• TABLE OF CONTENTS
HIDE
 Copyright
 Title Page
 Introduction
 Contents






Group Title: Research report - Bradenton Agricultural Research & Education Center - GC1979-1
Title: Nematodes and their control
CITATION PAGE IMAGE ZOOMABLE PAGE TEXT
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00067718/00001
 Material Information
Title: Nematodes and their control
Series Title: AREC-Bradenton research report
Physical Description: 5 leaves : ; 28 cm.
Language: English
Creator: Overman, A. J ( Amegda J )
Agricultural Research & Education Center (Bradenton, Fla.)
Publisher: Agricultural Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida
Place of Publication: Bradenton Fla
Publication Date: 1979
 Subjects
Subject: Nematoda -- Control -- Florida   ( lcsh )
Nematode diseases of plants -- Control -- Florida   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
bibliography   ( marcgt )
non-fiction   ( marcgt )
 Notes
Bibliography: Includes bibliographical references.
Statement of Responsibility: A.J. Overman.
General Note: Cover title.
Funding: Bradenton AREC research report
 Record Information
Bibliographic ID: UF00067718
Volume ID: VID00001
Source Institution: Marston Science Library, George A. Smathers Libraries, University of Florida
Holding Location: Florida Agricultural Experiment Station, Florida Cooperative Extension Service, Florida Department of Agriculture and Consumer Services, and the Engineering and Industrial Experiment Station; Institute for Food and Agricultural Services (IFAS), University of Florida
Rights Management: All rights reserved, Board of Trustees of the University of Florida
Resource Identifier: oclc - 73173008

Table of Contents
    Copyright
        Copyright
    Title Page
        Title Page
    Introduction
        Introduction
    Contents
        Page 1
        Page 2
        Page 3
        Page 4
        Page 5
Full Text





HISTORIC NOTE


The publications in this collection do
not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
Electronic Data Information Source
(EDIS)

site maintained by the Florida
Cooperative Extension Service.






Copyright 2005, Board of Trustees, University
of Florida




2 00
F30 *--


NEMATODES AND THEIR CONTROL


Agricultural
Institute of


A. J. Overman
Nematologist
Research and Education Center
Food and Agricultural Sciences
University of Florida
Bradenton, Florida


ELIDRARY
OCT 1979

I.F..SUniv. of Florida


AREC-Bradenton Research Report GC1979-1






INTRODUCTION

Nematodes are small rouidworms. They ihhabit the water and the soil-of the
earth, feeding on dead organic matter, living plants and animals.

Plant parasitic nettatodes, with very few exceptions, are microscopic ranging
in size from 1/100 to 1/10 ich loAg ahd smaller than human hair in diameter. One
of the most widely distributed exceptions is the root-knot nematode, Meloidogyne
spp., which begins life as A veiiford, actively mobile larva. However, as the female
matures within the plant hodt tissue, she becomes sedentary and swollen.

Feeding habits differ among the various types of plant parasitic nematodes.
However, on plants, all feeding is a suction process the nematodes puncture the
cell wall of the plant at the feeding site and suck the cell contents into their
bodies.

Of economic importance in Florida's vegetable production, there are two types
of nematodes: 1) ectoparasites which spend their entire life cycle in the soil
water and 2) endoparasites which also live in the soil water but complete their
life cycle inside the tissue of plant roots.

Length of the life cycle determines how rapidly a field infestation may reach
economically damaging levels. Length of the life cycle depends on 1) the nematode
species involved, and 2) the environmental conditions. In Florida soils most nema-
todes are active throughout the year; however, development may be accelerated or
retarded by changes in temperature, moisture and availability of food supply.

Most economically important nematodes are obligate plant parasites. They re-
quire the tissue of living plants for food. In Florida they are seldom deprived of
food long enough to eliminate the population, because fields are clean fallow for
only a few weeks of the year. Some species, such as the spiral nematode found in
sugarcane fields, have been recovered in appreciable numbers after 8 months of
clean fallow.

The egg stages of plant parasites are particularly resistant to environmental
stress. The population decreases, but elimination is difficult to achieve. Recrop-
ping abandoned fields generally results in reestablishing damaging levels of infes-
tations within a few years even when rootknot-infested fields have been in weed
cover for 10 years.












Sources of information for this handout include:

Goodey, J. B., et al. The nematode parasites of plants catalogued under their hosts,
III. 1965. Comm. Agr. Bur., Bucks, England.

Webster, J. M. (ed.). Economic Entomology. 1972. Acad. Press, N.Y.






