2011. These included black mulch with and without companion plants black mulch and kaolin clay with and without companion plants, and ultraviolet reflective mulch with and without companion plants. The results of the interaction of compani on plants and the other treatments on numbers of adult and immature F. bispinosa species in pepper flowers for individual sample dates in 2011 are shown in Table 2 5. Companion plants resulted in a significant increase in the number of adult male, adult fe male, and larval F. bispinosa in the pepper flowers during the first week of sampling on 26 Mar in 2011 (Fig. 2 1). The effect of companion plant was not significant on later 2011 sample dates, except for adult males during the fifth week of sampling on 29 Apr. The other treatments significantly affected the number of female, male, and larval F. bispinosa in 2011 (Table 2 5). During the first week of sampling on 31 Mar, the number of adult males ( F =38.55; df=1,12; P <0.0001) and females ( F =5.91; df=1,12; P = 0.0317) in the treatments o f black mulch plus kaolin and ultraviolet reflective mulch were significantly less than in the treatment of black mulch alone (Fig. 2 5). There were no significant differences between treatments of black mulch, black mulch plus kaolin, and ultraviolet reflective mulch in the numbers of adult females on later 2011 sample dates. There were no significant differences in 2011 between treatments of black mulch,

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43 black mulch plus kaolin, and ultraviolet reflective mulch in the numbers o f adult males on 6 Apr, 22 Apr, and 6 May or in the numbers of larvae on 31 Mar, 6 Apr, 22 Apr, 29 Apr, and 6 May. Numbers of adult males of F. bisinosa were greater in treatments o f black mulch plus kaolin and ultraviolet reflective mulch than in the trea tment of black mulch alone on 14 ( F =12.35; df=1,2; P =0.0043) and 29 Apr ( F =12.47; df=1,12; P =0.0041) in 2011. Numbers of larval F. bis p inosa were greater in treatments o f black mulch plus kaolin and ultraviolet reflective mulch than in the treatment of bl ack mulch alone on 14 Apr ( F =41.20; df=1,12; P <0.0001) in 2011. There were no significant interactive effects of companion plants with these other treatments on the number of F. bispinosa in 2011 (Table 2 5). There were eight treatments in 2012. These wer e a factorial of the two mulches, companion plants/no companion plants, and kaolin/no kaolin. The results of the plants, and kaolin on numbers of adult and larval F. bispinos a species in pepper flowers for individual sample dates in 2012 are shown in Table 2 6. As in 2011, companion plants resulted in significant increases in the number of adult male, adult female, and larval F. bispinosa in the pepper flowers during the first week of sampling on 26 and 29 Mar in 2012 (Fig. 2 2 ). Unlike 2011, companion plants resulted in significant decreases during the next two weeks of sampling in the number of adult females in the pepper flowers. Further, there were significant decreases in the number of adult males in the pepper flowers in the companion plant treatments during the second week of sampling. The effect of companion plant was not significant for adult females on 19 and 26 Apr; for adult males on 5, 12, and 19 Apr; and for larvae on 2, 5, 12, 19, and 26 Apr.

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44 There were no significant effects of mulch on the numbers of adult female, adult male, and larval F. bispinosa on any sample date in 2012 (Fig. 2 6, Table 2 6). The numbers of adult female and larval F. bispinosa were signifi cantly reduced by kaolin application on the first three sample dates in 2012 while the numbers of adult male F. bispinosa were significantly reduced by the application of kaolin on the first four sample dates in 2012 (Fig. 2 7, Table 2 6). Conversely, the numbers of adult females were significantly increased by the application of kaolin on 12, 19, and 26 Apr 2012 and the numbers of adult males were significantly increased on 19 Apr. There were no significant differences for adult females on 5 Apr, adult mal es on 12 and 26 Apr, and larvae on 5, 12, 19, and 26 Apr in 2012. The interactive effect of companion plant*kaolin was not significant for adult F. bispinosa on any sample date except 2 Apr when it was significant for males. This interaction was due to a l arger increase in thrips numbers on pepper plants when kaolin was not used in the peppers that were planted without sunflowers compared to the difference in peppers planted with sunflowers. There were significant interactions of companion plant*mulch for l arvae in 2012 on 2 and 5 Apr. This interaction indicated a larger effect of mulch on thrips larvae numbers in peppers planted alone than in peppers planted with sunflowers. More thrips larvae were found on plants in the reflective mulch and peppers planted alone condition. The interactive effect of mulch*kaolin was not significant for adults or larval thrips on any sample date in 2012. The interactive effect of companion plant*mulch*kaolin was not significant for adult or larval F. bispinosa except for fema les on 26 Mar. This interaction indicates that on the first date of the season sunflowers decrease the thrips numbers on pepper plants

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45 in the two kaolin conditions, but increase the numbers of thrips on companion plants when no kaolin is used and when blac k mulch is used in place of reflective mulch. Effects of treatments on Orius in pepper flowers. The mean numbers ( + SEM) of adult O. insidiosus adult O. pumilio and Orius nymphs in treatments of pepper with and without sunflower companion plants in 2011 a nd 2012 are shown in Figures 2 3 and 2 4, respectively. There was little effect of the companion plants on the numbers of Orius in the pepper flowers. There were no significant effects on the numbers of adult O. pumilio in 2011 (Table 2 5). The effects on numbers of adult O. insidiosus and Orius nymphs were significant on only one sample date in 2011. There were no significant effects of companion plants in the numbers of O. pumilio adults, O. insidiosus adults, or Orius nymphs on any sample date in 2012 (T able 2 6). The mean numbers ( + SEM) of adult O. insidiosus adult O pumilio and Orius nymphs in the black mulch, black mulch plus kaolin, and ultraviolet reflective mulch treatments of pepp er in 2011 are shown in Figure 2 8 The numbers of adult O. insidi osus were significantly less in pepper flowers of the ultraviolet reflective mulch and black mulch plus kaolin treatments compared to the black mulch treatment on the 22 Apr sample date in 2011 ( F =12.34; df=1,12; P =0.0043) (Table 2 6 ). The numbers of adul t O. pumilio in pepper flowers of the ultraviolet reflective mulch and black mulch plus kaolin treatments were significantly less compared to the black mulch treatment on 6 ( F= 8.49; df=1,12; P =0.013) and 22 Apr ( F =9.53; df=1,12; P =0.0094) in 2011 (Table 2 5). There were no other significant differences between mulch and kaolin treatments in the numbers of adult O. insidiosus in 2011. The numbers of adult O. pumilio in pepper flowers of the ultraviolet reflective mulch treatment were significantly greater than the

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46 black mulch and black mulch plus kaolin treatments on the 6 May sample date in 2011 ( F =9.59; df=1,12; P =0.0093). The numbers of Orius nymphs in the pepper flowers of the ultraviolet reflective mulch treatment were significantly less than black mul ch on the 14 Apr sample date in 2011 ( F =8.83; df=1,12; P =0.0117). They were significantly greater in ultraviolet reflective treatment than the black mulch and black mulch plus kaolin treatments on the 29 Apr sample date in 2011 ( F =11.91; df=1, 12; P =0.0048 ). The mean numbers ( + SEM) of adult O. insidiosus adult O. pumilio and Orius nymphs in the black mulch and ultraviolet reflective mulch treatments of pepp er in 2012 are shown in Figure 2 9 There were no significant effects of mulch treatment on the numb ers of adult O. pumilio or the numbers of Orius nymphs in 2012 (Table 2 6). The effect of mulch was significant for adult O. insidiosus only on the 12 Apr date in 2012, in which the numbers w ere significantly less in the ultraviolet reflective versus the b lack mulch treatment. The effects of kaolin clay on Orius in 2012 were more consistent than those of mulch (Fig. 2 10). Adults of both species and Orius nymphs were more abundant on plants that were not coated in kaolin clay than on plants that had been s prayed with kaolin clay. This effect was significant on the third collection date for adults of both species and at the end of the season for nymphs. The ANOVA results for the effects of the treatments on the numbers of thrips and Orius found on sunflowers are shown in Table 2 7. Ultraviolet r eflective mulch under peppers significantly increased numbers of thrips larvae found on sunflowers in those plots compared to black mulch or kaolin treatments on Mar 31 2011 (Fig. 2 11) as revealed by orthogonal contras ts ( F =199.20; df=1,2; P =0.0050). On 22 Apr 2011 thrips

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47 larvae numbers were greatest in sunflowers in pepper plots planted with black mulch when compared to ultraviolet reflective mul ch and kaolin treatments (Fig. 2 11 ) as revealed by orthogonal contrasts ( F =648; df=1,2; P =0.0015). Black mulch also significantly increased the numbers of adult male F. bispinosa found on sunflowers compared to kaolin and ultraviolet reflective mulch treatments on 29 April 2011 ( F =204.45; df=1,2; P =0.0049). Treatments did not h ave any other significant effects in 2011. The ANOVA results for the effects of kaolin and mulch on insect numbers found in sunflowers in the 2012 experiment are shown in Table 2 8. There were no significant treatment or interaction effects on the numbers of female F. bispinosa Numbers of male F. bispinosa were significantly reduced by kaolin and also by ultraviolet reflective mulch (Table 2 8, Fig. 2 12). There was a significant interaction effect of mulch and kaolin on the numbers of thrips larvae on 26 April, however the difference was too small to be practically important (Table 2 8, Fig. 2 12). Applications of kaolin significantly reduced numbers of adult O. insidiosus on 26 March (Table 2 8, Fig. 2 12). A significant interaction effect of kaolin and m ulch on O. pumilio was found on two dates (Table 2 8). On 26 March the interaction was such that kaolin decreased the population of O. pumilio on sunflowers in the ultraviolet reflective mulch condition, but increased their numbers in the black mulch condi tion (Fig. 2 12). On the April 12 kaolin did not affect populations on sunflowers in the ultraviolet reflective mulch condition but decreased populations in the black mulch condition (Fig. 2 12). There were no significant effects on Orius spp. nymph popula tions (Table 2 8).

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48 The mean number and weights ( + SEM) of the peppers harvested by each size as well as the results of the ANOVAs of the effects on yield in 2011 are shown for the first harvest on 3 May, the second harvest on 17 May, and the total both harv ests in Table 2 9. There were very few extra large fruits in 2011 and these were combined with the large fruits for analysis. Unmarketable fruits in 2011 were not due to thrips damage, but rather were the result of damage from Heteropterans. Companion plan ts had a significant effect on the number and weight of medium marketable fruits harvested on the second harvest date, which were also the total medium fruits harvested as none were harvested on the first date. Highest yield in pounds and number of medium marketable fruits was obtained from plots grown without sunflowers. Sunflowers also significantly decreased the number of marketable large and extra large peppers harvested on the second date. Mulch and kaolin treatments did not affect medium peppers in 20 11 but significantly affected the weight of large and extra large peppers harvested on the first date. Ultraviolet r eflective mulch significantly increased yield of large and extra large tomatoes on the first date compared to black mulch and kaolin ( F =11.9 5; df=1 ,12; P =0.0047). Treatments of ultraviolet reflective mulch and kaolin both increased the yield of large and extra large peppers significantly compared to black mulch for the season total by weight ( F =9.62; df=1,12; P =0.0092) and number ( F =6.92; df=1 ,12; P =0.0275). The mean number and weights ( + SEM) of medium, large, and extra large fruits on the 27 Apr harvest, the 10 May harvest, and the total of both harvests in the 2012 experiment are shown in Table 2 10. There were few unmarketable fruit in 2012, so the data were not included. Harvested fruits were mostly extra large on the first harvest

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49 date, while medium, large, and extra large fruits were harvested on the second harvest date. There were no significant effects of companion plant or mulch on the number and weights of fruits of any size on the first or second harvest dates. Application of kaolin significantly increased the number and weights of extra large fruits on the first and second harvests. Application of kaolin significantly increased the we ights of large fruits on the second harvest date. Only the number and weights of extra large fruits were significantly increased by application of kaolin when the number and weights of fruit were combined over both harvests. The interactive effect of mulch *kaolin on the number and weights of extra large fruits was significant for the second harvest and for the total of both harvests. This was due to a greater number and weight of fruits by application of kaolin o n black compared to ultraviolet reflective mu lch. Discussion In both years of the experiments the native F. bispinosa was the only species of thrips found in considerable numbers. In this region of Florida, when broad spectrum insecticides are not used as they were not in this experiment, F. occident alis is outcompeted by this native species and consumed by preferentially by Orius spp. (Funderburk et al. 2000, Reitz et al. 2006, Frantz and Mellinger 2009, Funderburk 2009). Due to the lack of this capable vector of Tomato spotted wilt, and due also to the lack of competency of F. bispinosa to vector the disease in the field (Avila et al. 2006), the infection was not present in the fields in either year. The population abundance of F. bispinosa followed a very distinct pattern in both years. The adults a re present in the flowers at the end of March and beginning of April, followed by a peak in larval populations a weak later. Once the predator Orius begins to arrive in the fields, even in

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50 numbers as small as one or two adults per 10 pepper flowers, the th rips populations immediately decrease at an accelerated pace reaching near extinction only one week after Orius numbers begin to increase. This clear relationship between the predator and its prey illustrates how effective this natural control is when pest icides are excluded from a field (Funderburk et al. 2000, Ramachandran et al. 2001, Frantz and Mellinger 2009). In 2011 the thrips populations were always decreasing on peppers in the black mulch condition. This indicates that either the plants were not s uitable for reproduction due to some antibiotic or antixenotic factor, or that the predators were able to control thrips populations on these plants. Thrips larvae to adult ratios were higher on sunflowers than on peppers which could indicate a reproductiv e host preference. Predation is also a viable explanation. Orius numbers were higher in the black mulch condition than in the other two mulch conditions due to the repellency of the kaolin clay and ultraviolet reflective mulch. In 2012 a similar pattern wa s observed with thrips populations never increasing in the black mulch condition, but with a few increasing populations in the kaolin clay and ultraviolet reflective mulch conditions. Again, in 2012 Orius numbers were higher on black mulch than reflective mulch and higher in plots without kaolin than in those where kaolin was used. This evidence strongly supports the explanation of predation as the force contributing to decreasing populations of thrips. Prey to predator ratios were always high enough for s uppression of thrips populations on peppers in 2011 and were only below this threshold in the black mulch and ultraviolet reflective mulch conditions without kaolin in 2012 for three sample points. These prey to predator ratios demonstrate the superior abi lity of native Orius predators to be present in pepper fields in South Florida in high enough numbers to suppress

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51 thrips when pesticides are not used. In 2012 the addition of kaolin further reduced these ratios. Despite also reducing predator numbers on pe pper plants, kaolin may also reduce thrips numbers enough to contribute to thrips suppression rather than impede it. In 2011, though not always significant, thrips followed a similar distribution pattern across the different mulch conditions to those found in a previous study (Reitz et al. 2003). As in that study, higher numbers of thrips were present on the peppers growing over black mulch early in the season followed by a reversal later in the season when numbers were higher on ultraviolet reflective mulc h. The distribution of thrips larvae in our study and the study b y Reitz et al. (2003) were similar with higher numbers of larvae found in plots with ultraviolet reflective mulch. One possible explanation for this response, presented by Reitz et al. (2003) and with which these results are in agreement, is an effect of the arrestment and repellant qualities of the ultraviolet reflective mulch. Although most thrips are repelled by the reflectance, the few that do land are arrested and will oviposit on the pla nts. Those eggs will have a higher survival rate than those on black mulch due to protection from natural enemies that are repelled by the mulch (Reitz et al. 2003). This explanation is relevant as Orius were repelled by ultraviolet reflective mulch in the current study and the previous study (Reitz et al. 2003). Thrips larvae are more vulnerable to predation by Orius than thrips adults (Baez et al. 2004), which is why this effect is apparent for the larvae but not the adults. This also explains why adult n umbers are higher or the same on ultraviolet reflective mulch later in the season. Another potential mechanism for the higher number of larvae on ultraviolet reflective mulch is the physiology of the plants grown over the different mulches.

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52 Females may ov iposit more on plants grown over ultraviolet reflective mulch and/or larvae may have higher survival rates due to the physical condition of the plants. The ultraviolet reflective mulch modifies temperatures and humidity of the soil and plant canopy (Hutton and Handley 2007), and these different conditions may be beneficial for larvae and eggs. Additionally, by the end of the season plants have grown over the mulch obscuring its reflectance. In 2012 the distribution of thrips adults across the different mulc hes was different from that observed in 2011 and in the Reitz et al. (2003) study. In this case adult thrips were higher on black mulch (not significant) for the entire collection period. This difference may have occurred due to the higher abundance of O. pumilio in ultraviolet reflective mulch towards the end of this period when thrips adults would normally have been higher on ultraviolet reflective mulch. Thrips larvae were higher on ultraviolet reflective mulch in 2012 as they were in 2011, though the di ffe rence was not as great as in 2011 and this can again be attributed to predation by higher numbers of O. pumilio in ultraviolet reflective mulch plots which could compensate for the lower number of O. insidiosus The use of kaolin clay resulted in lower populations of thrips on peppers at the beginning of both seasons and was stronger than any other effect. Thrips numbers were higher on kaolin clay, however, in the middle of the season in 2011 and the end of the season in 2012. These results are contrary to previous reports of the effects of kaolin clay on thrips, which did not find any effect of kaolin clay on thrips populations and concluded that kaolin clay works by interfering with feeding behavior and disease transmission (Wilson et al. 2004, Reitz et al. 2008). The lower number of thrips in plots

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53 that received applications of kaolin clay in this study suggests that the clay does indeed repel F. bispinosa although the mechanism is unknown. A few mechanisms have been found in previous studies to cause this reduction in thrips populations, including reflective properties, reduced oviposition, and increased mortality (Larentzaki et al. 2008). Studies with other insect species suggest additional mechanisms which may also be valid in this context. Some of t hese other mechanisms include reduced ability to perceive the plant through mechanoreception (Peng et al. 2010), vision (Bar Joseph and Frenkel 1983), and olfaction (Barker et al. 2006). A combination of mechanisms is likely responsible for the drastic red uction in thrips populations on plants sprayed with kaolin clay. Further laboratory experiments will need to be conducted to determine any physiological effects the clay may have on F. bispinosa The later season reversal of this effect on thrips is likel y due to the lower numbers of Orius on these plants, as was the case for the ultraviolet reflective mulch. Fewer numbers of predators on these plants allowed thrips to avoid predation. This may have been a result of more thrips surviving on these plants an d/or more adults immigrating to these plants from the control plants to avoid predation. Females of F. tritici and F. occidentalis will disperse from flowers in the presence of O. insidiosus (Baez et al. 2004). This suggests that thrips attempt to flee fro m predators and may flee to other plots with fewer predators. Additionally, the lower number of thrips found in plots without kaolin clay at the end of the season may have been due not to fewer thrips on the plants, but fewer in the flowers. More thrips ma y have fled the flowers to seek refuge on the leaves, away from predators resulting in fewer thrips in those samples of flowers.

