Title: Florida plant disease management guide
Full Citation
Permanent Link: http://ufdc.ufl.edu/UF00053871/00006
 Material Information
Title: Florida plant disease management guide
Alternate Title: Ornamentals and turf
Fruit and vegetables
General plant pathology, field crops and pasture grasses, fungicides, adjuvants and application techniques
Physical Description: v. : ; 28 cm.
Language: English
Creator: University of Florida -- Dept. of Plant Pathology
Florida Cooperative Extension Service
Publisher: The Extension
Place of Publication: Gainesville Fla
Frequency: annual
Subject: Plant diseases -- Periodicals -- Florida   ( lcsh )
Pesticides -- Periodicals   ( lcsh )
Statement of Responsibility: Plant Pathology Dept., University of Florida and Institute of Food and Agricultural Sciences, Florida Cooperative Extension, University of Florida.
Numbering Peculiarities: Issued in three volumes: v. 1, General plant pathology, field crops and pasture grasses, fungicides, adjuvants and application techniques; v. 2, Ornamentals and turf; v. 3, Fruit and vegetables.
General Note: Description based on: 1999-2000.
General Note: "SP-52"
 Record Information
Bibliographic ID: UF00053871
Volume ID: VID00006
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: oclc - 44549741
lccn - 00229071
 Related Items
Preceded by: Florida plant disease control guide


This item has the following downloads:

PG04200 ( PDF )

Full Text

IFAS Extension

2007 Florida Plant Disease Management Guide:


Pam Roberts and Tom Kucharek2

Alternaria Leaf Spot (Alternaria

Symptoms: Small circular spots (may appear
water-soaked) develop on leaves and enlarge to 1/2
inch or more across. Concentric rings appear in the
spots as they enlarge, giving a "target spot"
appearance. Fruit is seldom attacked unless plants are
nutrient deficient. The pathogen over-seasons on
infected plant debris and spores are wind-borne and
rain-splash dispersed. See Plant Pathology Fact Sheet

Chemical Controls: See PPP-6.

Angular Leaf Spot (Pseudomonas
syringae pv. lachrymans)

Symptoms: Symptoms occur on the leaves,
stems, and fruit. Spots on the leaves are irregular in
shape, angular, and water-soaked. Free moisture
allows the bacteria to ooze from the spots, which,
upon drying, leave a white residue. These spots of
dead tissue will occasionally drop away from the

healthy tissue leaving irregular holes in the leaves.
Bacterium is seedborne and rain-splash dispersed.
This bacterial disease occurs during cool weather.

Cultural Controls: Use pathogen-free seed.
Rotate land. Avoid handling plants when wet.

Chemical Controls: See PPP-6.

Anthracnose (Colletotrichum

Symptoms: This disease has not been a common
disease in Florida. The disease symptoms first appear
on the foliage as small, yellow, water-spots that
enlarge rapidly and turn brown. The dead tissue dries
and may crack and fall out. On the stems, the lesions
are elongated. On the fruits, dark, circular, sunken
lesions appear, varying in size with the age. During
wet weather the center of the spots often show a
pinkish color due to production of spores.

Cultural Controls: Choose resistant varieties.
Deep plow plant residue and practice crop rotation.

1. This document is PDMG-V3-34, one of a series of the Department of Plant Pathology, 2007 Florida Plant Disease Management Guide, Florida Cooperative
Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Revised December 2005. Reviewed January 2007. Please visit the
EDIS Web site at http://edis.ifas.ufl.edu.
2. Pam Roberts, associate professor, Plant Pathology Department, Southwest Florida REC--Immokalee, FL; Tom Kucharek, professor emeritus, Plant
Pathology Department, Florida Cooperative Extension Service, Insitute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611.
The use of trade names in this publication is solely for the purpose of providing specific information. UF/IFAS does not guarantee or warranty the products
named, and references to them in this publication does not signify our approval to the exclusion of other products of suitable composition.

The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and
other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex,
sexual orientation, marital status, national origin, political opinions or affiliations. U.S. Department of Agriculture, Cooperative Extension Service,
University of Florida, IFAS, Florida A. & M. University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Larry
Arrington, Dean

2007 Florida Plant Disease Management Guide: Cantaloupe 2

Chemical Controls: See PPP-6.