NEMATODES AND THEIR CONTROL


IDEALLY --

A pest management program is an economically practical
method for producing maximum marketable yields in a pest-
infested environment, and protects the crop from economic
levels of damage caused by:

1. Nematodes
2. Insects
3. Weeds
4. Disease organisms


1. WHAT ARE NEMATODES?

1. Microscopic sized (1/100 to 1/10 inch long)
2. Round worms
3. Aquatic ancestry
4. Feed on:
a. dead organic matter
b. living animals
c. living plants


2. WHERE ARE NEMATODES?

Wherever water, air and food supply are available
in proper proportion:

1. Oceans
2. Fresh water
3. Plants
4. Animals


3. HOW DO NEMATODES SPREAD?

ACTIVE:
1. random
2. due to root attractant

PASSIVE:
1. in soil on machinery
2. in surface water
3. in bulk soil
4. in plants
a. transplants
b. nursery stock
c. corms, bulbs, rhizomes
5. re-used containers
6. people and their tools
7. occasionally, wind







4. WHAT FAVORS NEMATODE SURVIVAL?

IN FLORIDA SOIL:
Conditions favorable for host development


5. WHAT INFLUENCES CROP DAMAGE BY NEMATODES?

1. Pathogenicity level
2. Age of the host crop
3. Crop stress due to:
a. moisture
b. nutrition
c. temperature
4. Associated plant pathogens


6. HOW DO NEMATODES DAMAGE PLANTS?

ENDOPARASITES
1. interfere with pathways by which water and
nutrients move through the plant
2. by wounding the plant, offer easy access to
other pathogens

ECTOPARASITES
1. restrict root elongation
a. reduce volume of soil in which root may
forage for food
2. by wounding the plant, offer easy access to
other pathogens

7. SYMPTOMS OF NEMATODE DAMAGE:

PLANT TOPS:
1. foliage wilt
2. retarded growth
3. nutrient deficiency symptoms
4. necrotic lesions
5. devitalized buds
6. poor response to nutrient applications

ROOT SYSTEM
1. root galls
2. curly tip of roots
3. root rot
4. surface necrosis
5. discolored lesions
6. excessive root branching
7. injured root tips (looks like salt burn)
8. limited root mass







8. WHAT METHODS OF CONTROL ARE AVAILABLE?

1. Quarantine to prevent entry
2. Eradication of the pest
3. Farm hygiene and cultural practices
4. Biological control
5. Ecological control
6. Escape by site selection (field rotation)
7. Physical control
8. Chemical control
9. Fallow
10. Crop rotation
11. Resistant varieties
12. Tolerant varieties





NOTE: A GOOD PEST MANAGEMENT PROGRAM WOULD INCLUDE AS
MANY OF THESE PROCEDURES AS ARE ECONOMICALLY PRACTICAL.



9. WHAT CULTURAL PRACTICES FAVOR CONTROL OF NEMATODES?

1. Destruction of crops after harvest
2. Off-season cultivation
3. Flooding
4. Scheduled crop rotation
A. Effectiveness for root-knot control
depends on:
1. Uniform stand
2. No broadleaf weeds
3. No legumes
4. No old crop volunteers
5. Use of resistant crop varieties
A. Tolerant crop plants grow in nematode-
infested soil, but increase the popula-
tions to a damaging level;
therefore, rotations must contain one
or more non-hosts to protect the suscep-
tible host.


10. HOW TO DETERMINE IF NEMATODE CONTROL WOULD BE PROFITABLE

1. Identify the nematodes associated with the crop
2. Determine population density in rootzone of crop
3. Quantify the types of crop damage
4. Calculate economic loss due to damage
5. Determine the available means of control and degree
of effectiveness, individual and collective methods
6. Determine fixed and variable costs of methods compat-
ible with crop management
7. Compare costs with benefits and derive ratios to deter-
mine profitability of alternative methods
8. Compare the above with the alternative: eliminating
the crop completely and using released resources for
other purposes







11. DISADVANTAGES OF NEMATICIDES:

1. Cost (tomato = 5 to 18% of production cost)
2. Delay in planting (2 to 4 weeks)
3. Non specific
a. kills predators of nematodes & other pests
b. requires waiting period
4. Contacts
a. control is slow
b. crop can be planted at application, endangering the seedlings
c. weed problem may increase
d. sugarcane borers may increase

12. CONTACT NEMATICIDES IN SANDY SOILS

ADVANTAGES:
1. does not require extensive field preparation
2. immediate planting after application
3. residual control

DISADVANTAGES:
1. not fungicidal at agricultural rates
2. leachable to a degree
3. unstable in alkaline media

13. WHICH CHEMICALS CONTROL NEMATODES AND ARE AVAILABLE IN FLORIDA:

T Vorlex
Dowfume MC-2
< Dowfume MC-33
43 Brozone
0 Chloropicrin
U Telone C
DD-Pic or Terr-O-cide 15D or Vidden DC-15
S Terr-O-cide 15
S DD or Vidden D
b Telone
S Dowfume W-85





-5-




14. WHEN AND HOW TO MEASURE NEMATODE POTENTIAL IN THE FIELD

1. Sample at crop maturity
2. Composite soil sample from rootzone of
healthiest plants
3. Composite soil sample from rootzone of
damaged (not dead) plants
4. Samples should contain both roots and
soil which surround the roots
5. Add nothing to the sample
6. Seal in clean plastic bags
7. Mark bags for identifications
8. Keep cool (samples, that is)
9. Deliver immediately to county agent




University of Florida Home Page
© 2004 - 2010 University of Florida George A. Smathers Libraries.
All rights reserved.

Acceptable Use, Copyright, and Disclaimer Statement
Last updated October 10, 2010 - - mvs