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54 Thrips numbers were higher on peppers planted with sunflower companion plants than on those planted alone on the first collect ion date, and this was followed by a reversal in this pattern for adults in 2012 and adult females in 2011. The initial higher numbers of thrips may be due to more thrips being attracted to those fields with sunflowers. After the first date, populations of Orius began to increase in all plots and were higher in plots with sunflowers. These more abundant predators reduced thrips in these plots compared to plots without sunflowers. Some of this later number dilution may also have resulted from thrips being at tracted away from the peppers and to the sunflowers in the plots with sunflowers, which has been suggested (Legaspi and Baez 2008). Future experiments involving the exclusion of predators will help to uncover the mechanism for this and the other effects. I n 2011 there were no interaction effects on thrips distributions, indicating that sunflowers had the same effect on thrips with each mulch and kaolin treatment. In 2012, there were a few significant interactions on only a few dates, which renders the prac tical significance of these results questionable. There was a significant interaction effect of companion plant and mulch type on female thrips numbers on one date. Sunflowers decreased thrips numbers with both mulches, but resulted in a greater difference on black mulch. The same effect was observed with males, however, this effect was significant for two dates and was inconsistent between the dates. Thrips larvae also experienced significant interaction, although a different interaction. The interaction w as on two dates between companion plants and kaolin. Kaolin clay does not reduce thrips numbers as effectively in plots with sunflowers as it does in plots without sunflowers. This suggests that the sunflowers interfere with the activity of the

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55 kaolin clay in some way, perhaps by shading the pepper plants and interfering with the reflective quality of the clay and providing a source of adult thrips that can move easily between the rows of sunflowers and peppers to oviposit. While not a significant interact ion, kaolin clay decreases thrips larvae on ultraviolet reflective mulch to a greater degree than on black mulch, suggesting a synergistic reduction in thrips numbers when the two are used together. Thrips larvae are more abundant on ultraviolet reflective mulch than on black mulch when kaolin clay is not used, due to protection from Orius However, when kaolin clay is used the larvae likely suffer higher mortality which is stronger than the protection from predation. No other interactions were significant in the experiment. The best combination for reduction in thrips numbers at the beginning of the season is a combination of ultraviolet reflective mulch and kaolin clay with no companion plants. Later in the season companion plantings become effective and k aolin clay increases thrips numbers. Sunflowers may act as a source for thrips at the beginning of the season and later in the season may begin to act as a sink (Legaspi and Baez 2008). To avoid the problem of sunflowers acting as a source for thrips pests they can be planted later in the season so the flowers will bloom just after the pepper flowers and attract the thrips away. Planting sunflowers to bloom later in the season and discontinuing kaolin clay applications once predators have reached high enoug h numbers to suppress thrips will likely increase the efficacy of this method. The two different species of Orius responded differently to different mulches. Higher numbers of O. insidiosus were always found on black mulch, demonstrating an obvious aversio n to ultraviolet reflective mulch. The same was not true for O. pumilio

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56 which was variable throughout the season, on some dates appearing in higher numbers on black mulch and on other dates appearing in higher numbers on ultraviolet reflective mulch. The r eason for this is unclear. On the first two dates the distribution of O. pumilio appears to be tracking the thrips, but after this date no relationship can be seen. This species might also be tracking other species of prey that were not recorded in this st udy. Nymphs of Orius displayed another pattern entirely, initially appearing in higher densities on the black mulch until the end of the season at which point they were significantly more abundant on ultraviolet reflective mulch. Higher numbers of Orius n ymphs on peppers grown on ultraviolet reflective mulch could be the result of a number of factors. The potential explanations fall into a few categories: plant canopy conditions, intraguild predation, and prey availability. Different canopy conditions in p eppers grown on reflective mulch could be conducive to the survival of eggs and nymphs of Orius that were oviposited by the few females to land on these plants. This higher survival rate would then lead to higher numbers on ultraviolet reflective mulch com pared to black mulch. Another possibility is intraguild predation. Other potential predators of thrips, Chrysoperla and to a greater extent Geocoris, also feed on Orius spp. (Rosenheim 2005). Intraguild predation by Geocoris exerts a substantial influence on the survival rate and density of Orius tristicolor in cotton and this Geocoris feeds more successfully on Orius nymphs than the vagile adults (Rosenheim 2005). Both Chrysoperla and Geocoris decrease densities of Orius through intraguild predation (Rose nheim 2005). If Geocoris is repelled by ultraviolet reflective mulch as are thrips and Orius the lower

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57 densities of Geocoris in this treatment would allow higher survival rates and higher densities of Orius specifically nymphs, to occur. Additionally, Or ius nymphs may be higher in these plots due to the higher densities of thrips larvae in these plots allowing more nymphs to feed with lower intraspecific competition. Nymphs were not identified to species and as such a third explanation arises: the nymphs could be nymphs of O. pumilio which was more abundant on ultraviolet reflective mulch towards the end of the season This could have resulted in higher numbers of eggs and therefore nymphs of this species on plants in the ultraviolet reflective mulch plots A combination of these factors is also possible and further experiments involving exclusion of intraguild predators and other species is needed to elucidate the mechanism responsible. Similar to the ultraviolet reflective mulch, kaolin clay resulted in a significant reduction in the abundance of Orius on peppers, consistently for both species and all life stages. This reduction may have resulted in part from the repellant nature of the clay and also in part from direct mortality. No studies have been cond ucted to determine the effects of kaolin clay on Orius spp., but a similar predator from the same family, Anthocoris memoralis suffers increased mortality when it is coated with kaolin clay (Bengochea et al. 2013). Using that information and the informatio n gained from this study it is likely that in addition to being repelled by kaolin clay, Orius spp. suffer direct mortality from kaolin clay applications. Laboratory assays are needed to determine if this is so. This negative effect of kaolin clay on natur al predators of thrips can be alleviated by terminating applications of kaolin clay once Orius begin to appear in fields in high enough numbers for suppression of thrips populations. This will likely not change the benefits received when using kaolin clay as indicated by prev ious studies which

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58 found that later applications were not beneficial and that the kaolin clay is most effective when thrips populations are high (Spiers et al. 2004). Additionally, predaceous heteropterans are able to rebound in fields once kaolin clay treatments are terminated (Marko et al. 2008) and cessation of these treatments can allow Orius to move into those fields and continue suppression of thrips populations. The effect of companion plants on Orius populations was not consisten t and is not conclusive. For the different species and life stages the sunflowers had different effects at different times during each season. These differences were only rarely significant. Legaspi and Baez (2008) also did not find differences in the dens ities of O. insidiosus on peppers in the two conditions, and suggest that sunflowers act as a sink for O insidiosus and thrips, rather than a source. Sunflowers, they propose, may serve better as a trap crop for thrips than as an attractant for O. insidio sus and our results are in agreement. Interaction effects on Orius populations were sporadic and inconsistent and are not considered any further. As ultraviolet reflective mulch repels both thrips and their natural enemies, it must be used cautiously to e nsure that the thrips numbers do not build up on this mulch in the absence of predators. Reitz et al. 2003 reported that Orius are arrested by ultraviolet reflective mulch if they are released onto plants grown on this mulch and may lay eggs before dispers ing. Growers can overcome the problem of natural enemies being repelled by the ultraviolet reflective mulch by releasing adults directly onto these plants early in the season (Reitz et al. 2003). Additionally, the presence of sunflower companion plantings increased the number of Orius adults and nymphs on pepper plants in the ultraviolet reflective mulch plots compared to reflective mulch plots without

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59 sunflowers in both years (data not shown). Planting companion plants with reflective mulch may decrease th e repellency of ultraviolet reflective mulch or allow Orius to move into these pepper fields more easily. Effects of mulch and kaolin on the numbers of thrips on sunflowers in 2011 were few and inconsistent. The practical significance of these effects is d ubious. In 2012 kaolin and reflective mulch separately reduced numbers of male F.bispinosa on sunflowers and kaolin reduced numbers of adult Orius on sunflowers. These effects only occurred for one date each indicating that this effect may not be practical ly significant, however the consistency of the effect increasing insect numbers on sunflowers for both predator and prey indicates a potentially valid effect. More research is needed to elucidate the practical significance. Ultraviolet r eflective mulch inc reased yield of extra large fruits in 2011 and large in 2012, although this increase was only significant for extra large fruits in 2011. Increases in yield when ultraviolet reflective mulch is used have been found previously (Greer and Dole 2003, Reitz et al. 2003, Hutton and Handley 2007, Diaz Perez 2010). This difference in yield may have been more apparent if the experiments had been conducted in the fall as one study found higher yield from ultraviolet reflective mulch in the fall growing season but no differences in the spring growing season (Diaz Perez 2010). Higher yield from ultraviolet reflective mulch is likely due to several factors including reduced pest damage, reduced disease incidence and cooler soil temperatures. However, this difference was only significant for extra large fruits in one year, and if growers are more concerned about medium or large fruits they should consider this before choosing to use this mulch as it may reduce yield of those fruits.

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60 Kaolin clay significantly increased yie ld of extra large fruits in 2012 and non significantly increased yield of peppers in 2011. The significant interaction effect of mulch and kaolin indicates that kaolin increases yield of peppers on black mulch to a greater extent than the yield of ultravio let reflective mulch. When kaolin clay is not used, higher yield is produced by plants grown on reflective mulch, but when kaolin clay was used the black mulch yielded more marketable extra large fruits than the ultraviolet reflective mulch. Considering th ese results, if growers are only using the mulch and not the kaolin clay, reflective mulch is superior for yield. However, if a grower will use mulch and kaolin clay or if a grower does not use plastic mulch at all, applications of kaolin clay will increas e yield substantially. Although the effects of kaolin clay on the yield of various crops are mixed, our results are in agreement with those studies that found an increase in yield when kaolin clay was used (Spiers et al. 2004, Reitz et al. 2008, Cantore et al. 2009). Possible explanations for this increase in yield, in addition to reduced insect damage, include: lower disease incidence (Creamer et al. 2005, Reitz et al. 2008), less water and heat stress (Spiers et al. 2004, Creamer et al. 2005), higher leve ls of chlorophyll in the plants (Creamer et al. 2005), or decreased damage from sunburn (Cantore et al. 2009). Companion plants significantly increased yield of extra large fruits in 2011, but did not have a significant effect on yield in 2012. However, a significant interaction with the other treatments indicates that companion plants increase yield in ultraviolet reflective mulch and kaolin clay conditions, while causing a decrease in yield in the black mulch conditions. It may be that in the black mulch conditions the sunflowers acted as a source for thrips to immigrate to the peppers, resulting in more damage and

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61 lower yield. As this interaction effect was not observed for any other fruit sizes or in 2012 it does not seem to be a consistent effect. In or der to reduce thrips populations, increase populations of natural predators and increase yield, this study provides several effective combinations. A combination of reflective mulch with applications of kaolin clay early in the season and sunflower compani on plants that begin blooming after the peppers may provide the best control of thrips and greatest yield. However, growers with limited space can still receive reductions in thrips numbers without the sunflowers. This study indicates that kaolin clay is a the two. Kaolin clay is also applicable for growers that do not use plastic mulch. The results of the sunflowers as a pull stimulus are not conclusive and a different p lant or timing may need to be tested in future research to increase the efficacy of this program. All components of this method can be used in different combinations in organic as well as in conventional farming systems and are compatible with other method s of pest management for other species of pests.

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62 Table 2 1. The ratio of the total number of larval Frankliniella species to the total number of Frankliniella bispinosa adults in the flowers of peppers planted without sunflowers, peppers planted w ith sunflowers, and sunflowers on each sample date in the experiment conducted in 2011 in Palm Beach County, Florida. Treatment 31 Mar. 6 April 14 Aprill 22 April 29 April 6 May Peppers without sunflowers B a 0.41 0.88 0.64 0.42 0.2 0 B/K 1.35 1.05 1.46 0 0.33 0.05 R 0.98 0.79 1.21 1.5 0.33 0.33 Peppers with sunflowers B 0.43 0.92 0.91 0.05 0.16 0.47 B/K 0.25 1.15 2.22 1.67 0.75 0.08 R 0.7 1.47 1.91 0.05 0 0.33 Sunflowers B 1.66 7.71 1.30 0.11 0.16 1.14 B/K 1.98 3.08 1.73 0.02 0.03 0.01 R 2.50 15.77 0.33 0.04 0.05 0.34 a B indicates plants planted on black mulch, K indicates kaolin clay and R indicates pepper plants planted on reflective mulch

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63 Table 2 2. The ratio of the total number of larval Frankliniella species to the total number of Frankliniella bispinosa adults in the flowers of peppers planted without sunflowers, peppers planted with sunflowers, and sunflowers on each sample date in the experiment conducted in 2012 in Palm Beach County, Florida. Treatment 26 Mar. 29 Mar. 2 April 5 April 12 April 19 April 26 April Peppers without sunflowers B a 0.06 0.1 0.23 0.76 0.18 0.15 0 B/K 0.01 0.16 0.34 0.44 0.3 0.1 1.07 R 0.11 0.19 0.75 1.4 0.6 0 0 R/K 0.04 0.19 0.31 0.54 0.27 0.32 0.24 Peppers with sunflowers B 0.04 0.22 0 .77 0.78 0.19 0.04 0 B/K 0.03 0.16 1.2 1.34 0.48 0.08 0.28 R 0.07 0.38 0.55 0.79 0.56 0 0.13 R/K 0.04 0.2 0.73 0.85 0.53 0.12 0.4 Sunflowers B 0.15 0.99 0.29 0.63 0.55 0.74 0.64 B/K 0.14 1.02 0.83 2.54 0.41 1.48 0.84 R 0.32 0.34 0.5 0.5 0.55 1.13 0 .18 R/K 0.35 0.28 0.33 1.86 1.86 0.4 0.32 a B indicates plants planted on black mulch, K indicates kaolin clay and R indicates pepper plants planted on reflective mulch

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64 Table 2 3. The ratio of the total number of adult and larval Frankliniella species to the total number of Orius insidiosus and O. pumilio adults and nymphs in the flowers of peppers planted without sunflowers, peppers planted with sunflowers, and sunflowers on each sample date in the experiment conducted in 2011 in Palm Beach Co unty, Florida. Treatment F value of treatment effect 31 Mar. 6 Apr 14 Apr 22 Apr 29 Apr 6 May Peppers without sunflowers B a 146.25* 87.38* 8* 0.21* 0.17* 0.27* B/K 152* 65.73* 19.19* 0.26* 0.15* 0.41* R --61.5* 19.75* 0.6* 0.15* 0.19* Peppers wi th sunflowers B 218.67 63.51* 1.95* 0.29* 0.64* 0.7* B/K 110* 88.19* 10.55* 0.49* 0.48* 0.84* R --114.04* 38.46* 0.26* 0.03* 0.13* Sunflowers B 69.55* 42.13* 0.73* 6.47* 9.72* 2.46* B/K 173.67* 51.61* 1.52* 8.16* 8.57* 5.19* R 187.96* 128.17* 6.5 8* 6.75* 6.24* 3.43* a B indicates plants planted on black mulch, K indicates kaolin clay and R indicates pepper plants planted on reflective mulch b --indicates no Orius on that date (undefined) *, indicates the number of Orius was sufficient for supp ression of the thrips population

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65 Table 2 4. The ratio of the total number of adult and larval Frankliniella species to the total number of Orius insidiosus and O. pumilio adults and nymphs in the flowers of peppers planted without sunfl owers, peppers planted with sunflowers, and sunflowers on each sample date in the experiment conducted in 2012 in Palm Beach County, Florida. Treatment 26 Mar. 29 Mar. 2 Apr 5 Apr 12 Apr 19 Apr 26 Apr Peppers without sunflowers B a 68* 154.75* 161.08* 41 .82* 8.63* 0.66* 0.26* B/K 36* 39* --b 61* 29.08* 31.49* 4.45* R --361 125.25* 146.75* 13.61* 0.53* 0.16* R/K ----28* 54.5* 25.1* 23.55* 4.18* Peppers with sunflowers B 169.75* 252.38 103.82* 19.63* 2.79* 0.73* 0.18* B/K 40* 47* 78* 20.92* 23 .33* 29.6* 1.08* R 154* 257.11 159.97* 40.41* 9.63* 0.41* 0.14* R/K --60.5* 66.17* 56.67* 16.89* 10.36* 1.33* Sunflowers B 54.73* 53.23* 10.21* 9.3* 3.69* 2.51* 1.79* B/K 55.36* 52.25* 22.74* 7.85* 4.2* 1.75* 3.62* R 53.26* 42.33* 20.21* 13.55* 4. 19* 2.48* 5.7* R/K 58.23* 40.28* 21.97* 15.31* 3.99* 2.08* 0.59* a B indicates plants planted on black mulch, K indicates kaolin clay and R indicates pepper plants planted on reflective mulch b --indicates no Orius on that date (undefined) *, indicate s the number of Orius was sufficient for suppression of the thrips population

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66 Table 2 5. F values for treatment effects in the ANOVAs conducted for individual 2011 sample dates to determine the effects of companion plants, mulch and kaolin on the numbers of adults and immatures of F. bispinosa and Orius species in the experiment conducted in Palm Beach County, Florida. ANOVA treatment effect d.f. F value 31 Mar. 6 April 14 April 22 April 29 April 6 May F. bispinosa adult females C a 1, 12 16.0 ** 0.2 0.4 2.4 0.6 0.3 T 2, 12 4.0* 2.1 2.7 0 3 3.6 C x T 2, 12 0.1 2.2 0.3 0.3 2.2 0.1 F. bispinosa adult males C 1, 12 9.0** 3.2 0.7 0.5 5.3* 0.3 T 2, 12 23.6*** 3.6 7.6** 0.9 6.4** 1 C x T 2, 12 0.3 3.1 2.4 1.1 2.9 0 F. bispinosa larvae C 1, 12 5.7* 1.5 1.3 0.5 1 n/a T 2, 12 3.3 2.2 20.6*** 0.2 0 n/a C x T 2, 12 0.2 5.3* 2 2.7 2.6 n/a O. insidiosus adult males and females C 1, 12 n/a 1.9 0.5 0.1 4.4 5.5* T 2, 12 n/a 1.4 1.7 6.7** 0.3 1.5 C x T 2, 12 n/a 0.8 0.4 1.9 0.9 1.5 O. pumilio adult males and females C 1, 12 0.2 0.3 0.1 0 0.1 3 T 2, 12 1.8 4.3* 0 4.9* 1.2 4.8* C x T 2, 12 0.2 0.3 0.4 0.9 1.4 4.5* Orius species nymphs C 1, 12 n/a n/a 0.1 0.1 10.4** 0.9 T 2, 12 n/a n/a 4.5* 1.4 6.0** 0.2 C x T 2, 12 n/a n/a 2.6 0.4 0.4 1.4 a C i ndicates companion plant effects, T indicates treatment (mulch type, kaolin clay) effects. *, P < 0.05; **, P < 0.01; ***, P < 0.001

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67 Table 2 6 F values for treatment effects in the ANOV As conducted for individual 2012 sample dates to determine the effects of companion plants, mulch and kaolin on the numbers of adults and immatures of F. bispinosa and Orius species in the experiment conducted in Palm Beach County, Florida. ANOVA treatment effect d.f. F value 26 Mar. 29 Mar. 2 April 5 April 12 Apri l 19 April 26 April F. bispinosa adult females C a 1, 8 16.4** 0.5 14.7** 7.4* 5.4* 3.0 0.2 M 1, 2 0.8 1.5 0.2 0.0 1.1 8.8 0.2 C x M 1, 8 0.8 0.0 17.0** 1.5 0.5 0.9 0.0 K 1, 4 42.1** 67.8*** 62.5*** 0.0 34.7** 83.3*** 9.7* C x K 1, 8 0.0 1.0 9.47* 0.9 3.7 0.1 0.1 M x K 1, 4 0.2 1.3 1.7 2.8 1.3 0.0 0.2 C x M x K 1, 8 5.2* 0.0 3.3 0.0 2.2 0.4 0.5 F. bispinosa adult males C 1, 8 18.7** 12.6** 5.2* 0.9 0.0 2.3 5.6* M 1, 2 1.2 2.0 0.8 0.0 0.0 8.2 1.1 C x M 1, 8 1.0 7.2* 8.6* 0.7 0.1 0.0 0.0 K 1, 4 61 .2** 201.3** 180.2*** 11.5* 0.0 119.2*** 3.1 C x K 1, 8 0.0 5.0 1.0 4.9 0.0 2.3 1.9 M x K 1, 4 0.4 0.0 3.5 0.7 0.7 1.1 0.0 C x M x K 1, 8 4.3 5.0 0.2 1.9 0.2 0.3 0.9 F. bispinosa larvae C 1, 8 9.7** 7.8* 3.7 0.6 0.0 n/a n/a M 1, 2 0.6 0.1 0.1 0.0 1. 8 n/a n/a C x M 1, 8 0.1 0.9 0.0 1.5 0.3 n/a n/a K 1, 4 37.6** 43.8** 20.7** 2.4 6.0 n/a n/a C x K 1, 8 2.1 0.2 7.6* 13.9** 0.3 n/a n/a M x K 1, 4 1.0 3.0 2.5 2.7 6.1 n/a n/a C x M x K 1, 8 0.1 2.6 1.4 1.8 0.4 n/a n/a

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68 Table 2 6 Continued AN OVA treatment effect d.f. F value 26 Mar. 29 Mar. 2 April 5 April 12 April 19 April 26 April 26 April O. insidiosus adult males and females C 1, 8 0.1 0.1 0.6 3.6 0.8 2.8 0.3 M 1, 2 3.6 3.2 0.9 1.1 25.6* 5.6 7.9 C x M 1, 8 0.1 1.4 0.8 6.3* 0.4 0.2 0 .0 K 1, 4 0.1 1.0 20.6** 3.6 7.1 12.1* 1.0 C x K 1, 8 0.1 1.4 0.4 0.2 3.1 2.4 0.9 M x K 1, 4 0.1 3.2 3.3 1.7 8.7* 2.5 0.1 C x M x K 1, 8 0.1 0.1 1.4 2.5 0.1 0.0 2.2 O. pumilio adult males and females C 1, 8 0.4 0.5 0.1 0.1 0.9 0.5 0.6 M 1, 2 0.3 0.2 0.3 0.2 0.7 0.2 2.1 C x M 1, 8 0.4 0.5 0.0 0.4 0.4 9.7* 9.6* K 1, 4 2.5 6.2 15.9* 5.0 4.8 1.5 3.5 C x K 1, 8 0.4 0.5 1.0 0.1 0.1 1.5 0.6 M x K 1, 4 0.3 0.2 0.0 0.2 0.8 1.5 0.0 C x M x K 1, 8 0.4 0.5 0.4 0.3 0.0 1.0 4.0 Orius species nymphs C 1, 8 n /a n/a n/a 1.7 0.9 1.5 4.1 M 1, 2 n/a n/a n/a 0.3 0.0 2.2 7.7 C x M 1, 8 n/a n/a n/a 0.3 2.1 0.0 0.3 K 1, 4 n/a n/a n/a 7.1 7.5* 34.3** 24.4** C x K 1, 8 n/a n/a n/a 0.0 0.2 0.9 1.7 M x K 1, 4 n/a n/a n/a 3.0 0.2 0.1 1.0 C x M x K 1, 8 n/a n/a n/a 0. 8 0.0 0.3 0.7 a C indicates effect of companion plants, M indicates mulch effects, K indicates kaolin clay effects. *, P < 0.05; **, P < 0.01; ***, P < 0.001