Bacterial Fruit Blotch (Acidovorax
avenae subsp. citrulli)

Symptoms: Angular, water-soaked leaf spots that
are restricted by leaf veins occur in an aggregated
pattern on leaves. Lesions may appear as pin-striping
aside of veins. During dry conditions these spots
become light brown and have a papery thin
consistency. Sunken spots that are slightly
water-soaked, and green occur in fruit. These sunken
spots can be 1" or greater in diameter and may
occur anywhere on the fruit, but they are most
common on the top and sides of the fruit.

Cultural Controls: Purchase seed that are
indexed to be free of bacterium. Purchase transplants
that are disease-free. Use crop rotation with
non-cucurbit crops. Destroy cucurbit weeds and
cucurbit crop volunteers.

Chemical Controls: See PPP-6. Use
copper-containing fungicides if necessary.

Cercospora Leaf Spot (Cercospora

Symptoms: Leaf spots are small (ranging from
1/8"-1/4" in diameter), circular and often are
surrounded by a slight yellow halo. The lesion centers
typically develop a white color. Spores are air-borne
and rain-splash dispersed. Fungus over-seasons on
plant debris and weed hosts

Cultural Controls: Destroy infected plant

Chemical Controls: See PPP-6.

Damping-Off (Pythium spp.,
Fusarium spp., Rhizoctonia spp.)

Symptoms: This disease on seedling cantaloupes
is caused by several soil-inhabiting fungi that are
almost universal in occurrence. These fungi infect
portions of the plant at or below the soil level,
resulting in collapse and death of the seedling.
Conditions unfavorable for rapid emergence of
cantaloupes (cool, wet weather) are usually most

favorable for this disease. Plant in well-tilled soil
where old crop and weed debris has been plowed
down 30 days previously. See Plant Pathology Fact
Sheets PP-1 and PP-53.

Chemical Controls: Plant only fungicide-treated
seed (most seed is purchased pre-treated). See PPP-6.

Downy Mildew (Pseudoperonospora

Symptoms: This disease first appears on the
foliage as pale areas separated by islands of darker
green tissue. These spots develop into an angular,
yellowish lesion. Older lesions become brown and
necrotic. Severely affected leaves may become
chlorotic, brown and shrivel. During moist periods, a
grayish spore mass may be observed on the lower leaf
surface under these spots. Spores are dispersed by
wind. See Plant Pathology Fact Sheet PP-2.

Cultural Controls: Choose resistant varieties.

Chemical Controls: See PPP-6.

Gummy Stem Blight (Didymella
bryoniae/Phoma cucurbitacearum)

Symptoms: On young seedlings, lesions on the
cotyledons and true leaves are round or irregular,
brown, with faint concentric rings. Lesions on the
crown and stem are brown and usually turn white
with age. The causal fungus can often be observed to
reproduce on the crowns or stem lesions and will
produce small black specks (pycnidia) in the plant
tissue. The fungus over-seasons on old plant debris
and can be seedborne. The pathogen is spread by
splashing rain from plant to plant, or be carried long
distances on wind currents. See Plant Pathology Fact
Sheet PP-27.

Cultural Controls: Avoid planting in fields with
residual cucurbit crop debris still present. Purchase
disease-free transplants.

Chemical Controls: Use treated seed. See PPP-6,
for foliar fungicides.

2007 Florida Plant Disease Management Guide: Cantaloupe 3

Powdery Mildew (Erysiphe
spp./Sphaerotheca fulginea)

Symptoms: The fungus affects the leaves and
stems. Symptoms first appear as round whitish spots
on the under side of the older leaves. The spots
increase in number and size and coalesce. These
appear on the upper surface with a white powdery
growth. Severely affected leaves lose their normal
dark color, become pale yellow green, then brown,
and shrivel. The young stems may also be killed.
Fruits of infected vines ripen prematurely, are of poor
quality and often become sunburn. Spores are readily

Cultural Controls: Purchase disease-free

Chemical Controls: See PPP-6.

Viruses (Cucumber mosaic virus,
Papaya ringspot virus, Watermelon
mosaic virus 2, Zucchini Yellow
mosaic virus)

Symptoms: Leaves show varying degrees of
mottling, distortion and stunting. Growth habit may
altered as infected vine tips appear more erect. Fruits
may occasionally be mottled and deformed. These are
the most common viruses in cantaloupe in Florida.
They may also occur naturally on many weed hosts
throughout the state and is moved into cantaloupes by
aphid feeding.

Cultural Controls: Control weeds in and around
plantings. This will aid in virus control. Treating
fields repeatedly for aphid control is not
recommended because of the short time period
needed by aphids to transmit the virus while feeding.
JMS Stylet Oil can be sprayed in a rigorous program
to delay the onset of the epidemic.

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