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69 Table 2 7. F values for treatment effects in the ANOVAs conducted for individual 2011 s ample dates to determine the effects of mulch and kaolin on the numbers of adults and immatures of F. bispinosa and Orius species on sunflowers in the experiment conducted in Palm Beach County, Florida. Variable d.f. F value of treatment effect 31 Mar. 6 April 14 April 22 April 29 April 6 May 26 Apr F. bispinosa adult females 2,2 7.8 1.8 1.8 2.9 12.5 2.6 0.2 F. bispinosa adult males 2,2 3.4 3.3 1.2 0.7 102.4** 3.8 0.2 F. bispinosa larvae 2,2 101.8** 2.5 0.5 327.0** 0.9 3.0 0.0 O. insidiosus adult mal es and females 2,2 2.6 4.0 0.4 0.6 0.7 0.0 0.1 O. pumilio adult males and females 2,2 0.1 0.3 0.5 3.7 1.6 0.1 0.1 Orius species nymphs 2,2 na 3.8 0.3 0.6 0.9 1.5 0.2 *, P < 0.05; **, P < 0.01; ***, P < 0.001

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70 Table 2 8. F valu conducted for individual 2012 sample dates on the numbers of adults and immatures of F. bispinosa and Orius species on sunflowers in the experiment conducted in Palm Beach County, Florida. A NOVA treatment effect d.f. F value 26 Mar. 29 Mar. 2 April 5 April 12 April 19 April 26 Apr F. bispinosa adult females M a 1, 2 0.4 3.5 0.1 0.0 3.7 0.4 0.4 K 1, 4 2.2 1.1 0.0 1.3 0.3 0.9 0.0 M x K 1, 4 4.9 0.0 3.5 0.1 1.3 2.6 3.4 F. bispinosa adult males M 1, 2 1.8 17.3* 5.1 1.0 0.0 1.5 0.6 K 1, 4 0.9 10.6* 0.0 1.8 0.1 0.3 0.1 M x K 1, 4 1.0 6.6 0.5 0.5 1.1 2.1 2.5 F. bispinosa larvae M 1, 2 0.0 1.1 0.4 0.1 1.0 0.9 1.9 K 1, 4 0.0 0.8 0.5 7.2 0.6 2.8 7.1 M x K 1, 4 0.1 0.7 6.0 0.4 3.3 0.2 10.1* O. insidiosus adult males and females M 1, 2 2.0 1.7 0.0 0.1 0.0 2.9 2.0 K 1, 4 11.4* 0.0 0.5 0.8 0.0 0.1 2.1 M x K 1, 4 1.0 0.4 1.5 0.0 1.9 1.1 3.8 O. pumilio adult males and females M 1, 2 0.0 0.1 0.3 0.0 0.0 1.0 0.3 K 1, 4 0.1 1.6 0.3 1.8 2.7 0. 1 1.2 M x K 1, 4 13.1* 1.6 0.1 24.2** 0.4 0.3 0.5 Orius species nymphs M 1, 2 0.9 0.1 0.6 0.2 0.2 5.6 0.1 K 1, 4 0.4 0.4 3.0 0.4 0.5 0.6 0.1 M x K 1, 4 0.9 0.1 2.2 3.6 1.1 0.3 2.4 a M indicates mulch effects, K indicates kaolin clay effects. *, P < 0 .05; **, P < 0.01

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71 T able 2 9. Mean ( SEM) number and weight per plot of medium, large, and extra large fruits harvested on 3 and 17 May 2011 in the push pull experiment conducted in Palm Beach County, Florida. Treatment Mean number (no.) and weig ht (kgs) per plot (SEM) Medium fruits Large and Extra large fruits Marketable Unmarketable Marketable Unmarketable no. kgs no. kgs no. kgs no. kgs 3 May 11 B a 0 0 0 0 91 8 22 2 24 16 7 5 B/C 0 0 0 0 81 11 21 3 44 7 11 2 B/K 0 0 0 0 97 5 24 1 20 9 5 2 B/K/C 0 0 0 0 95 14 25 4 29 10 7 3 R 0 0 0 0 112 22 28 6 13 4 3 1 R/C 0 0 0 0 122 8 38 2 27 5 8 2 ANOVA F value C (1,12 d.f.) --------0 1.7 3.6 2.8 Other trts (2,12 d.f.) ------3 .3 6.4* 1.2 0.9 C*other trts (2, 12 d.f.) --------0.3 1.7 0.2 0.1 17 May 11 B 70 16 11 2 69 30 13 6 36 4 9 1 0 0 B/C 37 7 6 1 84 13 15 3 11 4 3 1 0 0 B/K 76 27 13 5 70 28 14 6 50 9 12 2 0 0 B/K/C 32 4 5 1 46 9 12 2 27 9 7 2 0 0 R 56 16 9 3 37 13 7 3 39 15 9 3 0 0 R/C 39 0 7 0 96 3 21 0 40 4 11 1 0 0 ANOVA F value C (1,12 d.f.) 6.9* 7.2* 1.2 2.4 5.3* 3.6 ----Other trts (2,12 d.f.) 0.1 0.1 0.5 0.1 2.4 2.7 ----C*other trts (2, 12 d.f.) 0.4 0.8 2.5 2.1 1.5 2.5 ----

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72 Table 2 9. Continued. Treatment Mean number (no.) and weight (kgs) per plot (SEM) Medium fruits Large and Extra large fruits Marketable Unmarketable Marketable Unmarketable no. kgs no. kgs no. kgs no. kgs Total 3 May and 17 May 2011 B 70 16 11 2 69 30 13 6 126 12 31 3 24 16 7 5 B/C 37 7 6 1 84 13 15 3 91 14 23 4 44 7 11 2 B/K 76 27 13 5 70 28 14 6 147 14 35 3 20 9 5 2 B/K/ C 32 4 5 1 46 9 12 2 122 19 32 5 29 10 7 3 R 56 16 9 3 37 13 7 3 151 28 37 7 13 4 3 1 R/C 39 0 7 0 96 3 21 0 162 5 49 2 27 5 8 2 ANOVA F value C (1,12 d.f.) 6.9* 7.2* 1.2 2.4 1.5 0 3.6 2.8 Other trts ( 2,12 d.f.) 0.1 0.1 0.5 0.1 4.0* 7.3** 1.2 0.9 C*other trts (2, 12 d.f.) 0.4 0.8 2.5 2.1 1 3.2 0.2 0.1 a B indicates plants planted on black mulch, C indicates companion plants, K indicates kaolin clay and R plants planted on reflective mulch. b C indic ates companion plant effect, T indicates mulch and kaolin treatment effects. *, P < 0.05; **, P < 0.01; ***, P < 0.001;

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73 Table 2 10. Mean ( SEM) number and weight per plot of medium, large, and extra large fruits harvested on 27 April and 10 May 2012 in the push pull experiment conducted in Palm Beach County, Florida. Treatment Mean number (no.) and weight (kgs) per plot (SEM) Medium fruits Large fruits Extra large fruits no. kgs no. kgs no. kgs 27 Apr 12 B a 0 0 0 0 5 4 1 1 56 16 16 5 B/C 0 0 0 0 4 1 1 0 56 12 15 3 B/K 0 0 0 0 3 2 1 0 74 22 20 6 B/C/K 0 0 0 0 11 3 2 1 88 22 23 6 R 0 0 0 0 12 4 2 1 35 7 8 2 R/C 0 0 0 0 10 1 2 0 40 11 10 2 R/K 0 0 0 0 20 11 4 2 43 10 10 2 R/C/K 0 0 0 0 5 1 1 0 46 13 11 3 ANOVA F value C (1, 8 d.f.) n/a n/a 0.7 0.9 1.3 0.9 Mulch (1, 2 d.f.) n/a n/a 3 2.1 6 8.2 C x Mulch (1, 8 d.f.) n/a n/a 3.9 4 0.1 0 K (1, 4 d.f.) n/a n/a 0.4 0.3 11.2* 9.0* C x K (1, 8 d.f.) n/a n/a 0.1 0 0.4 0.6 Mulch x K (1, 4 d.f.) n/a n/a 0 0.1 3.8 4 Mulch x C x K (1, 8 d.f.) n/a n/a 3.6 3.7 0.7 0.7

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74 Table 2 10. Continued. Treatment Mean number (no.) and weight (kgs) per plot (SEM) Me dium fruits Large fruits Extra large fruits no. kgs no. kgs no. kgs 10 May 12 B 30 10 5 2 47 2 9 0 37 9 10 3 B/C 33 10 5 2 60 12 12 2 35 7 10 2 B/K 42 24 8 5 78 5 16 1 85 9 25 3 B/C/K 41 20 7 4 78 13 17 3 77 10 22 3 R 29 5 4 1 99 26 19 5 49 13 12 3 R/C 38 12 6 2 95 14 19 3 51 6 13 2 R/K 31 5 5 1 110 19 23 5 67 12 17 3 R/C/K 30 12 4 2 104 18 22 4 62 7 17 2 ANOVA F value C 0.2 0.1 0 0.1 0 .3 0.2 Mulch (1, 2 d.f.) 0.1 0.1 3.8 3.3 0.1 0.9 C x Mulch (1, 8 d.f.) 0.1 0.2 0.8 0.5 0.1 0.4 K (1, 4 d.f.) 0.3 0.4 7.1 10.2* 30.1** 34.6** C x K (1, 8 d.f.) 0.5 0.8 0.4 0.4 0.4 0.4 Mulch x K (1, 4 d.f.) 1.1 1.3 1.3 0.9 8.1* 8.3* Mulch x C x K (1, 8 d.f.) 0.1 0 0.1 0 0 0

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75 Table 2 10. Continued. Treatment Mean number (no.) and weight (kgs) per plot (SEM) Medium fruits Large fruits Extra large fruits no. kgs no. kgs no. kgs Season Total 27 April 2012 and 10 May 2012 B 30 10 5 2 52 3 10 1 93 25 26 7 B/C 33 10 5 2 64 12 12 2 91 19 25 5 B/K 42 24 8 5 81 4 17 1 159 31 44 8 B/C/K 41 20 7 4 90 16 19 4 165 32 45 8 R 29 5 4 1 110 29 21 6 84 18 20 5 R/C 38 12 6 2 1 05 14 21 3 92 13 23 3 R/K 31 5 5 1 130 29 27 6 109 15 27 4 R/C/K 30 12 4 2 108 19 22 4 108 20 28 5 ANOVA F value C (1, 8 d.f.) 0.2 0.1 0.1 0 0.1 0 Mulch (1, 2 d.f.) 0.1 0.1 4 3.3 4.1 6.1 C x Mulch (1, 8 d.f.) 0.1 0.2 1 .8 1.3 0 0.2 K (1, 4 d.f.) 0.3 0.4 5.1 7.1 26.4** 27.2** C x K (1, 8 d.f.) 0.5 0.8 0.3 0.3 0 0 Mulch x K (1, 4 d.f.) 1.1 1.3 0.9 0.7 7.8* 7.9* Mulch x C x K (1, 8 d.f.) 0.1 0 0.2 0.2 0.2 0.1 *, P < 0.05; **, P < 0.01; ***, P < 0.001; a B indicates pl ants planted on black mulch, C indicates companion plants, K indicates kaolin clay and R indicates plants planted on reflective mulch.

PAGE 76

76 Figure 2 1. The mean number per 10 pepper flowers ( SEM) of F. bispinosa adult females, adult males, and larvae in plots with and without companion plantings of sunflowers in the experiment conducted in Palm Beach County, Florida in 2011 (data pooled over mulch and kaolin treatments).

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77 Figure 2 2. The mean numbe r per 10 pepper flowers ( SEM) of F. bispinosa adult females, adult males, and larvae in plots with and without applications of kaolin clay in the experiment conducted in Palm Beach County, Florida in 2012 (data pooled over mulch and companion plant treat ments).

PAGE 78

78 Figure 2 3. The mean number per 10 pepper flowers ( SEM) of O. insidiosus adults, O. pumilio adults, and Orius spp. nymphs in plots with and without companion plantings of sunflowers in the experiment conducted in Pa lm Beach County, Florida in 2011 (data pooled over mulch and kaolin treatments).

PAGE 79

79 Figure 2 4. The mean number per 10 pepper flowers ( SEM) of O. insidiosus adults, O. pumilio adults, and Orius spp. nymphs in plots with and wi thout applications of companion plantings of sunflower in the experiment conducted in Palm Beach County, Florida in 2012 (data pooled over mulch and kaolin clay treatments).

PAGE 80

80 Figure 2 5. The mean number per 10 pepper flowers ( SEM) of F. bispinosa adult females, adult males, and larvae in plots with black mulch, black mulch and kaolin clay applications, and reflective mulch in the experiment conducted in Palm Beach County, Florida in 2011 (data pooled over companion plant tre atments).

PAGE 81

81 Figure 2 6. The mean number per 10 pepper flowers ( SEM) of F. bispinosa adult females, adult males, and larvae in plots with black or reflective mulch in the experiment conducted in Palm Beach County, Florida in 2012 (data pooled over companion plant and kaolin clay treatments).

PAGE 82

82 Figure 2 7. The mean number per 10 pepper flowers ( SEM) of F. bispinosa adult females, adult males, and larvae in plots with and without applications of kaolin in the experiment conducted in Palm Beach County, Florida in 2012 (data pooled over mulch and kaolin clay treatments).

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83 Figure 2 8. The mean number per 10 pepper flowers ( SEM) of O. insidiosus adults, O. pumilio adult s, and Orius spp. nymphs in plots with black mulch, black mulch and kaolin clay applications, and reflective mulch in the experiment conducted in Palm Beach County, Florida in 2011 (data pooled over companion plant treatments).

PAGE 84

84 Figure 2 9. The mean number per 10 pepper flowers ( SEM) of O. insidiosus adults, O. pumilio adults, and Orius spp. nymphs in plots with black or reflective mulch in the experiment conducted in Palm Beach County, Florida in 2012 (data pooled over compa nion plant and kaolin clay treatments).

PAGE 85

85 Figure 2 10. The mean number per 10 pepper flowers ( SEM) of O. insidiosus adults, O. pumilio adults, and Orius spp. nymphs in plots with and without applications of kaolin clay in th e experiment conducted in Palm Beach County, Florida in 2012 (data pooled over mulch and companion plant treatments).

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86 Figure 2 11. The mean number per three sunflower inflorescences ( SEM) of F. bispinosa adult females, F. b ispinosa adult males, thrips larvae, O. insidiosus adults, O. pumilio adults, and Orius spp. nymphs in plots with black mulch, reflective mulch, or black mulch with kaolin applications in the experiment conducted in Pal m Beach County, Florida in 2011

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87 Figure 2 12. The mean number per three sunflower inflorescences ( SEM) of F. bispinosa adult females, F. bispinosa adult males, thrips larvae, O. insidiosus adults, O. pumilio adults, and Orius spp. nymphs in plots with black mulch, black mulch and kaolin, reflective mulch and reflective mulch with kaolin in the experiment conducted in Palm Beach County, Florida in 2012.

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88 CHAPTER 3 EVALUATION OF A NOVEL PUSH PULL METHOD FOR THE MANAGEMENT OF THRIPS AND TOSPOVIRUSES IN TOM ATOES IN NORTH FLORIDA Introduction Native to southwestern United States, F. occidentalis is now a common pest thrips found on tomatoes and other c rops in Florida. It became a serious economic problem for growers in 2005 (Frantz and Mellinger 2009). This species of thrips causes crop losses due to direct physical damage produced from the thrips feeding and ovipositing on the flowers resulting in unmarketable fruits (Salguero Navas et al. 1991, Ghidiu et al.2006). Additional crop losses from F. occidentalis result from indirect damage when the thrips vectors Tomato spotted wilt virus to the plants leading to reduced yield and unmarketable fruits. Crop losses from tomato spotted wilt have been estimated to reach a cost of US $1 billion (Goldbach and Peters, 1 994). This thrips is capable of vectoring additional viruses including Impatiens necrotic spot virus Chrysanthemum stem necrosis virus Groundnut ringspot virus and Tomato chlorotic spot virus ( Pappu et al. 2009 Webster et al. 2011 ) In addition to F. occidentalis tomato spotted wilt is vectored by seven other species of thrips ( Pappu et al. 2009 ). Of these sp ecies, F. bispinosa Morgan is a native thrips also found on tomatoes in North Florida, but its ability to transmit the virus in the field is not supported by research findings (Avila et al. 2006, Funderburk et al. 2011). A third species of thrips is common ly found in tomatoes in North Florida, the native F. tritici Fitch. Both of these native species can produce direct physical damage on tomato fruits while feeding and ovipositing on fruits, but they do not vector diseases to the

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89 tomatoes and so are not as serious of a threat to tomato growers. These two species also have the ability to outcompete F. occidentalis if allowed to persist in a field (Paini et al. 2008). Another natural control of F. occidentalis and other thrips species is natural predation by the native predator Orius insidiosus (Say). Where these insects are not eliminated by pesticides, they can effectively suppress thrips populations at very high prey to predator ratios (Funderburk et al. 2000).The minute pirate bugs feed on all three specie s of thrips, but they prey preferentially on thrips larvae and the adults of the F. occidentalis over the adults of the non damaging native thrips species (Baez et al. 2004, Reitz et al. 2006). This aspect of feeding makes the minute pirate bugs a valuable tool for managing F. occidentalis. The native thrips species are smaller and move around more frequently and at a faster pace than F. occidentalis and may be the reason for the preferential fee ding behavior (Baez et al. 2004, Reitz et al. 2006). Approxi mately one adult minute pirate bug for every 180 thrips is sufficient for suppression of the populations of thrips with thrips populations being under complete control at a ratio of about one predator to 40 thrips (Funderburk et al. 2000). Usually, natural populations are not sufficient in tomato to provide control of thrips (Baez et al. 2011), and a lower attack coefficient is achieved by O. insidiosus on tomato (Coll and Ridgway 1995). Calendar applications of broad spectrum insecticides, such as pyrethro ids, have been a popular method for controlling thrips in fields. These applications were initially successful with their effects dwindling and reversing with increased use (Funderburk et al. 2000, Funderburk 2009). These chemicals eliminate the natural pr edators and the native species of thrips which would otherwise prevent F. occidentalis from attaining

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90 damaging levels in the field (Funderburk 2009, Reitz and Funderburk 2012). Applications of insecticides to control adult thrips in blossoms do not prevent the virus transmission in fields (Reitz et al. 2003). Furthermore, the life history and genetic adaptations of F. occidentalis lead to the rapid development of resistant populations (Gao et al. 2012). Resistant populations of F. occidentalis combined with a lack of natural predators and competition create a situation in which damaging thrips populati ons are present in a field and cannot be controlled. The ineffectiveness of pesticides for controlling thrips, as well as increasing consumer demand for organi c produce and the struggle of organic growers to keep pace with demand (Dimitri and Oberholtzer 2009) indicate a need for more sustainable and organic methods of managing pests in food crops. Many techniques are currently in use which can effectively red uce thrips populations and are compatible in conventional and organic production sys tems. These include ultraviolet reflective mulch, companion plantings, and kaolin clay. Moreover, a new pest management system has recently been developed for certain cropp deterrent pest management system involves the use of both repellant and attractive stimuli in crop fields to repel pest insect from the crop while attracting them away from the crop to a non crop plant (Khan et al. 2001). Ultraviolet reflective mulch is an effective pest management tool for numerous insect pests on numerous crops (Greenough et al. 1990, Greer and Dole 2003, Reitz et al. 2003). The mulch reflects ultraviolet light which disrupts the ability of certain insects, including thrips, to find the host plant grown on the mulch (Terry 1997). Ultraviolet reflective mulch repels thrips, significantly reduces incidence of Tomato spotted wilt on

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91 tomatoes, and increases yield when compared to insecticides and contro ls (Greenough et al. 1990, Stavisky et al. 2002, Reitz et al. 2003, Riley and Pappu 2004, Riley et al. 2012). The use of this mulch also results in increased yield when compared to black mulch and insecticides (Reitz et al. 2003). When combined with the ju dicious use of insecticides the mulch leads to even greater control, and combining it with other non chemical methods of pest management may also have a synergistic effect. Kaolin clay is an alternative pesticide which is economical, ecological, and easil y washed off plants (Bar Joseph and Frenkel 1983, Reitz et al. 2008). This aluminosilicate mineral is used on plants both for pest control and to protect plants from sun damage (Cantore et al. 2009). The material reduces numbers of insects on plants throug h various modes of action including repelling light, impeding the ability of insects to grasp the plant surface, deterring feeding and oviposition, impeding development and direct mortality (Bar Joseph and Frenkel 1983, Lapointe 2000, Barker et al. 2006, L arentzaki et al. 2008, Peng et al. 2010). Kaolin clay effectively repels thrips from blueberries, onions, and tomatoes (Spiers et al. 2004, Larentzaki et al. 2008, Reitz et al. 2008). Kaolin clay also reduces pest numbers (Marko et al. 2008), damage caused by pests (Wilson et al. 2004) and disease incidence (Wilson et al. 2004, Creamer et a l. 2005) on crops. Use of this kaolin clay on tomatoes resulted in reduced thrips numbers, reduced incidence of Tomato spotted wilt, and increased yield (Reitz et al. 200 8). The reduction in disease incidence and increased yield from the use of kaolin clay and essential oils was as effective as standard broad spectrum insecticides (Reitz et al. 2008). Its use in pears significantly reduced numbers of Cacopsylla pyri compar ably or slightly better than IPM or organic control (Daniel et al. 2005). Lacewings prefer to oviposit on kaolin

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92 treated surfaces (Porcel et al. 2011). One potential negative effect associated with the use of kaolin clay is possible repellence and mortali ty to natural enemies (Marko et al. 2008, Bengochea et al. 2013). However, once the applications are stopped, the predators that were repelled can rebound (Marko et al. 2008). Although natural populations of minute pirate bugs are too low in tomato fields to provide control of thrips (Baez et al. 2011), there is potential to attract minute pirate bugs into these fields using habitat management strategies such as companion plantings. Minute pirate bugs are known to supplement their diet with plant materials such as pollen and can develop and reproduce on a diet of pollen and nectar alone for up to six months (van den Meiracker and Ramakers 1991). Their survival rate, life span and reproduction rate, and adult female size are higher, and the developmental time is shorter on a diet of thrips and pollen than on a diet of thrips alone (Kiman and Yeargan 1985, Wong and Frank 2013). Minute pirate bugs are also more abundant where pollen is present and will migrate in the absence o f pollen (Malais and Ravensburg 1992 ). Habitat diversification and the presence of flowering weeds successfully increases the numbers of natural enemies and decreases the numbers of pest insects (Showler and Greenburg, 2002; Ghodani et al. 2009, Chaplin Kramer et al. 2011, Amaral et al. 201 3) while also increasing the abundance and richness of pollinators (Chaplin Kramer et al. 2011). The suppression of these pests and the injury they cause using habitat diversification was superior to suppression using insecticides (endosulfan and monocroto phos). The diversification also led to increased yield of cotton (Ghodani et al. 2009). In a study by Lundgren et al. 2009 the addition of plants with suitable oviposition sites and refuges from natural enemies was associated with lower herbivore

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93 densities and higher predator densities on the target plant. The densities of minute pirate bugs in this study were higher on the target plants in polycultures than in monocultures. Minute pirate bug nymphs also experienced higher fitness in diverse fields (Lundgre n et al. 2009). Minute pirate bugs have the ability to rapidly recolonize plots treated with insecticides (Ramachandran et al. 2001) and this ability could be enhanced with the addition of companion plantings in which the minute pirate bugs could take shel ter to avoid insecticides and then later recolonize the sprayed plots. Many plant species offer habitat for important natural enemies of t hrips and other insects (Landis, Wratten and Gurr 2000). Non crop plants have been shown to attract enough enemies to control F. occidentalis populations on green beans and medicinal plants (Kasina et al. 2006, Lopez and Shepard 2007). Intercrops of baby corn, Irish potato and sunflowers with French beans in Kenya reduced populations of F. occidentalis and increased popul ations of Orius spp. compared with a monocrop (Nyasani et al. 2012). Intercrops of dill, coriander and buckwheat decrease pest numbers, increase predation, and increase numbers of O. insidiosus in bell peppers (Bickerton and Hamilton 2012). Various species of wildflowers in Florida serve as hosts for the minute pirate bug and other natural enemies. These include Bidens alba (L.), sunflowers, and others. Many of these plants also host populations of the native non damaging thrips which may outcompete F. occi dentalis (Bottenberg et al. 1999, Northfield et al. 2008, Shirk et al. 2011). Plantings of these plants near crops of fruiting vegetables increase biological control of thrips (Frantz and Mellinger 2009). Companion plantings of these species are not source s for damaging populations of F. occidentalis as they are outcompeted by the

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94 native thrips species and they suffer preferential predation by minute pirate bugs. Companion plants such as those mentioned may serve to increase natural predators and competitor s of F. occidentalis and reduce populations of F. occidentalis in a vegetable field. The current study seeks to develop a novel, sustainable method of thrips management by combining the above components into a push pull method of thrips management. The pu sh pull method is grounded in behavioral manipulations involving a repulsive stimulus (push) to repel insects from crops and an attractive (pull) stimulus to attract the pests to an alternate source from which they can be removed or controlled (Cook et al. 2007). This method was successful in managing stemborer pests in Kenya in a maize crop system (Khan et al. 2001). Using a combination of repellant (push) and attractive (pull) weed plants, the combination developed in this system increased yield, increase d parasitism of stemborers by parasitoids, and reduced damage to maize by the competitiv e weed Striga (Khan et al. 2001, Khan et al. 2008a). The current study combines the technologies of ultraviolet reflective mulch and kaolin clay to act as push stimuli on the thrips pests, and companion plants of the native plant, B. alba to act as the pull stimulus for the thrips pests while also attracting and conserving the minute pirate bug. The objectives were to determine the separate and interactive effects of e ach component on the abundance and population dynamics of Frankliniella species, O. insidiosus and the yield and quality of pepper.

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95 Materials and Methods Plot establishment and maintenance These experiments were conducted with funding from a FDACS spe cialty crop block grant number 016856. Experiments were conducted at North Florida Research and Education Center located at 155 Research Rd, Quincy, Florida 32351. Experiments were conducted in the to ( Solanum lycopersicum ) plants and companion plants of Spanish needles ( B. alba ). Six week old tomato and B. alba plants were transplanted into the field on the same day. Dead plants were replaced as needed within the next two weeks. The plants were pro duced on raised beds 10 cm in height and 91.4 cm in width with 1.83 m spacing between beds. Beds were treated before mulch application with Dual Magnum (Syngenta Crop Protection LLC, Greensboro, NC 27419) at 1.2 kg active ingredient per ha for weed control A trickle tube placed under the mulch was used to irrigate based on plant needs. Plots were fertilized with 204, 29, and 170 kg/ha of N, P, and K, respectively to maintain growth of the plants. Pesticides for pests other than thrips were applied on an as needed basis. Weeds were pulled by hand and sprayed with Paraquat. Six week old tomato and B. alba transplants were planted in the plastic on 29 March 2011 and on March 27, 2012. Resets of B. alba and Tomatoes were done on April 6 and April 9 2012.A ran domized complete block split split plot design was used. Whole plot treatments consisted of ultraviolet reflective mulch and black polyethylene mulch (Berry Plastics Corp., Evansville, IN 47706), subplot treatments consisted of Surround WP Kaolin clay (Eng elhard Corp., Iselin, NF 08830) applications and a

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96 control, and sub sub plot treatments consisted of companion plantings of B. alba and a control (See Appendix). Kaolin clay was applied using a CO 2 backpack sprayer equipped with five D7 nozzles per row. Th e volume of water applied after being mixed with the kaolin was 48 gallons per acre at a pressure of 40 psi. Applications of kaolin were made two times per week as a spray at a rate of 5.7 kg per acre. Kaolin was applied on 22, 26, and 29 April; 3, 6, 10, 13, 17, 20, 24, 27 and 31 May; and 3 June 2011. In 2012 kaolin was applied on 30 April; 3, 7, 10, 15, 17, 21, 24, 29, 31 May; 4, 6 June. There were three replicates in this experiment. Each sub sub plot consisted of four beds 9.1 m in length. Each bed con sisted of one row with 45 cm spacing b etween plants for a total of 80 tomato plants per sub sub plot. Companion plants of B. alba were planted in one bed on each side on the outside rows of the tomato beds for two beds of B. alba per sub sub plot with comp anion plants. The companion plants were planted using a pepper wheel to punch holes in the plastic with a single drip tube down the center of the mulch. Two rows of B. alba were planted in each of the two external beds with 30 cm spacing between plants for a total of 128 B. alba plants in each sub sub plot in the companion plant condition. Insect Sampling Two samples of ten tomato flowers were randomly collected from each sub sub plot on each sample date. Samples were collected twice weekly from the begin ning of flowering until near the end of the production season. Two random samples of 10 B. alba flowers were collected on each sample date from each sub sub plot with companion plants. Flowers were placed immediately into vials containing 70% ethanol.

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97 Thri ps and other insects were extracted from the flowers in each sample and the insects were identified under a stereoscope with 40 X magnification. The total number of adult male s and females of each species of thrips ( F. occidentalis F. bispinosa F. tritic i F. fusca ), total thrips larvae, and adult and nymphal Orius insidiosus were determined. There were a total of 13 sample dates in 2011 and 12 sample dates in 2012. Yield Ten plants from each of the center rows (total of 20 plants) in each sub sub plot we re harvested starting in mid June in both years. Tomatoes of marketable size were counted, weighed, and graded for marketability. Tomato fruits exhibiting signs of thrips damage were culled in both years. In 2012 a large population of armyworms caused a h igh amount of damage to the tomatoes. Tomatoes displaying armyworm damage were not culled out in the first or third harvest, but were culled out in the second harvest. Tomato fruits were harvested on 22 and 30 June 2011 and on 19, 26 June, 12 July in 2012. Data Analysis Insect populations: The number of thrips larvae per adult Frankliniella spp. was determined on each sample date for each treatment and plant. Ratios of < 1, 1, and > 1 were considered to indicate a declining, stable, and increasing populatio n, respectively (Northfield et al. 2008). The ratio of total thrips (adults and larvae) per O. insidiosus was determined for each treatment and plant on each sample date. The predator is capable of suppressing a thrips population at a ratio of 1 predator p er 217 thrips (Sabelis and van Rijn 1997).

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98 Differences between treatments in numbers of male and female F. bispinosa thrips larvae, and O. insidiosus nymphs on tomatoes and B. alba separately were analyzed using analysis of variance for a randomized compl ete block design for a split split plot treatment arrangement in 2012 (PROC GLIMMIX, SAS Institute 2008). Response variables were transformed as needed and each analysis performed using the appropriate distribution for best fit. Differences in yield betwe en treatments were analyzed with ANOVA using the GLIMMIX procedure. The distributions for each yield variable were normal, so the analyses were conducted on the original data. Results The composition of thrips species in tomatoes was different in 2011 tha n in 2012. In 2011 F. tritici was the dominant species, accounting for 71% of thrips species found in tomato flowers. The second most common thrips in pepper flowers in 2011 was F. occidentalis (24%) with Frankliniella bispinosa only accounting for 5% of t otal thrips found. T he most common thrips in 2012 was F. bispinosa accounting for 73% of the thrips found, with F. tritici found in the second highest numbers (16%) and F. occidentalis was the least common of these three species in 2012 (10%). Numbers of F. fusca were negligible in both years. The mean number ( + SEM) of all adult thrips was higher in 2012 (29.5 1.2 per 10 flowers) than in 2011 (18.5 0.8 per 10 flowers). The seasonal mean ( + SEM) of F. tritici was higher in 2011 (13.1 0.7 per 10 flowers) than in 2012 (4.8 0.2 per 10 flowers). Mean ( + SEM) numbers of F. bispinosa were much lower in 201 1 (0.9 0.1 per 10 flowers) than in 2012 (21.6 1.0 per 10 flowers). Mean ( + SEM) numbers of F. occidentalis were similar in 2011 (4.4 0.2 per 10 flowers) and 2012

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99 (3 .0 0.1 per 10 flowers). Larvae were found in lower numbers in 2011 (4.9 0.3 per 10 flowe rs) than in 2012 (7.7 0.3 per 10 flowers). The mean ratios of thrips larvae to thrips adults in tomatoes and B. alba in 2011 and 2012 are shown in tables 3 1 and 3 2, respectively. Populations of thrips were decreasing on tomatoes for most of the 2011 season until the final two weeks of samples, at which point the populations appeared to be increasing. A similar pattern was observed in 2012. In both years, thrips popul ations were never increasing or stable on B. alba Population fluctuations of adult thrips on tomatoes in plots with and without B. alba companion plants during 2011 and 2012 are shown in Figures 3 1 and 3 2, respectively. Populations of all species of thr ips were initially low. Populations of F. tritici reached a peak during the third week of sampling, in mid May. After this peak the numbers of F. tritici were decreasing for the remainder of the season. Populations of F. occidentalis and F. bispinosa expe rienced an initial peak in numbers during the second week of sampling in early May, followed by a decrease in numbers with a major peak in population occurring in late May and early June. In 2012, F. tritici numbers displayed a similar pattern as in 2011, with a peak occurring in mid May. Populations of F. occidentalis also displayed a similar pattern in 2012 to the pattern observed in 2011. Numbers peaked in the second week of May with a later peak at the end of May and beginning of June. Contrary to the p attern observed in 2011, F. bispinosa reached peak numbers congruent to the peak in F. tritici in the middle of May. Seasonal trends in the abundance of thrips larvae in 2011 and 2012 are shown in Figures 3 3 and 3 4, respectively. In 2011, numbers of th rips larvae were initially low

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100 with a peak occurring on 17 May. In 2012, initial larval numbers were higher than they were in 2011. Numbers of larvae in 2012 reached an initial peak on 16 May followed by a second peak on 22 May. Peak numbers in both years were followed by a gradual decline for the remainder of the season. Numbers of the adult and nymphs of predator O. insidiosus were e xtremely low in both 2011 (0.1 0.0 per 10 flowers) and 2012 (0.2 0.0 per 10 flowers). The mean ratios of thrips to Orius in tomatoes and B. alba in each treatment in 2011 and 2012 are shown in Tables 3 3 and 3 4, respectively. Predators were often absent in tomatoes. Where predators were present on tomatoes and B. alba they were always present in ratios sufficient for suppress ion of thrips with the exception of one data point on B. alba in 2011. The numbers of predators on tomatoes were too low for further analysis. There were eight treatments in this experiment. These were a factorial of the two mulches, companion plants/no co mpanion plants, and kaolin/no kaolin. The results of the ANOVAs evaluating the main and interactive treatment effects of mulch, companion plants, and kaolin on numbers of adult and larval thrips of each species in tomato flowers for individual sample dates in 2011 and 2012 are shown in Tables 3 5 and 3 6, respectively. At the beginning of the season in 2011 F. tritici females were significantly higher in plots with companion plants than those without (Figure 3 1). Towards the end of the season, however, the presence of companion plants resulted in signi fi cantly fewer F. tritici males, and F. occidentalis females and males compared to plots without companion plants. Numbers of F. bispinosa females and males were also lower in plots with companion plants in 20 11, though this difference was not significant. Companion

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101 plants did not have an effect on the abundance of larvae in tomato samples in 2011 (Figure 3 3). Companion plants had a similar effect on thrips in 2012. Numbers of F. tritici females, and F. bispin osa males and females were significantly higher in plots with companion plants than in those without at the beginning of the season (Figure 3 2). The presence of companion plants resulted in significantly fewer female and male F. tritici and F. bispinosa t han tomatoes alone during the middle of the season in 2012 (Figure 3 2). Companion plants also decreased the numbers of F. occidentalis males at the end of the season in 2012 (Figure 3 2). Companion plants did not have an effect on F. occidentalis females in 2012. Companion plants significantly increased the number of thrips larvae on one date at the beginning of the season in 2012 (Figure 3 4). Kaolin reduced thrips numbers on tomatoes in 2011 and 2012. In 2011 this reduction was significant from the middl e to the end of the season (Figure 3 5). This effect was significant on F. tritici males and females, F. occidentalis males and F. bispinosa females. Kaolin significantly decreased numbers of thrips larvae at the end of the season in 2011 (Figure 3 3). In 2012 the reduction in thrips numbers by kaolin was significant from the beginning to the middle of the season (Figure 3 6). This effect was significant for F. tritici and F. bispinosa males and females. Kaolin did not have a significant effect on F. occide ntalis males or females in 2012. Numbers of thrips larvae were significantly lower on plants in the kaolin condition on one date early in the season in 2012 (Figure 3 4). The use of ultraviolet reflective mulch significantly reduced the numbers of F. tri tici and F. occidentalis males and females early and mid season in 2011 (Figure 3 7).

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102 Mulch did not significantly affect numbers of male or female F. bispinosa (Figure 3 7) or thrips larvae (Figure 3 3) in 2011. The use of ultraviolet reflective mulch redu ced the numbers of thrips on tomatoes in the beginning and mid season in 2012. However, this reduction did not reach significance with the exception of F. bispinosa males on 8 May (Figure 3 8). The effect of mulch on thrips larvae in 2012 also did not reac h significance, and resulted instead in a non significant increase in the number of larvae in tomato flowers (Figure 3 4). There was a significant mulch*kaolin interaction effect on the numbers of female F. tritici on tomatoes on 10 May 2011. On this date the highest mean ( SEM) number of female F. tritici were found in the black mulch condition (30.67 3.50), followed by the ultraviolet reflective mulch condition (17.42 2.94) with the fewest thrips found in the black mulch with kaolin (8.92 2.24) and ultra violet reflective mulch and kaolin (7.58 1.11) conditions. This interaction also had a significant effect on the number of male F. tritici found on tomato flowers on 5 and 10 May 2011. On 5 May the highest mean ( SEM) number of F. tritici males were found in tomato flowers in the black mulch with no kaolin condition (18.17 2.00) followed by the black mulch with kaolin condition (6.75 1.48). The lowest mean ( SEM) number of F. tritici males were found in the reflective mulch and kaolin (2.75 0.58) and the r eflective mulch only condition (2.67 0.43). On 10 May the highest mean ( SEM) number of F. tritici males were found in tomato flowers in the black mulch only condition (34.83 3.68). The second highest mean ( SEM) number of F. tritici males were found in to mato flowers in the ultraviolet reflective mulch only condition (12.00 1.99). The lowest numbers were found in the

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103 black mulch with kaolin (9.92 1.79) and the ultraviolet reflective mulch with kaolin (7.42 1.76) conditions. The mul ch*kaolin interaction e ffect also reached significance in 2012. On 16 May kaolin reduced the number of female F. tritici to a greater degree on ultraviolet reflective mulch (4.00 0.43 mean thrips in the kaolin condition, 8.42 1.20 without kaolin) than on black mulch (9.67 0.86 mean thrips in the kaolin condition, 9.75 1.48 without kaolin). There was also a significant interaction of mulch and kaolin on the number of female and male F. occidentalis found on the tomatoes in May 2012. Kaolin increased the number of male and femal e F. occidentalis found in the black mulch condition, while decreasing the number in the ultraviolet reflective mulch condition. On 8 May the mean ( SEM) numbers of F. occidentalis females in each sample were as follows: 4.33 0.70 in the black mulch only c ondition, 6.67 0.71 in the black mulch with kaolin condition, 6.17 1.04 in the ultraviolet reflective mulch only condition, and 3.75 0.45 in the ultraviolet reflective mulch with kaolin condition. On 25 May the mean ( SEM) numbers of F. occidentalis female s in each sample were as follows: 0.50 0.15 in the black mulch only condition, 2.17 0.49 in the black mulch with kaolin condition, 1.67 0.26 in the ultraviolet reflective mulch only condition, and 1.42 0.26 in the ultraviolet reflective mulch with kaolin c ondition. On 22 May the mean ( SEM) numbers of F. occidentalis males in each sample were as follows: 0.67 0.22 in the b lack mulch only condition, 1.42 0.54 in the black mulch with kaolin condition, 1.58 0.38 in the ultraviolet reflective mulch only condi tion, and 0.50 0.19 in the ultraviolet reflecti ve mulch with kaolin condition.

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104 There was a significant interaction effect of mulch and companion plants on the numbers of F. tritici males and thrips larvae in 2011 and on the numbers on F. bispinosa males a nd thrips larvae in 2012. In each of these instances the presence of companion plants reduced thrips numbers on black mulch, but increased numbers on ultraviolet reflective mulch. This interaction effect was significant on F. tritici males on 24 May 2011 r esulting in the following mean number F. tritici males per sample: 4.92 1.25 in the black mulch only condition, 2.00 0.43 in the black mulch with companion plants condition, 1.00 0.28 in the ultraviolet reflective mulch only condition and 1.42 0.38 in the ultraviolet reflective mulch with companion plants condition. The interaction significantly affected numbers of thrips larvae found in tomato flowers on 26 May and 2 June 2011. On 26 May the mean ( SEM) numbers of thrips larvae per sample were as follows: 6.33 1.19 in the black mulch only condition, 4.50 0.95 in the black mulch with companion plants condition, 4.58 0.94 in the ultraviolet reflective mulch only condition and 6.83 1.22 in the ultraviolet reflective mulch with companion plants condition. On 2 June the mean ( SEM) numbers of thrips larvae per sample were as follows: 9.75 2.27 in the black mulch only condition, 12.58 1.52 in the black mulch with companion plants condition, 14.17 2.39 in the ultraviolet reflective mulch only condition and 9.42 2.6 7 in the ultraviolet reflective mulch with companion plants condition. In 2012 the interaction between mulch and companion plants significantly affected numbers of F. bispinosa males and thrips larvae. On 8 May the mean ( SEM) numbers of F. bispinosa males per sample were as follows: 12.42 2.01 in the black mulch only condition, 6.83 1.26 in the black mulch with companion plants condition,

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105 3.17 0.96 in the ultraviolet reflective mulch only condition and 4.00 1.01 in the ultraviolet reflective mulch with com panion plants condition. On 18 May the mean ( SEM) numbers of thrips larvae per sample were as follows: 9.92 1.94 in the black mulch only condition, 8.00 1.53 in the black mulch with companion plants condition, 9.50 3.16 in the ultraviolet reflective mulch only condition and 15.33 4.18 in the ultraviolet reflective mulch with companion plants condition. There was a significant interaction effect of companion plants and kaolin on F. tritici females on two dates and on F. tritici males on one date in 2011. Fo r the females the presence of companion plants reduced numbers where no kaolin was used (16.42 2.41 with companion plants, 24.42 3.10 with no companion plants), but increased numbers of female F. tritici where kaolin was used (14.17 2.05 with companion pla nts, 11.92 1.60 with no companion plants) on 19 May. The same pattern was observed on 7 June, although to a smaller degree: 2.42 0.53 female F. tritici in the kaolin without companion plants condition, 2.67 0.48 in the kaolin with companion plants conditio n, 3.17 0.59 in the no kaolin with companion plants condition, 6.33 1.55 in the control condition. The companion plant and kaolin interaction affected the numbers of male F. tritici differently than the females. The presence of companion plants reduced th e number of male F. tritici found on tomatoes in the kaolin plots (Mean SEM=8.33 1.97 with companion plants, 9.00 1.63 without companion plants), but increased the number found in the plots without kaolin (Mean SEM=24.33 3.27 with companion plants, 22.50 5 .51 without companion plants). This interaction had a different effect on F. tritici

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106 females on 16 May 2012. Kaolin decreased numbers of female F. tritici in plots without companion plants (Mean SEM=7.50 1.17 with kaolin, 12.17 1.26 without kaolin), but in creased numbers of female F. tritici in plots with companion plants (Mean SEM= 6.17 0.97 with kaolin, 6.00 0.63 without kaolin). The interaction of mulch, kaolin and companion plants also produced significant effects. In 2011 this interaction significantl y affected F. tritici females on three dates. The effect revealed that the largest reduction in numbers of F. tritici females could be attained by using kaolin with black mulch and either kaolin or a combination of kaolin and companion plants on ultraviole t reflective mulch. The means ( SEM) in each treatment on 10 May 2011 in decreasing order were: 41 6.09 in the black mulch plots, 37.5 3.94 in the black mulch/companion plants plots, 22.17 3.99 in the ultraviolet reflective mulch/companion plants plo ts, 17.83 2.86 in the black mulch/kaolin/companion plants plots, 10.83 1.64 in the ultraviolet reflective mulch/kaolin plots, 8.33 2.23 in the black mulch/kaolin plots, 8.33 1.76 in the ultraviolet reflective mulch plots, and 7.5 1.28 in the ultr aviolet reflective mulch/kaolin/companion plants plots. On 12 May 2011 the means ( SEM) in decreasing order were: in the 37.5 10.74 black mulch plots, 23.83 3.1 in the black mulch/companion plants plots, 20.33 4.37 in the ultraviolet reflective mulch /companion plants plots, 14.5 2.2 in the ultraviolet reflective mulch plots, 11.83 2.33 in the black mulch/kaolin/companion plants plots, 7.83 1.74 in the ultraviolet reflective mulch/kaolin/companion plants plots, 7.33 2.22 in the ultraviolet refl ective mulch/kaolin plots, and 6 1.59 in the black mulch/kaolin plots. On 17 May 2011 the

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107 means ( SEM) in decreasing order were: 39.67 6.87 in the black mulch plots, 19.17 3.44 in the black mulch/companion plants plots, 18 4.52 in the ultraviolet r eflective mulch/companion plants plots, 17.83 3.96 in the black mulch/kaolin/companion plants plots, 13.67 4.94 in the black mulch/kaolin plots, 11.83 0.87 in the ultraviolet reflective mulch plots, 11.5 3.05 in the ultraviolet reflective mulch/kao lin plots, and 10.17 1.78 in the ultraviolet reflective mulch/kaolin/companion plants plots. This interaction affected numbers of F. tritici males in 2011 similarly to the females. The lowest numbers of F. tritici males were found in plots with black mu lch and kaolin or reflective mulch, kaolin, and companion plants. The mean ( SEM) numbers of F. tritici males in descending order on 10 May 2011 are as follows: 37.33 6.65 in the black mulch plots, 32.33 3.59 in the black mulch/companion plants plots, 16.33 2.92 in the ultraviolet reflective mulch/companion plants plots, 13.17 2.64 in the black mulch/kaolin/companion plants plots, 11.33 2.58 in the ultraviolet reflective mulch/kaolin plots, 7.67 1.2 in the ultraviolet reflective mulch plots, 6.6 7 1.71 in the black mulch/kaolin plots, and 3.5 0.89 in the ultraviolet reflective mulch/ kaolin/companion plants plots. The effect of this interaction on F. tritici males was also significant on 17 May 2011 with a similar pattern. The mean ( SEM) numb ers of F. tritici males in tomato flowers on 17 May 2011 in descending order are as follows: 20 2.97 in the black mulch plots, 11.83 2.27 in the black mulch/companion plants plots, 7.33 1.74 in the black mulch/kaolin/companion plants plots, 6 1.03 in the ultraviolet reflective mulch/companion plants plots, 5.83 1.49 in the black mulch/kaolin plots, 4.67 0.95 in

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108 the ultraviolet reflective mulch plots, 3.5 1.06 in the ultraviolet reflective mulch/kaolin plots, and 3.17 0.87 in the ultraviolet reflective mulch/kaolin/companion plants plots. In 2012 the effect of the mulch, kaolin, companion plant interaction was only significant on one date for one variable. The interaction significantly affected the number of thrips larvae on tomato flowers on 16 May 2012. Kaolin and companion plants increased numbers of thrips larvae on ultraviolet reflective mulch, and decreased thrips larvae on black mulch. The mean ( SEM) numbers of thrips larvae in tomato flowers on in descending order are as follows: 25.5 7.44 in the ultraviolet reflective mulch/companion plants plots, 15.33 1.45 in the black mulch plots, 11.67 3.78 in the ultraviolet reflective mulch/kaolin plots, 11.17 3.08 in the black mulch/kaolin/companion plants plots, 10 2.83 in the ultravi olet reflective mulch/kaolin/companion plants plots, 9 3.28 in the black mulch/ kaolin plots, 8.67 2.4 in the black mulch/companion plants plots, and 8 2.14 in the ultraviolet reflective mulch plots. The results of the ANOVAs evaluating the main an d interactive treatment effects of mulch and kaolin on numbers of adult and larval thrips of each species and Orius adults and nymphs in B. alba flowers for individual sample dates in 2011 and 2012 are shown in Tables 3 7 and 3 8, respectively. There were few significant effects on insect numbers in the B. alba flowers. Significantly more female F. tritici were found on B. alba flowers in the ultraviolet reflective mulch plots (Mean= 55.75 2.29) than in the black mulch plots (Mean= 38.00 1.95). There were n o other significant effects of mulch.

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109 There was a significant effect of kaolin on O. insidiosus on 10 May 2011. Significantly fewer O. insidiosus were found on B. alba flowers in plots with kaolin (Mean= 5.33 0.62) than in plots without kaolin (Mean= 7.08 1.22). Apart from these main effects the interaction of mulch and kaolin significantly affected F. tritici females and O. insidiosus in 2011 and F. bispinosa females, F. tritici females and thrips larvae in 2012 though only on one date for each of these. O n 7 June 2011 kaolin decreased the number of female F. tritici found on B. alba flowers in the black mulch condition (Mean=30.67 4.29 with kaolin, 45.33 3.63 without kaolin), but increased the number in the ultraviolet reflective mulch condition (Mean= 61.33 8.26 with kaolin, 50.17 5.15). The same pattern was observed for O. insidiosus on 10 May 2011. Fewer O. insidiosus were found on B. alba flowers in the black mulch with kaolin plots (Mean=4.67 0.99) than in the black mulch only plots (Mean=9.67 1.45) whereas more O. insidiosus were found in ultraviolet reflective mulch and kaolin plots (Mean=6 0.73) than in the ultraviolet reflective mulch only plots (Mean=4.5 1.34). In 2012 the interaction affected F. bispinosa females similarly (Mean= 40 3.48 in black mulch with kaolin plots, 58.67 6.56 in the black mulch only plots, 46.33 4.44 in the ultraviolet reflective mulch with kaolin plots, 37.5 1.41 in the ultraviolet reflective mulch only plots). The interaction of mulch and kaolin had the opposite effect on F. tritici females and larvae in 2012. Kaolin increased numbers of F. tritici on black mulch (Mean=27.67 3.81 with kaolin, 20 1.57 without kaolin) and decreased their numbers on ultraviolet reflective mulch (Mean=14.33 1.2 with kaolin, 18.67 2.86 without kaolin). This effect was similar on thrips larvae in 2012 (Mean= 2.83 0.95 in the black mulch with kaolin

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110 plots, 1.17 0.48 in the black mulch without kaolin plots, 1.17 0.48 on ultraviolet reflective mulch with kaolin, 2 .83 0.75 on ultraviolet reflective mulch without kaolin). The means ( SEM) of the yield of marketable and unmarketable tomato fruits and the results of the ANOVAs evaluating main and interactive effects of mulch, kaolin, and companion plants for 2011 and 2012 are shown in tables 3 9 and 3 10, respectively. The effect of companion plants on yield was consistent between years. In 2011 and 2012 the presence of B. alba companion plants significantly increased yield (number and weight) of medium and large mar ketable tomatoes (Tables 3 9 and 3 10). Mulch significan tly affected yield in 2011 only. Ultraviolet reflective mulch increased the yield of marketable extra large fruits on the second harvest date and the season total of large fruits (Table 3 9). In 2011 a significant effect of the kaolin and companion plant interaction led to increased yields of large fruits when both were used together, with decreased yields occurring when only kaolin was used (Table 3 9). The interaction of companion plant and mulch sig nificantly affected the season total number of large fruits indicating a greater increase in yield with companion plants in the ultraviolet reflective mulch plots than in the black mulch plots. There were no other significant effects in 2011. In 2012 compa nion plants significantly increased the number and weight of marketable medium and large tomatoes on the first two harvests (Table 3 10). On 26 June the interaction of companion plants and mulch significantly affected the number of large tomatoes harvested (Table 3 10). Companion plants increased yield on ultraviolet reflective mulch plots to a greater extent than in black mulch plots, where the yield was

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111 increased slightly and in one case decreased by the presence of companion plants. No other effects were significant. Discussion Increasing populations of thrips were not present on tomato or B. alba with both plants only supporting decreasing thrips populations in both years of the experiments. This confirms that neither of these plants serve as adequate re productive hosts for the three species of Frankliniella thrips in the study (Baez et al. 2011, Frantz and Mellinger 2009). Populations of F. occidentalis reached their peak in tomatoes corresponding to those times when F. tritici numbers were low in 2011 a nd 2012. In 2012 F. bispinosa numbers were much higher due to an abnormally mild w inter in n orth Florida and they were able to outcompete F. occidentalis This suggests an effect of interspecies competition between the three species, with F. tritici outcom peting F. occidentalis This confirms the findings of (Paini et al. 2008) who found that native species of thrips outcompete the invasive F. occidentalis Populations of O. insidiosus on tomatoes and B. alba in this experiment were low and sometimes absent However, when O. insidiosus were present in the flowers they were present at ratios sufficient for suppression of thrips. The presence of O. insidiosus in these ratios in this experiment indicate the ability of O. insidiosus to reach levels appropriate f or suppression when insecticides are not used (Funderburk et al. 2000). While companion plants initially increased the number of thrips on tomatoes, they produce a reduction in numbers of adult thrips throughout the season for F. tritici F. occidentalis a nd F. bispinosa (non significant). Companion plants did not affect larvae due to the inability of la rvae to choose their host plant. Larvae must live on the plant

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112 where they are oviposited. As neither of these plants are preferred hosts, oviposition behavi or would not be expected to be affected Kaolin reduces thrips numbers from the middle to the end of the season, in agreement with previous studies (Spiers et al. 2004, Larentzaki et al. 2008). This reduction included F. tritici, F. bispinosa, and males of F. occidentalis which differs from a previous study finding no effects on F. occidentalis or F. bispinosa ( Reit z et al. 2008). The mechanism behind the reduction in thrips numbers in this study is unknown, but could be combination of reasons. As suggeste d in previous studies this reduction could be due to reflective properties of the clay, deterrence to oviposition an d feeding by thrips, delay of larval development time and increase of mortality to thrips (Larentzaki et al. 2008, Peng et al. 2010). Althou gh kaolin clay may reduce predator numbers, predators are able to rebound after kaolin treatments are terminated (Marko et al. 2008). Orius can quickly reinvade a field after pesticide applications are terminated (Ramachandran et al. 2001) and would likely also increase in number once kaolin treatments have ended and in high enough numbers to control thrips. Kaolin clay treatments at the beginning of the season can suppress thrips numbers and keep them low until Orius numbers are high enough in B. alba to c ontrol thrips in the field, at which time kaolin applications can be terminated. Additionally, previous studies indicate that later applications of kaolin clay are not more beneficial, suggest that ending applications mid season (Spiers et al. 2004) will s ave resources without reducing the reduction of thrips Kaolin is also used on plants to reduce plant stress from temperature, and late season applications are not as beneficial for decreasing plant stress (Creamer et al. 2005).

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113 In 2012 kaolin decreased F. tritici females and F. occidentalis males and females on ultraviolet reflective mulch while increasing their numbers on black mulch. This increase on black mulch may be due to the kaolin reducing temperatures on the plants (Cantore et al. 2009) thereby creating a more hospitable environment in terms of temperature for the thrips. However, this effect was only observed on one date and may be of no practical or repeatable importance. Ultraviolet reflective mulch significantly decreased thrips in 2011 but not in 2012. The reason for this inconsistency is unknown but could be due to different species composition in 2012, or different solar radiation in the two years affecting the amount of light reflected from the mulch. However, previous studies indicated c onsistent reductions in the numbers of adult thrips when ultraviolet reflective mulch is used (Greenough et al. 1990, Greer and Dole 2003, Reitz et al. 2003, Riley et al. 2012) suggesting that the results in 2012 are aberrant. One study on bell peppers fou nd that thrips were not affected by plastic mulch types (Diaz Perez, 2010), however this study did not identify thrips to species and may have missed key species differences in response to mulch. In 2012 the key thrips species in the tomato flowers were F. occidentalis and F. tritici in 2011 the main thrips species was F. bispinosa It is possible that these species respond differently to the mulch and F. bispinosa may not be deterred by the ultraviolet reflective mulch to the degree that the other two spe cies were affected in 2011. Importantly, ultraviolet reflective mulch only effectively reduces thrips early in the season before foliar growth and chemical residues have obscured the reflectance. After this happens other tactics are needed.

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114 Interactions b etween mulch and kaolin were sparse and inconsistent. The most common interaction resulted in the fewest thrips in the plots using both ultraviolet reflective mulch and kaolin. This indicates a potential synergistic activity between these two components. C ompanion plant and mulch interactions were also inconsistent and sparse, but seem to suggest that the highest numbers of thrips (larvae) are found in plots with companion plants and reflective mulch. It is possible that companion plants acted as a pull (aw ay from the tomatoes) in the black mulch condition but attracted insects into the plots in the ultraviolet reflective mulch plots, helping them to overcome the reflectance. Once a thrips lands on the ultraviolet reflective mulch the mulch is thought to hav e an arresting affect, preventing the thrips from leaving. Female thrips may then be more likely to oviposit onto these plants (Reitz et al. 2003). Three way interactions indicate the best reduction in thrips numbers can be procured using black mulch with kaolin, or reflective mulch with kaolin or reflective mulch with kaolin and companion plants. The effects of these components on yield must be considered, and the economics also considered, before a grower can decide which compo nents offer the greatest re turn on investment. The use of ultraviolet reflective mulch increased extra large fruits in this experiment, although this effect was not consistent between years. The increase in yield in 2011 is consistent with previous studies which found increased yiel d when using ultraviolet reflective mulches (Greer and Dole 2003, Reitz et al. 2003, Riley et al. 2012). The lack of increased yield in 2012 may be due to the low disease incidence. Previous studies found that yield is not affected in years of low disease incidence (Stavisky et al.

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115 2002, Riley et al. 2012) and one study found that yield of bell peppers is not influenced by mulch type during the spring season (Diaz Perez 2010). Both of these situations match the conditions from the 2012 experiment. Additiona lly, a mild 2011 2012 winter changed the species composition of thrips and other insects in the fields which also may have contributed to the lack of yield differences. It is expected in years with normal winters, during the fall season, and with high dise ase pressure to see a yield difference. Companion plants increased yield of medium and large fruits consistently. Companion plants increase yield more in the ultraviolet reflective mulch plots than in the black plots. The reason for this could be due to re duction in thrips damage by reduced thrips numbers, as the companion plants did significantly decrease thrips numbers. However, if this were true we would expect to see a difference in the unmarketable tomatoes harvested, which we did not find. Companion p lants may also increase yield in both plots by attracting wild pollinators to the field (Chaplin Kramer et al. 2011) and increasing pollination, thereby increasing fruit set. If this were the reason for increased yield, the yield of unmarketable tomatoes w ould be unaffected, as it was. Additionally, habitat complexity increases the richness and abundance of generalist natural enemies (Langellotto and Denno, 2004, Chaplin Kramer et al. 2011). This increase of generalist natural enemies could increase vertica l control of numerous species of pests in the same field. R eductions of other pest species and their resulting damage, which were not measured in this study, could also have contributed to the increased yield (Showler and Greenburg, 2002, Ghodani et al. 20 09). Future studies should measure all pest species and damage on the crop to determine whether such reductions occur.

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116 The larger increase in yield in ultraviolet reflective mulch plots when using companion plants than in the black mulch plots may be due to a reduction in pollinators in ultraviolet reflective mulch plots due to reflectance. Companion plants in these plots may help to overcome this problem, by attracting pollinators from a different angle to the field. As pollinators travel from flower to f lower the reflectance would not deter them if they travel from the B. alba to the tomatoes in the next row. Reduction of other pests and attraction of various other beneficial organisms to the field are also possible contributions to the increased yield an d have been found in previous studies (Robinson et al. 1972, Bickerton and Hamilton 2012) The effect of kaolin on yield is unclear. Use of kaolin may increase yield when used in combination with companion plants. In previous studies kaolin clay was found t o reduce total weight of harvested tomatoes (Kahn and Damicone 2008), and had no effect on yield of peanuts (Wilson et al. 2004), chile peppers (Creamer et al. 2005) or onions (Larentzaki et al. 2008). In another study, kaolin increased fruit set on bluebe rries, but decreased the size of the berries (Spiers et al. 2004). The current results are in agreement with those studies which did not find a difference in yield. Additionally, kaolin may not have affected yield in this experiment due to low disease inci dence (Reitz et al. 2008), similar to the effect seen with ultraviolet reflective mulches (Riley et al. 2012). Kaolin clay increases yield by reducing disease incidence rather than affecting thrips directly (Reitz et al. 2008). In years of higher disea se i ncidence kaolin may offer protection that is economical Kaolin clay consistently decreases thrips on tomatoes, but does not affect yield. Therefore, it is important for growers to consider the cost of the kaolin compared with the lack of increase in yield when considering whether

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117 to use this material on their fields. In areas or years of higher disease incidence it may increase yield (Creamer et al. 2005, Reitz et al. 2008, Riley et al. 2012). The conditions producing the greatest reduction in thrips numb ers likewise produced the greatest yield with the highest yields in 2011 being obtained from plots with ultraviolet reflective mulch, kaolin, and companion plants, or black mulch with ields obtained in the plots with ultraviolet reflective mulch, ultraviolet reflective mulch, kaolin, and companion plants, black mulch and companion plants, or black mulch and kaolin depending on the harvest date and tomato size. On B. alba kaolin decreas ed the number of thrips and O. insidiosus in the B. alba flowers. The kaolin was not applied to B. alba plants, only the tomatoes. Therefor the reduction may be due to direct mortality of insects in those plots, reducing the number of insects also on B. al ba The kaolin may also disguise the host plants (Bar Joseph and Frenkel 1983) thereby confusing insects and preventing both thrips and Orius from landing in those plots. This pattern is revers ed in the plots with ultraviolet reflective mulch. In these plo ts the numbers of insects were higher on B. alba when kaolin was used. In this case the kaolin may decrease the reflectivity of the mulch thereby reducing the number of insects repelled from those plots. However, these affects were intermittent in nature a nd the practical significance of these interactions is dubious. The presence of B. alba companion plants reduced thrips and increased yield of tomatoes in this experiment. However, a few practical questions involving the implementation of this component o f a pest management strategy remain to be answered. One of these questions is the scale at which this method can be increased to

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118 without losing functionality. In addition to the size of farms at which this method can function is the distance from the crop that these plants must be planted to be effective. Bickerton and Hamilton (2012) found that distance from flowers was not a significant factor for predation by O. insidiosus on Ostrinia nub ilalis If this is true it could solve another problem impeding imp lementation of this strategy loss of arable land for crops to be used instead for planting companion plants. If distance is not a significant factor, B. alba or other plants could be planted in the roads between blocks of crops, in rows between beds, at t he ends of rows, or even along the ditches in between blocks and around the farms. Many farms already have natural populations of B. alba growing along the ditches and other uncultivated areas (personal observation) and the growers could potentially save m oney on herbicides and pesticides by allowing these to remain growing rather than eliminating them with herbicides. If these plants are present before the crop is planted they may serve as a source for established beneficial insects including natural preda tors and pollinators. Additionally it remains to be determined what effect, if any, these companion plantings have on pollinators, other pest species, and other natural enemy species. More pollinators and natural enemies were observed in the plots with B. alba on the tomatoes and B. alba alike; however this was only an observation and was not quantified. Future studies would be prudent to measure these parameters. It would also be very useful to ascertain the effectiveness of these companion plants in redu cing pest species when compared directly to current common insecticide regimens. The pest reduction as well as return on investment should be measured in such a study to assist growers in determining which method to employ in their fields for the greatest profit. A

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1 19 combination of companion plants with selective insecticide applications should also be evaluated as a third possibility for use by growers. The results of this study revealed that the three components used in this method each provide benefits an d some disadvantages to growers. The most promising component for increasing yield and reducing thrips is the planting of B. alba in the field as companion plants. Ultraviolet reflective mulch reduces thrips numbers early in the season and increases yield and kaolin clay reduces thrips but does not increase yield. Kaolin clay may be a useful component to reduce thrips numbers after ultraviolet reflective mulch has lost its reflective effect and before predators are present in the field. Companion plants are effective and can be used with or without the other components. To determine which combination is the most beneficial to growers, however, certain questions remain to be answered. Future investigations should determine the economics of these different com ponents for increasing revenue without increasing investment. Future studies should consider disease pressure, as some of these components may be more appropriate and produce larger yield increases in years with higher disease incidence. Additionally, a co st comparison with common insecticides is needed. The effect of these components on other pest species and their damage, diseases, and beneficial insects should also be evaluated to ascertain the ability of these components to be used in vertically integra ted pest management programs. Lastly, this method should be evaluated at larger, commercial scale farms to determine the effect of scale on the efficacy of the components. Despite these gaps, the current research provides three effective and promising elem ents which can be used separately or in various combinations with each other and other pest management tactics to

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120 manage thrips and tospoviruses on tomatoes while reducing pesticides and delaying resistance development

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121 Table 3 1. The ratio of the total number of larval Frankliniella species to the total number of Frankliniella adults in the flowers of tomatoes planted without Bidens alba tomatoes planted with B. alba and B. alba on each sample date in the experiment conducted in 2011 in Gadsden County, Florida. Treatm ent 19 April 26 April 29 April 3 May 5 May 10 May 12 May 17 May 19 May 24 May 26 May 31 May 2 June 7 June Tomatoes alone B a b --c 0.16 0.08 0.05 0.01 0.01 0.32 0.16 0.28 0.39 0.37 1.45 1.24 B/K --0.12 0.09 0.02 0.02 0.01 0.52 0.32 0.59 0.68 0.78 0.62 1.80 R ----0.04 0.11 0.01 0.00 0.43 0.18 0.42 0.38 0.16 1.26 2.99 R/K ----0.33 0.09 0.02 0.00 0.39 0.26 0.83 0.45 0.25 1.40 1.61 Tomatoes with Bidens alba B --0.43 0.09 0.05 0.00 0.00 0.30 0.28 0 .45 0.39 0.72 1.86 2.59 B/K --0.12 0.07 0.06 0.00 0.00 0.53 0.27 0.79 0.55 0.51 2.00 2.28 R ------0.04 0.01 0.01 0.36 0.20 0.26 0.89 0.17 1.39 2.07 R/K ----0.17 0.03 0.01 0.02 0.43 0.31 0.82 1.06 0.60 0.92 4.08 Bidens alba B 0.33 0. 02 0 0 0 0 0 0.1 0 0.1 0.1 0.01 0.01 0.06 B/K 0 0.02 0 0.01 0.01 0 0 0 0 0 0.1 0.05 0.03 0.06 R 0 0.03 0 0 0 0 0 0 0 0 0 0.01 0.03 0.02 R/K 0 0 0.01 0 0 0 0 0 0 0 0 0.02 0.02 0.02 a B indicates plants planted on black mulch, K indicates kaolin clay and R indicates pepper plants planted on reflective mulch b indicates no samples collected on that date. c --indicates no adults present in the collections on that date.

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122 Table 3 2. The ratio of the total number of larval Frankliniella species to the total number of Frankliniella adults in the flowers of tomatoes planted without Bidens alba tomatoes planted with B. alba and B. alba on each sample date in the experiment conducted in 2012 in Gadsden County, Florida. Treatm ent 1 May 4 May 8 May 11 May 16 May 18 May 22 May 25 May 30 May 1 June 5 June 7 June Tomatoes alone B a 0.12 0.35 0.01 0.03 0.13 0.21 0.33 0.33 0.56 0.59 1.14 1.26 B/K 0.58 0.44 0.08 0.03 0.09 0.16 0.65 0.86 0.58 0.60 0.75 0.63 R 0.32 0.07 0.02 0.03 0.07 0.24 0.70 0.64 0.61 0. 43 0.84 0.70 R/K 0.85 0.25 0.08 0.05 0.15 0.18 0.41 0.70 0.66 0.25 1.69 1.13 Tomatoes with Bidens alba B 0.11 0.13 0.11 0.04 0.12 0.17 0.39 0.29 0.35 0.32 0.89 1.36 B/K 0.44 0.28 0.05 0.08 0.18 0.20 0.68 2.49 0.34 0.67 1.32 1.55 R 0.12 0.26 0.04 0.13 0.36 0.51 0.50 0.56 0.62 0.42 1.94 1.17 R/K 0.10 0.28 0.10 0.09 0.19 0.25 0.85 1.49 1.00 0.99 1.55 1.52 Bidens alba B 0.01 0.01 0.01 0.00 0.01 0.02 0.02 0.02 0.02 0.04 0.03 0.04 B/K 0.01 0.01 0.01 0.01 0.01 0.01 0.03 0.01 0.04 0.05 0.04 0.02 R 0.01 0.01 0.01 0.01 0.02 0.02 0.03 0.01 0.05 0.04 0.05 0.04 R/K 0.01 0.01 0.00 0.00 0.01 0.02 0.02 0.01 0.02 0.03 0.03 0.02 a B indicates plants planted on black mulch, K indicates kaolin clay and R indicates pepper plants planted on reflective mulch

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123 Table 3 3. The ratio of the total number of thrips adults and nymphs to the total number of Orius insidiosus adults and nymphs in the flowers of tomatoes planted without Bidens alba tomatoes planted with B. alba and flowers of B. alba on each sample d ate in the experiment conducted in 2011 in Gadsden County, Florida. Treatm ent 19 April 26 April 29 April 3 May 5 May 10 May 12 May 17 May 19 May 24 May 26 May 31 May 2 June 7 June Tomatoes alone B a b --c ------59.7 5 16.5 47.5 70 ----------B/K ----22 ----33 --50 ----23 9 --R --------16 40.5 18 45 --20 --30.5 43 R/K ----------36 --19.2 5 18.2 5 --26 24.5 --Tomatoes with Bidens alba B ----10 --60 59.5 6 64.6 7 ----19 30 12 B/K --------23 12 22.7 5 14.5 ------12.5 --R ------6 27.8 3 48 63 34.3 3 23 6.5 28 22 --R/K ----------19.6 7 --21 --------16.3 3 Bidens alba B ----95 140. 17 91.8 43.6 1 36.6 1 8.96 15.4 6 29.6 3 21.8 6 20.6 5 31.2 5 64.5 B/K --3 --99.2 5 68.7 98.8 9 63.6 5 11.8 12.5 7 25.5 8 15.9 2 18.2 5 28.2 5 21 R 0 --103.5 226. 25 74.1 85.6 8 43.3 9 13.6 4 20.3 6 17.9 16.7 1 22.4 40.2 8 49.6 R/K --8 94 192 60.7 56.5 7 34.6 9.76 32.4 1 41.7 5 13.3 7 14.4 6 29.9 6 51.4 2 a B indicates plants planted on black mulch, K indicates kaolin clay and R indicates pepper plants planted on reflective mulch b indicates c --indicates no Orius were present in the samples on the respective date

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124 Table 3 4. The ratio of the total number of t hrips adults and nymphs to the total number of Orius insidiosus adults and nymphs in the flow ers of tomatoes planted without Bidens alba tomatoes planted with B. alba and flowers of B. alba on each sample date in the experiment conducted in 2012 in Gadsd en County, Florida. Treatment 1 May 4 May 8 May 11 May 16 May 18 May 22 May 25 May 30 May 1 June 5 June 7 June Tomatoes alone B a --b --56.00 159.0 0 121.1 7 111.0 0 --37.00 37.00 ------B/K ------35.75 132.0 0 --40.00 --17.00 --15.00 16.00 R ----25.00 73.33 97.75 68.00 27.00 --13.50 ----12.00 R/K ------23.00 72.50 25.00 54.00 --------29.00 Tomatoes with Bidens alba B 60.0 0 28.50 61.00 65.00 77.25 50.00 41.00 ----14.00 --41.00 B/K --28.00 33.50 --83.00 47.00 ----11.00 --11.00 17.00 R ----20.50 48.25 88.17 60.00 ----30.00 ----33.00 R/K ------39.00 24.67 46.00 33.00 38.00 --39.00 7.00 --Bidens alba B 119. 74 62.85 20.23 16.20 23.71 15.87 19.53 25.19 47.78 25.27 43.19 4 7.88 B/K 84.0 2 60.28 17.91 15.63 15.75 14.42 13.80 24.68 20.25 38.64 52.00 36.04 R 63.0 9 87.09 29.21 22.31 20.88 19.05 19.76 17.36 27.74 42.70 55.69 23.43 R/K 124. 50 32.82 20.80 19.72 12.07 10.65 19.42 28.87 29.79 29.84 60.19 28.96 a B indicates plants planted on black mulch, K indicates kaolin clay and R indicates pepper plants planted on reflective mulch b --indicates no Orius were present in the samples on the respective date

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125 Table 3 5. F values for treatment effects in the ANOVAs conducted for individual 2011 sample dates to determine the effects of mulch, companion plants, and kaolin clay on the numbers of adults and larvae of F. bispinosa F. tritici and F. occidentalis species found in tomato flower in the experiment conducted in Gadsden Co unty, Florida. ANOVA treatment effect d.f. F value 26 Apr 29 Apr 3 May 5 May 10 May 12 May 17 May 19 May 24 May 26 May 31 May 2 Jun 7 Jun F. bispinosa adult females C 1, 8 n/a n/a n/a n/a n/a n/a 0.3 0.1 4 n/a 0.3 0.9 0.2 M 1, 2 n/a n/a n/a n/a n/a n /a 1.7 2.8 0 n/a 6 1.9 0.8 C x M 1, 8 n/a n/a n/a n/a n/a n/a 1.2 0.1 0.1 n/a 0.3 3.2 0.2 K 1, 4 n/a n/a n/a n/a n/a n/a 0 0.1 6.4 n/a 12.2* 14.7* 1.4 C x K 1, 8 n/a n/a n/a n/a n/a n/a 1.2 0.7 0.2 n/a 3 0 0.8 M x K 1, 4 n/a n/a n/a n/a n/a n/a 0.1 3.6 2.2 n/a 3.8 0.1 0.2 C x M x K 1, 8 n/a n/a n/a n/a n/a n/a 2.9 1.8 0 n/a 2.1 0.1 0 F. bispinosa adult males C 1, 8 n/a n/a n/a n/a n/a n/a 2.3 0.1 0.5 n/a n/a n/a n/a M 1, 2 n/a n/a n/a n/a n/a n/a 0.1 2 7.9 n/a n/a n/a n/a C x M 1, 8 n/a n/a n/a n/a n/a n/a 0 2.1 0 n/a n/a n/a n/a K 1, 4 n/a n/a n/a n/a n/a n/a 0.2 0.8 0.4 n/a n/a n/a n/a C x K 1, 8 n/a n/a n/a n/a n/a n/a 0 1 0.8 n/a n/a n/a n/a M x K 1, 4 n/a n/a n/a n/a n/a n/a 2.8 0.8 0 n/a n/a n/a n/a C x M x K 1, 8 n/a n/a n/a n/a n/a n/a 2 .5 0 0.1 n/a n/a n/a n/a F. tritici adult females C 1, 8 n/a 0.3 0 n/a 16.0** 1.5 0 1.6 0.2 0.1 0.1 1.9 2.8 M 1, 2 n/a 0.8 24.7* n/a 69.4** 4.2 4.2 23.1* 7.6 0.3 0 1.1 1 C x M 1, 8 n/a 0.2 0 n/a 0 0.1 0.7 0.1 1.8 0 0.4 0 2.8 K 1, 4 n/a 0 3.3 n/a 93.2* ** 50.8** 7.9* 22.1** 32.1** 7.4* 53.3** 27.7** 12.0* C x K 1, 8 n/a 0.2 0.5 n/a 2.4 2.9 0.6 9.9** 1.9 0 1.6 0 6.1* M x K 1, 4 n/a 2.4 0.2 n/a 21.5** 2.1 1 0.3 3.5 0.9 0.1 1 2.3 C x M x K 1, 8 n/a 1.4 0.5 n/a 46.8*** 5.9* 5.7* 0 0.2 0.6 0.5 0.1 0.8

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126 Table 3 5. Continued. ANOVA treatment effect d.f. F value 26 Apr 29 Apr 3 May 5 May 10 May 12 May 17 May 19 May 24 May 26 May 31 May 2 Jun 7 Jun F. tritici adult males C 1, 8 n/a 2.4 2.9 0.2 0.1 0.5 0.1 6.7* 0.2 0.2 n/a 0 n/a M 1, 2 n/a 1.9 27.2* 6 1.8* 42.9* 13.2 14.3 21.9* 6.6 0.9 n/a 0 n/a C x M 1, 8 n/a 0.3 0.8 0.1 4.1 1.1 0.8 3.8 5.9* 0.9 n/a 0.3 n/a K 1, 4 n/a 0.1 1.7 6.9 66.4** 34.0** 29.3** 25.1** 11.7* 21.9** n/a 10.3* n/a C x K 1, 8 n/a 0 0.2 0.4 5.5* 0 0.7 0 3.2 3.3 n/a 0.1 n/a M x K 1 4 n/a 5.5 1.7 8.0* 9.9* 2.6 2.6 0 0.9 0.3 n/a 0.5 n/a C x M x K 1, 8 n/a 0.3 0.2 0 34.1*** 0 5.1* 1.2 0 0.3 n/a 0 n/a F. occidentalis adult females C 1, 8 n/a 1.93 n/a 0.98 0 1.36 0 0.28 1.15 0.69 4.64 14.4** 2.3 M 1, 2 n/a 32.0* n/a 9.05 0.79 0.04 1 .08 0.06 0.5 0 0.94 5.19 3.26 C x M 1, 8 n/a 1.7 n/a 1.42 1.16 4.07 0.03 0.76 0.23 3.09 0.13 0.17 0 K 1, 4 n/a 0.37 n/a 1.16 0.3 0.23 2.28 0.71 0.5 1.46 0.1 5.61 3.1 C x K 1, 8 n/a 0 n/a 0.04 0.28 0.21 0.23 4.45 0.86 0.53 3.14 0.83 0.71 M x K 1, 4 n/a 0.37 n/a 0.27 2.35 2.92 0.2 2.26 2.91 5.15 3.41 4.87 0.3 C x M x K 1, 8 n/a 0 n/a 0.07 0.02 0.81 0.01 0.97 1.15 0.19 0.95 2.1 1.54 F. occidentalis adult males C 1, 8 n/a n/a 0.1 0.9 0 n/a 1.5 0.1 5.6* 5.3* 13.0** 7.8* 11.3** M 1, 2 n/a n/a 21.7* 5.2 0. 2 n/a 1.5 2.9 1 0.3 0.4 2.1 1.1 C x M 1, 8 n/a n/a 0 0.1 0 n/a 0.8 0.1 1 0.1 0.1 0.8 1.6 K 1, 4 n/a n/a 0.4 0 0.2 n/a 7.9* 2.7 3.9 3.2 6.3 2.5 7.4* C x K 1, 8 n/a n/a 1.5 0.5 0.2 n/a 0.8 0.6 0.4 0 3 1 0.3 M x K 1, 4 n/a n/a 0.6 0.4 0.2 n/a 0 1.6 2.1 0 0 0.2 0.5 C x M x K 1, 8 n/a n/a 3.2 0.3 0.2 n/a 0.2 0 1.1 0 0.1 0.1 3.4

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127 Table 3 5. Continued. ANOVA treatment effect d.f. F value 26 Apr 29 Apr 3 May 5 May 10 May 12 May 17 May 19 May 24 May 26 May 31 May 2 Jun 7 Jun Thrips larvae C 1, 8 n/a 0 n/a 0.1 n/a n/a 0.4 0.1 0.1 0.1 0.4 0.7 0.1 M 1, 2 n/a 3.1 n/a 3.4 n/a n/a 7.7 7.6 3.5 0 2.2 0 6.1 C x M 1, 8 n/a 0 n/a 0.6 n/a n/a 0.8 0.5 0.1 5.2* 1.2 9.5* 0.1 K 1, 4 n/a 0 n/a 1.1 n/a n/a 3.3 0.6 0.1 6.5 1.8 21.3** 7.3* C x K 1, 8 n/a 0 n/a 0.3 n/ a n/a 2.8 0 1 0.6 0 0.2 0 M x K 1, 4 n/a 3.8 n/a 2.3 n/a n/a 0 0 0.3 1.9 2.3 0.3 0.1 C x M x K 1, 8 n/a 0 n/a 1.1 n/a n/a 2.3 0.3 0.2 0 0.4 4.4 0.4 a C indicates effect of companion plants, M indicates mulch effects, K indicates kaolin clay effects. *, P < 0.05; **, P < 0.01; ***, P < 0.001

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128 Table 3 6. F values for treatment effects in the ANOVAs conducted for individual 201 1 sample dates to determine the effects of mulch, companion plants, and kaolin clay on the numbers of adults and lar vae of F. bispinosa F. tritici and F. occidentalis species found in tomato flowers in the experiment condu cted in Gadsden County, Florida. ANOVA treatment effect d.f. F value 1 May 4 May 8 May 11 May 16 May 18 May 22 May 25 May 30 May 1 Jun 5 Jun 7 Ju n F. bispinosa adult females C a 1, 8 6.1* 16.1** 1.1 n/a n/a 2.9 1.9 9.3* 2.6 0.5 1.5 1.2 M 1, 2 23.2* 7.9 4.8 n/a n/a 0 0.3 4.3 3.5 0.1 0 0 C x M 1, 8 0.7 1.3 4.9 n/a n/a 0 1 0 0.3 0.7 1.9 0.6 K 1, 4 15.2* 7.3* 42.4** n/a n/a 18.1* 5.7 11.9* 4.2 1.1 1.1 2.7 C x K 1, 8 0.4 0.1 1.6 n/a n/a 0.5 0.7 0.9 1.1 2.3 0.1 1.3 M x K 1, 4 1.5 0.6 0.6 n/a n/a 0 0.7 3.7 0 0.1 0.3 0.7 C x M x K 1, 8 0.5 1.7 0.4 n/a n/a 1.2 0.1 1.4 0.4 1 0.8 0 F. bispinosa adult males C 1, 8 n/a 5.5* 0.4 4.9 46.3*** 21.5** 8.8* 8 .1* 0.1 0.3 n/a 0.3 M 1, 2 n/a 11.6 28.9* 6.9 0.3 3.9 0.9 0.3 0 0.3 n/a 0.1 C x M 1, 8 n/a 0 5.6* 0.8 0.7 0.8 0.8 0 2.8 0.1 n/a 1.5 K 1, 4 n/a 5.1 23.0** 41.8** 21.5** 20.1** 0.8 4.9 4.8 2.1 n/a 6.3 C x K 1, 8 n/a 0.1 0.8 1.7 1.6 1.6 1.1 4.2 0.5 1.5 n/ a 1.1 M x K 1, 4 n/a 0 0.1 0.5 0.2 0.2 2.5 0.1 0.1 1.5 n/a 0.1 C x M x K 1, 8 n/a 2.5 0 0.2 0.7 0.2 0.4 0.1 0.3 0.1 n/a 0.2 F. tritici adult females C 1, 8 10.8** 5.3* 0.2 0.9 12.2** 0.6 7.1* 5 0.7 3.7 0 2.4 M 1, 2 13.2 4.2 2.8 7.8 15.5 1.1 0.5 1.9 3. 8 0.3 2.3 0 C x M 1, 8 0 0.5 3.9 0.3 2.5 0.1 0.1 4.3 0.5 0.1 0.2 0.2 K 1, 4 6 6.2 17.4** 32.1** 6.9 2.7 0.6 6.9 5 8.2* 0.4 0 C x K 1, 8 1.4 4.9 1 0.3 5.5* 0.5 0 0 1.5 2.4 1.7 3.5 M x K 1, 4 1.8 0 2.5 0.5 11.3* 0.5 0.8 1.6 0.8 1 0.4 1 C x M x K 1, 8 1 0.7 0.2 0.8 0.2 0 0.8 0 1.2 2.3 2.6 0.1

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129 Table 3 6. Continued ANOVA treatment effect d.f. F value 1 May 4 May 8 May 11 May 16 May 18 May 22 May 25 May 30 May 1 Jun 5 Jun 7 Jun F. tritici adult males C 1, 8 n/a 0.2 0 1.6 3.5 9.2* n/a n/a n/a n/a n /a n/a M 1, 2 n/a 3 2.7 1.1 11.9 1.2 n/a n/a n/a n/a n/a n/a C x M 1, 8 n/a 0 2.6 2.4 0 0.3 n/a n/a n/a n/a n/a n/a K 1, 4 n/a 1.3 12.4* 5.7 15.2* 4.6 n/a n/a n/a n/a n/a n/a C x K 1, 8 n/a 0.6 0.1 0.6 2.5 2.7 n/a n/a n/a n/a n/a n/a M x K 1, 4 n/a 3 0 7 0.3 1.1 n/a n/a n/a n/a n/a n/a C x M x K 1, 8 n/a 0 0.1 1.2 0.1 0.7 n/a n/a n/a n/a n/a n/a F. occidentalis adult females C 1, 8 0.4 2 0.2 0.9 1 1 2.4 2.8 1.3 2.8 1.7 3.8 M 1, 2 3.7 3.1 0.5 3 1.9 1.5 0.1 1.9 2.3 1.8 0.1 0.5 C x M 1, 8 0.5 0.5 0.5 0.2 2.4 4.9 2.3 0.1 0.5 0.1 1.2 0 K 1, 4 0 4.7 0 0.4 5 5.1 4.9 4.9 0 0.3 1.4 1.2 C x K 1, 8 0.5 1.9 1.3 0.1 0.3 0 1.1 0 0.7 1.1 0.3 1.2 M x K 1, 4 0.3 0 9.6* 2.8 0 1.2 0 8.4* 3.2 0.1 0.1 0.6 C x M x K 1, 8 0 0.8 0.1 1.1 0.5 0.3 2.9 0.3 0.1 0.9 0.1 0.6 F. occidentalis adult males C 1, 8 n/a 0.8 1.5 n/a 0.1 0.3 1.2 3.1 1.2 8.9* n/a 2 M 1, 2 n/a 0.8 0.8 n/a 0.1 0.6 0 1 8.2 0.5 n/a 0 C x M 1, 8 n/a 0 0 n/a 0.4 0.3 0 0.2 1.2 0 n/a 3.5 K 1, 4 n/a 1.8 0.2 n/a 0.1 0.1 0.8 2.8 0 0.1 n/a 0.1 C x K 1, 8 n/ a 0 0.2 n/a 0.6 0.9 2.9 1.2 2.7 1.4 n/a 0.2 M x K 1, 4 n/a 0 0.1 n/a 0 1.6 7.4* 0.1 0 0.1 n/a 0 C x M x K 1, 8 n/a 0.3 1.9 n/a 0.1 2.2 0.7 0.1 0.9 0.5 n/a 0.7

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130 Table 3 6. Continued. ANOVA treatment effect d.f. F value 1 May 4 May 8 May 11 May 16 May 18 May 22 May 25 May 30 May 1 Jun 5 Jun 7 Jun Thrips larvae C 1, 8 0.4 1 n/a 7.1* 0.5 0.6 1.2 0.2 4.2 0.7 0.9 4.7 M 1, 2 0.6 2.6 n/a 0 0.2 0.3 0.4 4 0.7 0.1 2.8 0.1 C x M 1, 8 0.9 2.6 n/a 3.7 2.4 5.7* 0.7 1 2.4 3.4 1.3 0 K 1, 4 0.8 1.7 n/a 7.7* 0 .9 5.2 0.4 2.9 1.3 0.4 0.1 0.6 C x K 1, 8 0.7 0.4 n/a 0.1 0.1 0 1 1.3 0.1 3.6 1.1 0.2 M x K 1, 4 1.1 0.1 n/a 0.1 0.1 0.4 0.4 0.9 0.3 0.1 0 0.1 C x M x K 1, 8 0.7 3.5 n/a 1 5.6* 0.6 0.1 0.1 0.6 0 1.7 0.6 a C indicates effect of companion plants, M indica tes mulch effects, K indicates kaolin clay effects. *, P < 0.05; **, P < 0.01; ***, P < 0.001

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131 Table 3 7. ANOVA values for the effects of mulch, kaolin, and the interaction of mulch and kaolin on thrips and O. insidiosus on B. alba in the experiment con ducted in Gadsden county, Florida in 2011. ANOVA Treatment effect d.f. F value 19 April 26 April 29 April 3 May 5 May 10 May 12 May 17 May 19 May 24 May 26 May 31 May 2 June 7 June F. bispinosa adult females M a 1,2 b . 0.4 0.8 1.4 0.4 0.1 0. 0 6.0 1.1 1.5 2.5 K 1,4 . 0.0 0.0 0.1 3.5 0.1 0.8 2.7 1.1 0.4 0.9 M*K 1,4 . 0.1 0.8 0.7 0.4 2.5 0.0 2.7 0.0 0.4 4.8 F. bispinosa adult males M 1,2 . 0.3 1.0 1 . . . . K 1,4 . 3.4 4.0 1 . . . . M*K 1,4 . 0.6 1.0 1 . . . . F. tritici adult females M 1,2 0.9 0.0 0.3 2.2 0.5 0.0 1.1 0.3 0.0 0.0 2.4 16.9* K 1,4 0.8 0.0 0.6 0.3 0.0 1.0 0.4 0.1 0.2 1.5 0.3 1.0 M*K 1,4 0.8 0.1 0.9 1.6 4.0 0.0 4.4 5.2 0.0 1.9 0.0 9.5* F. tritici adu lt males M 1,2 0.4 0.2 0.5 0.8 1.1 0.6 0.2 0.4 0.5 0.2 0.0 0.2 3.4 4.4 K 1,4 0.1 0.0 1.2 4.4 1.5 4.9 1.1 2.2 0.8 0.6 0.7 5.4 1.2 3.4 M*K 1,4 0.0 0.3 0.0 0.0 0.4 0.0 1.2 2.6 0.9 0.9 1.0 1.3 1.3 2.9 F. occidentalis adult females M 1,2 2.1 1.6 0.6 0 .1 2.7 0.1 0.1 1.5 0.6 0.2 0.2 1.0 0.5 0.5 K 1,4 1.7 3.0 1.3 0.3 2.4 1.5 0.0 0.7 1.3 0.2 0.5 0.3 0.1 0.2 M*K 1,4 2.1 0.0 1.7 0.0 0.0 0.1 3.2 1.5 0.3 0.0 0.1 0.3 1.4 0.0

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132 Table 3 7. Continued. ANOVA Treatment effect d .f. F value 19 April 26 April 29 April 3 May 5 May 10 May 12 May 17 May 19 May 24 May 26 May 31 May 2 June 7 June F. occidentalis adult males M 1,2 1.2 0.4 1.1 0.8 1.4 0.1 0.1 0.2 0.2 1.6 0.5 0.3 0.0 0.0 K 1,4 1.2 0.0 0.4 0.0 0.4 0.1 0.1 1.8 2.0 0 .8 0.5 0.0 0.0 0.0 M*K 1,4 1.2 6.8 0.0 0.0 0.4 0.1 7.1 0.2 0.2 0.8 0.5 0.0 2.0 0.3 O. insidiosus adults and nymphs M 1,2 0.8 0.0 0.1 1.3 0.2 0.4 0.1 2.4 4.8 0.4 0.5 0.0 0.1 3.0 K 1,4 0.8 2.8 2.3 0.3 0.5 7.7* 1.3 0.2 0.8 2.3 0.7 1.1 0.1 0.3 M*K 1,4 0.8 0.0 0.1 0.3 0.0 8.8* 1.7 0.2 0.1 0.5 0.0 1.8 0.6 0.3 Thrips larvae M 1,2 1.7 0.5 0.0 0.5 1.0 0.0 1.1 2.5 0.8 5.0 0.7 0.1 5.5 K 1,4 1.7 0.0 0.0 1.3 1.0 1.3 3.3 2.5 0.0 0.0 0.0 0.1 1.5 M*K 1,4 1.7 0.3 1.2 0.5 1.0 0.8 0.4 2.5 0.8 0.0 0.2 0. 4 0.4 a M indicates the effect of the mulch treatments, K is the effect of kaolin treatments and M*K indicates the interaction effect. b indicates numbers were not sufficient for analysis.

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133 Table 3 8. ANOVA values for the effects of mu lch, kaolin, and the interaction of mulch and kaolin on thrips adults and larvae and O. insidiosus adults and nymphs on B. alba in the experiment conducted in 2012. ANOVA Treatment effect d.f. F value 1 May 4 May 8 May 11 May 16 May 18 May 22 May 25 May 30 May 1 June 5 June 7 June F. bispinosa adult females M a 1,2 1.1 14.0 1.9 0.8 2.1 0.1 2.7 0.0 1.6 0.0 0.1 0.0 K 1,4 1.0 0.5 0.1 0.3 0.6 0.2 0.9 0.0 1.3 0.3 1.5 0.7 M*K 1,4 1.7 6.5 1.0 4.8 1.0 0.3 10.6* 0.0 1.0 0.2 0.1 0.0 F. bispinosa adul t males M 1,2 6.0 10.6 0.2 1.9 1.6 0.2 0.0 0.0 1.0 3.5 3.1 3.1 K 1,4 1.5 1.1 0.4 0.5 1.0 0.1 0.1 0.1 1.3 0.0 2.4 0.3 M*K 1,4 0.2 1.8 0.0 1.2 5.7 0.0 0.4 3.0 0.6 1.3 0.3 3.1 F. tritici adult females M 1,2 0.0 11.8 3.3 0.4 0.1 0.2 0.2 0.1 0.1 0.8 0. 1 b K 1,4 0.1 0.1 1.1 1.4 0.5 0.6 0.5 0.0 0.8 0.0 0.6 M*K 1,4 2.2 7.6* 0.3 0.2 0.3 0.1 2.5 0.0 0.1 0.2 2.1 F. tritici adult males M 1,2 13.6 0.3 1.8 1.9 0.2 0.1 0.0 0.8 0.9 0.1 1.5 0.2 K 1,4 0.0 1.4 1.4 4.9 0.2 0.7 0.5 0.8 0.0 0.2 1.2 2.0 M *K 1,4 6.2 6.7 0.3 3.0 1.1 0.2 0.8 0.4 1.8 0.2 0.3 1.1 F. occidentalis adult females M 1,2 0.2 0.0 0.1 1.3 1.8 . . . K 1,4 0.0 0.1 0.1 1.3 0.0 . . . M*K 1,4 1.2 0.0 1.1 2.1 0.0 . . .

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134 Table 3 8. Continu ed. ANOVA Treatment effect d.f. F value 1 May 4 May 8 May 11 May 16 May 18 May 22 May 25 May 30 May 1 June 5 June 7 June F. occidentalis adult males M 1,2 0.9 1.2 0.4 0.1 0.2 0.2 0.7 0.0 2.3 0.0 K 1,4 1.9 3.0 0.4 0.1 0.2 0.5 0.1 0.9 1.3 0 .2 M*K 1,4 0.3 0.1 0.4 4.1 1.6 0.0 0.1 0.9 0.1 0.9 O. insidiosus adults and nymphs M 1,2 0.0 0.1 0.5 0.3 0.1 0.2 2.1 1.9 1.2 0.0 0.5 1.4 K 1,4 0.1 0.4 1.2 0.9 1.4 0.1 0.9 0.3 0.2 1.0 2.1 1.8 M*K 1,4 1.6 0.6 0.0 0.2 0.5 1.3 0.1 0.0 0.8 0.0 2. 1 3.0 Thrips larvae M 1,2 0.7 0.7 1.4 0.3 0.0 0.2 0.4 0.0 1.1 0.0 0.4 K 1,4 0.2 0.0 0.1 0.3 0.4 0.2 0.2 0.0 0.1 0.0 4.0 M*K 1,4 0.2 0.1 0.7 0.3 0.4 0.2 0.1 7.8* 0.2 0.3 0.4 a M indicates the effect of the mulch treatments, K is the effect of kaolin treatments and M*K indicates the interaction effect. b indicates numbers were not sufficient for analysis.

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135 Table 3 9. Mean ( SEM) number and weight per plot of med ium, large, and extra large tomato fruits harvested on 22 and 30 June 2011 an d the ANOVA effects for those variables in the push pull experiment conducted in Gadsden County, Florida. Treatment Mean number (no.) and weight (kgs) per 20 tomato plants (SEM) Unmarketable Medium fruits Large fruits Extra Large kgs N o kgs no kgs no kgs 22 Jun 2011 B a 7 0 10 2 1 0 11 1 2 0 29 5 6 1 B/C 4 1 8 2 1 0 12 3 2 1 32 8 8 2 B/K 6 1 11 1 1 0 16 1 3 0 48 6 11 1 B/C/K 5 1 15 2 2 0 22 3 3 0 48 10 11 3 R 6 2 12 2 1 0 15 2 2 0 45 7 11 2 R/C 8 1 15 0 2 0 22 5 3 1 70 5 16 2 R/K 7 0 10 1 1 0 18 5 3 1 47 22 10 5 R/C/K 7 2 16 2 2 0 25 2 4 0 54 8 12 2 ANOVA F value C (1, 8 d.f.) b 0.2 6.6* 7.3* 6.2* 3.9 4.6 4.2 M (1, 2 d.f.) 2.3 3.4 4. 1 2.4 2.8 3.5 3.6 C x M (1, 8 d.f.) 2.4 2.8 2.4 1.0 0.7 3.2 2.4 K (1, 4 d.f.) 0.1 2.0 2.0 7.1 6.1 0.4 0.2 C x K (1, 8 d.f.) 0.1 3.3 1.8 0.3 0.2 1.5 1.5 M x K (1, 4 d.f.) 0.0 5.1 5.6 1.4 1.3 2.8 3.6 M x C x K (1, 8 d.f.) 0.4 0.4 0.5 0.3 0.1 0.7 0.4

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136 Table 3 9 Continued T reatment Mean number (no.) and weight (kgs) per 20 tomato plants (SEM) Unmarketable Medium fruits Large fruits Extra Large fruits kgs No kgs no kgs no kgs 30 Jun 2011 B 4 1 27 3 3 0 14 3 2 0 4 1 1 0 B/C 4 1 28 7 3 1 9 2 1 0 2 1 0 0 B/K 4 0 22 7 2 1 9 4 1 1 4 1 1 0 B/C/K 5 1 33 3 4 0 15 3 2 0 4 2 1 0 R 5 0 24 6 3 1 20 4 3 1 10 3 2 1 R/C 4 0 27 3 3 0 24 1 4 0 14 2 3 0 R/K 5 1 29 2 4 1 15 2 2 0 14 6 3 1 R/C/K 4 0 30 8 3 1 27 6 4 1 11 2 2 0 ANOVA F value C (1, 8 d.f.) 1.2 1.2 0.2 5.9* 5.2* 0.1 0.0 M (1, 2 d.f.) 0.0 0.0 0.2 10.9 13.7 24.0* 25.6* C x M (1, 8 d.f.) 0.9 0.3 1.0 4.6 3.2 0.0 0.0 K (1, 4 d.f.) 0.1 0 .4 0.9 0.0 0.1 0.3 0.1 C x K (1, 8 d.f.) 0.0 0.4 0.0 7.3* 5.3* 0.7 0.7 M x K (1, 4 d.f.) 0.1 0.3 0.6 0.3 0.6 0.1 0.4 M x C x K (1, 8 d.f.) 0.2 0.6 1.4 0.4 0.5 1.0 1.2

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137 Table 3 9 Continued Treatment Mean number (no.) and weight (kgs) per 20 t omato plants (SEM) Unmarketable Medium fruits Large fruits Extra Large fruits kgs No kgs no kgs no kgs Season Total 22 June 2011 and 30 June 2011 B 11 1 36 3 4 1 25 3 4 0 31 6 7 1 B/C 9 2 36 7 4 1 20 5 3 1 34 9 8 2 B/K 11 1 34 7 4 1 25 3 4 1 52 6 12 1 B/C/K 10 1 48 4 5 1 37 5 5 1 53 12 12 3 R 11 2 36 5 4 1 35 4 5 1 55 9 13 2 R/C 12 1 42 4 5 1 46 5 7 1 84 7 19 2 R/K 11 1 39 0 5 1 33 5 5 1 59 28 13 6 R/C/K 11 2 46 6 5 1 52 5 7 1 65 6 14 1 ANOVA F value C (1, 8 d.f.) 0.5 4.8 2.1 13.6** 9.6* 2.7 2.4 M (1, 2 d.f.) 1.5 0.3 1.5 33.1* 29.1* 8.5 8.4 C x M (1, 8 d.f.) 1.2 0.0 0.3 5.3* 3.3 1.8 1.4 K (1, 4 d.f.) 0.1 1.7 2.3 4.4 3.6 0.6 0.3 C x K (1, 8 d.f.) 0.1 1.9 0.4 5.6* 3.5 1.3 1.3 M x K (1, 4 d.f.) 0.1 0.1 0.0 1.7 2.1 2.9 3.8 M x C x K (1, 8 d.f.) 0.4 1.2 2.3 0.8 0.6 0.9 0.6 a B indicates black mulch, K indicates kaolin, R indicates reflective mulch, C indicates companion plants. b C indicates effect of companion plants, M indicates mulch effects, K indicates kaolin clay effects. *, P < 0.05; **, P < 0.01; ***, P < 0.001

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138 Table 3 10. Mean ( SEM) number and weight per 0.00 7 ha plot of medium, large, and extra large tomato frui ts harvested on 19, 26 June, and 12 July 2012 and the respective ANOVA effects in the push pull experiment conducted in Gadsden County, Florida Treatment Mean number (no.) and weight (kgs) per 20 tomato plants (SEM) Unmarketable Medium fruits Large frui ts Extra Large fruits kgs no kgs no kgs no kgs 19 Jun 2012 B a 2 1 3 1 0 0 8 4 1 1 61 11 14 3 B/C 3 1 4 2 0 0 12 4 2 1 62 10 14 2 B/K 3 0 3 2 0 0 11 1 2 0 82 15 19 4 B/C/K 3 0 8 2 1 0 16 4 2 1 83 21 18 5 R 4 2 1 1 0 0 3 1 0 0 49 20 12 5 R/C 2 0 5 1 1 0 9 3 1 0 66 15 15 4 R/K 3 1 3 2 0 0 8 2 1 0 70 22 17 6 R/C/K 3 1 4 3 1 0 13 4 2 1 63 14 15 4 ANOVA F value C (1, 8 d.f.) b 0.4 6.7* 6.5 6.0* 5.0* 0.1 0.0 M (1, 2 d.f.) 0.2 0.7 0.6 2.1 1.5 0.9 0.2 C x M (1, 8 d.f.) 0.1 0.1 0.1 0.1 0.3 0.1 0.0 K (1, 4 d.f.) 0.2 1.2 1.1 3.4 3.6 3.4 3.0 C x K (1, 8 d.f.) 0.3 0.2 0.1 0.0 0.0 0.5 0.7 M x K (1, 4 d.f.) 0.8 0.3 0.3 0.0 0.1 0.6 0.2 M x C x K (1, 8 d.f.) 1.6 2.3 2.5 0.1 0.0 0.6 0.5

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139 Table 3 10 Continued Treatment Mean number (no.) and weight (kgs) per 20 tomato plants (SEM) Unmarketable Medium fruits Large fruits Extra Large fruits kgs no kgs no kgs no kgs 26 Jun 2012 B 10 2 16 4 2 0 52 9 8 1 112 8 23 2 B/C 8 1 38 13 4 2 55 7 9 1 149 12 30 3 B/K 5 0 17 5 2 1 51 8 8 1 155 23 33 6 B/C/K 8 1 28 7 3 1 48 9 9 1 140 14 28 3 R 13 4 19 7 2 1 32 6 5 1 128 12 27 3 R/C 10 1 29 8 3 1 49 9 8 1 129 25 28 6 R/K 9 1 20 9 2 1 36 3 6 0 151 11 32 3 R/C/K 10 1 25 7 3 1 55 5 8 0 145 27 30 6 ANOVA F value C (1, 8 d.f.) 0.1 10.5** 9.3* 7.1* 13.4** 0.1 0.0 M (1, 2 d.f.) 5.5 0.0 0.0 1.3 1.8 0.0 0.0 C x M (1, 8 d.f.) 0.2 1.5 1.3 7.0* 3.8 0.3 0.1 K (1, 4 d.f.) 4.2 0.3 0.3 0.0 0.2 2.1 1.6 C x K (1, 8 d.f.) 2.9 1.0 0.9 0.1 1.5 1.4 1.5 M x K (1, 4 d.f.) 0.1 0.1 0.1 0.8 0.1 0.0 0.0 M x C x K (1, 8 d.f.) 0.0 0.1 0.1 0.3 0.9 0.8 0.6

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140 Table 3 10. Continued. Treatment Mean number (no.) and weight (kgs) per 20 tomato plants (SEM) Unmarketable Medium fruits Large fruits Extra Large fruits kgs no kgs no kgs no kgs 12 Jul 12 B 7 2 31 4 3 1 26 10 4 2 30 14 6 3 B/C 7 1 33 8 4 1 26 7 4 1 28 12 6 2 B/K 7 1 37 10 4 1 46 9 7 1 44 6 9 1 B/C/K 8 1 28 7 3 1 33 13 5 2 38 24 8 5 R 12 2 53 23 6 3 50 20 7 2 52 23 11 5 R/C 10 2 35 12 4 1 32 4 6 1 37 1 6 8 3 R/K 9 1 29 4 3 1 33 5 5 1 49 14 10 3 R/C/K 9 2 29 11 3 1 32 16 5 2 36 23 7 4 ANOVA F value C (1, 8 d.f.) 0.6 0.9 0.8 1.9 1.5 1.7 2.0 M (1, 2 d.f.) 9.0 0.4 0.4 0.3 0.2 0.2 0.2 C x M (1, 8 d.f.) 0.4 0.2 0.3 0.1 0.1 0 .5 0.7 K (1, 4 d.f.) 0.9 1.2 1.0 0.1 0.1 0.6 0.4 C x K (1, 8 d.f.) 0.5 0.0 0.1 0.0 0.0 0.0 0.0 M x K (1, 4 d.f.) 2.6 1.3 1.2 2.0 2.8 1.0 1.2 M x C x K (1, 8 d.f.) 0.2 1.2 1.2 1.7 0.7 0.1 0.0

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141 Table 3 10 Continued Treatment Mean number (no. ) and weight (kgs) per 20 tomato plants (SEM) Unmarketable Medium fruits Large fruits Extra Large fruits kgs no kgs no kgs no kgs Season total June 19, 26, and July 12 2012 B 19 2 50 1 5 0 86 4 13 0 203 5 44 2 B/C 17 1 75 8 8 1 93 6 14 1 239 10 50 2 B/K 16 1 57 9 6 1 108 5 17 1 281 31 61 8 B/C/K 18 2 64 10 7 1 97 13 16 2 261 31 55 7 R 29 4 73 23 8 3 85 24 12 3 229 13 50 4 R/C 23 2 69 3 8 0 89 9 15 1 231 24 51 6 R/K 20 2 52 8 6 1 77 1 13 0 270 28 60 8 R/C/K 21 2 58 6 7 1 99 17 15 2 244 24 51 4 ANOVA F value C (1, 8 d.f.) 1.0 1.3 1.4 0.8 2.2 0.0 0.2 M (1, 2 d.f.) 15.4 0.1 0.1 0.6 1.1 0.0 0.0 C x M (1, 8 d.f.) 0.8 1.0 1.2 1.3 2.1 0. 4 0.2 K (1, 4 d.f.) 4.4 1.4 1.2 0.4 0.8 5.9 4.2 C x K (1, 8 d.f.) 4.1 0.1 0.0 0.0 0.8 1.7 1.9 M x K (1, 4 d.f.) 2.2 0.8 0.8 0.3 1.1 0.5 0.5 M x C x K (1, 8 d.f.) 0.5 0.9 0.7 1.9 0.1 0.2 0.1 a B indicates plants planted on black mulch, C indicates comp anion plants, K indicates kaolin clay and R indicates plants planted on reflective mulch. b C indicates effect of companion plants, M indicates mulch effects, K indicates kaolin clay effects. *, P < 0.05; **, P < 0.01; ***, P < 0.001;

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142 Figure 3 1. Seasonal variations in the mean ( SEM) number of adult thrips found in tomato flowers in plots with and without companion plantings of B. alba in the experiment conducted in Gadsden county, Florida in 2011.

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143 Figure 3 2. Seasonal variations in the mean ( SEM) number of adult thrips found in tomato flowers in plots with and without companion plantings of B. alba in the experiment conducted in Gadsden county, Florida in 2012.

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144 Figure 3 3 Seasonal variations in the mean ( SEM) number of larval thrips found in tomato flowers in plots with black or reflective mulch, with and without companion plantings of B. alba and with or without kaolin clay in the experiment conducted i n Gadsden county, Florida in 2011.

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145 Figure 3 4 Seasonal variations in the mean ( SEM) number of larval thrips found in tomato flowers in plots with black or reflective mulch, with and without companion plantings of B. alba and with or without kaolin clay in the experiment conducted in Gadsden county, Florida in 2012.

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146 Figure 3 5 Seasonal variations in the mean ( SEM) number of adult thrips found in tomato flowers in plots with and without app lications of kaolin clay in the experiment conducted in Gadsden county, Florida in 2011.

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147 Figure 3 6. Seasonal variations in the mean ( SEM) number of adult thrips found in tomato flowers in plots with and without application s of kaolin clay in the experiment conducted in Gadsden county, Florida in 2012.

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148 Figure 3 7. Seasonal variations in the mean ( SEM) number of adult thrips found in tomato flowers in plots with ultraviolet reflective or black mulch in the experiment conducted in Gadsden county, Florida in 2011.

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149 Figure 3 8. Seasonal variations in the mean ( SEM) number of adult thrips found in tomato flowers in plots with ultraviolet reflective or black mulch in th e experiment conducted in Gadsden county, Florida in 2012

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150 CHAPTER 4 AN EVALUATION OF A PUSH PULL METHOD TO MANAGE TOMATO SPOTTED WILT VIRUS ON TOMATOES IN NORTH FLORIDA. Introduction In Florida, the western flower thrips ( Frankliniella occidentalis Pergand e) is an invasive species of thrips which injures leaves, fruits and flowers of multiple vegetable crops (Childers 1997) and vectors Tomato spotted wilt virus (OEPP/EPPO 2004) The loss to farmers from Tomato spotted wilt is estimated at $1 billio n annuall y (Goldbach and Peters 1994). In the past and present, farmers have dealt with thrips and other pests using multiple applications of broad spectrum pesticides. The use of broad spectrum insecticides does not always alleviate the problem and instead interfe res with the natural control of thrips by the minute pirate bug ( Orius insidiosus ) causing an increase in the numbers of F. occidentalis (Funderburk et al. 2000). Additionally, F. occidentalis has the propensity to quickly develop resistance to many cl asse s of pesticides (Gao et al. 2012). Several technologies have been developed which circumvent the issues associated with pesticide use while still decreasing pest populations, reducing disease incidence, and increasing yield. These technologies include, but are not limited to: spinosads and oth er new insecticides (Funderburk 2009); ultraviolet reflective mulc h technologies (Stavisky et al. 2002, Reitz et al. 2003); the use of companion plants (Kasina et al. 2006, Lopez and Shepard 2007); particle films su ch as kaolin clay (Glenn et al. 1999, Spiers et al. 2004 ); and biocontrol using natural enemies, such as O. insidiosus (Funderburk et al. 2000). A recently developed technology, called the push pull or stimulo deterrent method, combines both repellant plants and attractive plants in a field to repel pest insects from the crop and attract them to a non crop plant on which t hey are

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151 controlled (Khan et al. 2001). This method was effective in reducing damage to maize plants from stemborers in Kenya and may be pro mising for use with other crops and pests. The current study evaluates a new push pull methodology to reduce thrip s numbers and the incidence of T omato spotted wilt on tomatoes. T his method combines ultraviolet reflective mulch (push), kaolin clay sprays ( push) and companion plants (pull) to deter thrips and attract natural predators. Materials and M ethods Experiments were conducted in North Florida in the spring of 2011 and Solanum lycopersicum ) and companion plants of Spani sh needles ( Bidens alba ). Six week old tomato plants and Spanish needle plants were transplanted in late March each year. The plants were produced on raised beds 10 cm in height and 91.4 cm in width with beds spaced 1.83 m and treated before mulch applica tion with Dual Magnum (Syngenta Crop Protection LLC, Greensboro, NC 27419) at 1.2 kg active ingredient per ha for weed control. A trickle tube placed 15 cm off center under the mulch was used to irrigate based on plant needs. Plots were fertilized with 20 4, 29, and 170 kg/ha of N, P, and K, respectively. Pesticides to control other pests such as armyworms were applied on an as needed basis. A randomized complete block split split plot design was used. Whole plot treatments consisted of ultraviolet reflecti ve mulch and black polyethylene mulch (Berry Plastics Corp., Evansville, IN), subplot treatments consisted of Surround WP Kaolin clay (Engelhard Corp., Iselin, NJ) applications and a control, and

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152 sub sub plot treatments consisted of companion plantings of Spanish needles and a control. Kaolin clay was applied two times per week as a spray at a rate of 14 kg per ha. There were three replicates in this experiment with a total of 80 tomato plants per sub sub plot. Each plant in each plot was examined weekly for visual symptoms of Tospovirus infection. Leaf samples were taken from any plant displaying visual symptoms. Infection was verified by testing leaf samples with ImmunoStrips (Agdia, Elkhart, IN). Plants showing no visual symptoms were tested as negativ e controls. Proportions of Tomato spotted wilt were transformed with arcsine square root transformations to improve homogeneity of variance before analyses were conducted. Differences in the cumulative incidence of Tomato spotted wilt between treatments we re analyzed over date with ANOVA using the GLIMMIX procedure (SAS Institute 2008). Results and D iscussion In 2011, the mean seasonal incidence ( + SEM) of Tomato spotted wilt per plot was 5.2 1.0%. In the 2011 season the most common thrips found on the toma to plants was F. tritici with F. occidentalis being the second most numerous thrips and F. bispinosa occurring rarely. In 2012, by contrast, the mean seasonal incidence ( + SEM) of Tomato spotted wilt per plot was much lower, at 1.1 0.3%. During 2012 the mo st common thrips species found was F. bispinosa followed by F. tritici, with F. occidentalis occurring very rarely. The 2012 season followed a very mild and warm winter which may have allowed F. bispinosa to survive and out compete F.

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153 occidentalis which r esulted in lower incidence of Tomato spotted wilt in our experimental plots. The results of the ANOVAs for the 2011 and 2012 experiments are shown in Tables 4 1 and 4 2, respectively. Companion plants had a significant effect on the cumulative incidence of Tomato spotted wilt on the final two dates. The presence of companion plantings significantly reduced the seasonal incidence of Tomato spotted wilt in 2011, and while not significant, such plantings also reduced Tomato spotted wilt incidence in 2012 (Fig. 4 1). The lack of significance in 2012 was likely due to the low disease pressure during that season. Overall, these results have practical significance to growers wishing to reduce incidence of disease in their fields. The reasons for this reduction may be twofold: the first is that thrips were attracted to the companion plant reducing the numbers of thrips feeding and ovipositing on the tomatoes. The second possible explanation is that the companion plant attracted natural predators of thrips to the fie ld, thereby increasing predation and decreasing the number of thrips. Previous studies have found support for the second explanation with the use of intercrops to attract pre dators of thrips (Kasina et al. 2006, Lopez and Shepard 2007, Frantz and Mellinger 200 9, Nyasani et al. 2012). The use of ultraviolet reflective mulch reduced incidence of Tomato spotted wilt in the fields in both seasons, with significant reductions occurring on the fourth and fifth dates in 2011 (Fig 4 2.). Ultraviolet reflective mulc h disrupts the ability of thrips to find their hosts resulting in a reduction of thrips alighting on the plants, and a reduction in the spread of disease to these plants. Our results

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154 are in agreement with previous studies, which found significant reduction s in the incidence of Tomato spotted wilt on ultraviolet reflective mulch compared to black mulch (Greenough et al. 1990, Reitz et al. 2003). Applications of the kaolin clay particle film also resulted in lower incidence of Tomato spotted wilt in the tomat oes. This effect, while not statistically significant, was observed in both years of the experiment (Fig. 4 3). Kaolin clay forms a protective barrier on the plant which reduces heat stress and is deterrent to thrips and other insects. Kaolin clay also det ers thrips from onions (Larentzaki et al. 2008) and blueberries (Spiers et al. 2004) and significantly decreased incidence of disease in another study (Reitz et al. 2008). It may be that the thrips cannot grip plants through the clay, are deterred from fe eding by the texture of the clay, or may be visually deterred from the plants by increased ultraviolet reflection resulting from the white layer of film. The results of our study provide evidence to support the use of ultraviolet reflective mulch, kaolin clay, and Spanish needle companion plants either alone or in various combinations to reduce the numbers of thrips and the incidence of Tomato spotted wilt on tomatoes. Additionally, these methods can be combined with pesticides and other cultural control m ethods to increase the efficacy of an integrated pest management program.

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155 Table 4 1. ANOVA values for the effects of companion pl ants, kaolin clay, mulch types, and their interactions on the incidence of Tomato spott ed wilt in tomatoes in the experiment conducted in Gadsden County, Florida in 2011. ANOVA treatment effect d.f. F value, p value 4 May 11 11 May 11 18 May 11 25 May 11 3 Jun 11 10 Jun 11 17 Jun 11 Companion plant 1, 8 0.05, 0.83 1.84, 0.21 0.79, 0.41 1.13, 0.32 3.46, 0.10 5.96, 0.04 6.83, 0.03 Mulch 1, 2 1.67, 0.33 12.25, 0.07 16, 0.06 32.38, 0.03 16.89, 0.05 13.32, 0.07 6.44, 0.13 Companion plant*Mulch 1, 8 0.05, 0.83 0.32, 0.59 0, 0.99 0.13, 0.73 0.13, 0.73 0.15, 0.71 0.01, 0.91 Kaolin 1, 4 0.95, 0.38 0.8, 0.42 0.74, 0.44 0.57, 0.49 0.62, 0.47 0.69, 0.45 0.35, 0.58 Companion plant*Kaolin 1, 8 0.29, 0.61 0.05, 0.82 0.28, 0.61 0.2, 0.67 0.29, 0.61 0.19, 0.67 1.15, 0.32 Mulch*Kaolin 1, 4 0.29, 0.62 0.01, 0.93 0.24, 0.65 0.1, 0.77 2, 0.23 1.67, 0.27 1, 0.37 Companion plant*Mulch*Kaolin 1, 8 0.29, 0.61 0.32, 0.59 0.14, 0.72 0.18, 0.68 0.17, 0.69 1, 0.35 1.07, 0.33

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156 Table 4 2. ANOVA values for the effects of companion plants, kaolin clay, mulch types, and their interactions on the incidence of Tomato spotted wilt in tomatoes in the experiment conducted in Gadsden County, Florida in 2012. ANOVA treatment effect d.f. F value p value 11 May 12 18 May 12 25 May 12 28 May 12 8 Jun 12 Companion plant 1, 8 1, 0.35 0.07, 0.80 0.17, 0.69 0.89, 0. 38 2.39, 0.16 Mulch 1, 2 1, 0.43 1.08, 0.41 0.75, 0.48 1.04, 0.41 0.53, 0.54 Companion plant*Mulch 1, 8 1, 0.35 0.97, 0.35 4.12, 0.08 2.93, 0.13 2.61, 0.15 Kaolin 1, 4 1, 0.37 3.6, 0.13 1.13, 0.35 0.49, 0.53 2.21, 0.21 Companion plant*Kaolin 1, 8 1, 0. 35 0.07, 0.80 1.5, 0.26 0.89, 0.37 1.11, 0.32 Mulch*Kaolin 1, 4 1, 0.37 1.08, 0.36 0.13, 0.74 0.01, 0.91 0.11, 0.75 Companion plant*Mulch*Kaolin 1, 8 1, 0.35 0.97, 0.35 0.17, 0.69 0.02, 0.88 1.63, 0.24

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157 Figure 4 1. Mean percent incidence of Tom ato spotted w ilt in tomato plots in 2011 and 2012 in plots with and without companion plants in the experime nt conducted in Gadsden county, Florida. 0 1 2 3 4 5 6 7 8 9 4 May 11 11 May 11 18 May 11 25 May 11 3 Jun 11 10 Jun 11 17 Jun 11 Mean ( SEM) percent incidence Date 2011 With companion plant Without companion plant 0 0.5 1 1.5 2 2.5 11 May 12 18 May 12 25 May 12 28 May 12 8 Jun 12 Mean ( SEM) percent incidence Date 2012 With companion plants Without companion plants

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158 Figure 4 2. Mean percent incidence of Tomato spotted w ilt in toma to plots in 2011 and 2012 fo r each mul ch type 0 1 2 3 4 5 6 7 8 9 10 4 May 11 11 May 11 18 May 11 25 May 11 3 Jun 11 10 Jun 11 17 Jun 11 Mean ( SEM) percent incidence Date 2011 Black mulch Reflective mulch 0 0.5 1 1.5 2 2.5 11 May 12 18 May 12 25 May 12 28 May 12 8 Jun 12 Mean ( SEM) percent incidence Date 2012 Black mulch Reflective mulch

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159 Figure 4 3. Mean percent incidence of Tomato spotted wilt in t omato plots in 2011 and 2012 in plots that did or did not receive applications of kaolin clay. 0 1 2 3 4 5 6 7 8 Mean ( SEM) percent incidence Date 2011 Kaolin clay No Kaolin clay 0 0.5 1 1.5 2 2.5 11 May 12 18 May 12 25 May 12 28 May 12 8 Jun 12 Mean ( SEM) percent incidence Date 2012 Kaolin clay No Kaolin clay

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160 CHAPTER 5 CONCLUSIONS AND FUTURE DIRECTIONS Recent outbreaks of F. occi dentalis which are resistant to numerous classes of insecticides have led to outbreaks or Tomato spotted wilt and other Tospoviruses in Florida. In response to this crisis, and in response to a changing consumer climate with higher demands of organic produ ce and sustainability, a novel push pull method of thrips and Tospovirus management was evaluated. This method was tested on tomatoes and peppers using two different companion plants. The three components involved in this method displayed separate and in teractive effects on thrips populations, disease, and yield. Kaolin provides the greatest level of thrips control in peppers, and ultraviol et reflective mulch also reduced thrips numbers in peppers However, both of these components may interfere with natu ral predation and kaolin should be stopped mid season to allow predators to return to fields to suppress thrips naturally. Both of these components lead to increased yield. Sunflower and B. alba companion plants increased thrips numbers early in the season with reductions occurring later. Unfortunately sunflowers did not increase yield whereas B. alba did increase yield of tomatoes. Ultraviolet reflective mulch also increased yield of tomatoes while the effects of kaolin on tomato yield were inconsistent. Ultraviolet reflective mulch and B. alba companion plants both significantly reduce Tomato spotted wilt incidence in tomatoes. Kaolin also decreases this incidence, though not significantly.

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161 Consistent effects suggest the ultraviolet reflective mulch and B. alba companion plants reduce thrips numbers, increase yield and reduce disease incidence significantly. Kaolin reduces thrips consistently but does not have consistent or predictable effects on disease or yield. While thrips and disease reduction are de sirable, future investigations into this method need to determine the economics of the various combinations of this system. Ideally these economic analyses would evaluate the costs of these components compared with the cost of buying and using pesticides a nd the resulting revenue from yield from each of those alternatives. Growers would greatly benefit from this information and would be better able to make a beneficial choice. Future studies should also test other species of companion plants as possibiliti es for the two crops. In addition to other species of companion plants, different landscape designs need to be evaluated to determine the appropriation of land needed for these plants to be effective. Whether the plants would be more effective in between r ows, along roads and ditches or directly in between plants is useful information that is lacking. The effects on these companion plants on other pest species, natural enemies and pollinators should also be researched to determine its compatibility with oth er ecosystem services and vertically integrated pest management systems. Additionally, evaluating these components side by side with traditional pest management strategies in years and areas with different disease pressure would be highly informative. This method needs also to be evaluated while operating at larger scales such as on larger commercial farms. Results from

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162 investigations such as these could provide valuable information to be presented to extension agents and directly to growers. Information al one is helpful, however, an even more crucial component is education and extension. Persuading growers to change their own pest management programs to such a new method will be difficult, to say the least. Partnerships with extension agents, influential gr owers and crop consultants will be key to pushing the implementation of this new method on Florida farms. Although it may be difficult, this method is flexible to many crop, pest, and climate situations in addition to being organic and sustainable. Growers can experiment with these components on their own farms and apply pesticides when needed, if the method does not appear to be effective for their situation. Although there are still facets of this method to be investigated, and although the implementatio n of this method on commercial farms will be difficult, it will be worth it. The reduction in chemicals entering our food system and waterways, the reduction in pesticide resistance, and the reduction in environmental degradation make the challenge well wo rth it. I hope the results of this thesis will encourage growers to try these methods on their farms and will encourage more research into alternatives to pesticides for controlling insect pests in agricultural systems in Florida

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178 BIOGRAPHICAL SKETCH Kara Tyler Lakes, Flo rida. She obtained her Bachelor of the Arts from New College of Florida in 2009 where she studied behavior of the Florida Manatee. She married her husband, Paul Julian II, an environmental scientist in 2009. In graduate school she studied Integrated Pest Management and all aspects of Thysanopt era. She will obtain her Master of Science in 2013.