Title: Florida plant disease management guide
Full Citation
Permanent Link: http://ufdc.ufl.edu/UF00053871/00008
 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: VID00008
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:

PG04400 ( PDF )

Full Text

IFAS Extension

2006 Florida Plant Disease Management Guide: Celery1

Richard Raid and Tom Kucharek 2

Specific Common Diseases

Bacterial Blight and Brown Stem
(Pseudomonas cichorii)

Symptoms: While bacterial blight often occurs in
the seedbeds, it occasionally causes extensive
damage in the field. Bacterial blight leaf lesions may
be easily confused with those caused by Cercospora,
but characteristically bacterial blight lesions are
smaller, more angular (frequently being delineated by
the veins), have a deeper reddish-brown color, and
have a water-soaked appearance. Additionally,
chlorosis does not develop as rapidly with bacterial
blight and lesion margins are much more defined than
those incited by Cercospora, the cause of early blight.
Brown stem is characterized by elongated, water
soaked lesions on the petiole. The discoloration is
more evident on the inside of the petiole close to the
crown, but streaks may occur anywhere along the
petiole. Vascular bundles appear healthy, yet are
surrounded by diseased pith. On plants cut for whole
stalks, brown stem may render the entire plant
unmarketable, resulting in substantial yield losses
where incidence is heavy. See Plant Pathology Fact
Sheet PP-8.

Cultural Controls: Control of bacterial blight is
difficult. The disease is favored by warm, wet
conditions. In seedbeds, mechanical transmission
can be minimized by trimming when foliage is dry.
Do not apply foliar nitrogen during warm, wet
periods which are favorable for blight and avoid
over-fertilization with soil-applied nitrogen.
Minimizing mechanical contact with the plants once
set in the field may also prove helpful. Use seepage
irrigation rather than overhead irrigation.

Chemical Control: Fixed copper sprays remain
the mainstay of chemical management of bacterial
blight. See PPP-6.

Cucumber Mosaic (Cucumber mosaic virus)

Symptoms: Cucumber mosaic virus (CMV)
causes a mosaic and mottling of foliage (light green
and dark green areas intermingled on the leaf). CMV
may also cause stalk pitting. Severe plant stunting
may result from infection.

Cultural Controls: Weeds can harbor the virus
as well as the aphid vector, therefore proper weed
management in and around seedbeds and fields is
essential. The dayflower weeds, Commelina spp., are
frequent CMV weed hosts in Florida.

1. This document is PDMG-V3-36, one of a series of the Department of Plant Pathology, 2006 Florida Plant Disease Management Guide, Florida Cooperative
Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Date reviewed: January 2006. Please visit the EDIS Web site at
2. R. Raid, professor, Plant Pathology Department, Everglades Research and Education Center--Belle Glade, FL; T.A. Kucharek, professor, Plant Pathology
Department, Florida Cooperative Extension Service, Insitute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611.

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

2006 Florida Plant Disease Management Guide: Celery 2

Damping-off (Rhizoctonia spp., Pythium
spp., Fusarium spp., and Sclerotinia spp.)

Symptoms: Seedlings may damp-off at random
or in rapidly enlarging circular areas in the seedbeds.
In the latter case, lesions may be observed well up the
petioles as well as at the soil line. Entire plantings
may be lost unless adequate control measures are

Cultural Controls: Damping-off is favored by
excessive soil moisture. Avoid over-saturation of
seedbeds and do not transplant obviously diseased
plants to the field. Transplants should be grown in
sterilized soil or fumigated soil. Use raised beds.

Early Blight (Cercospora apii)

Symptoms: Early blight is the most serious
fungal disease of celery in Florida. It starts as small
circular spots on the leaves or petioles. These rapidly
enlarge and may encompass the entire leaflet and
even the stalk. Petiole lesions are more elongated
than circular due to the heavy veination. Under
humid conditions, lesions may take on a gray
appearance due to the presence of spores on the leaf
surface. Large chlorotic areas often surround the
circular lesions.

Cultural Controls: Celery varieties with
demonstrated resistance to early blight should be
planted, particularly during periods that are most
favorable (warm and humid). Early Belle and June
Belle are two varieties with good early blight
resistance. Florida 683 and 2-14 are most susceptible
and should not be planted except for the cooler
months. See Plant Pathology Fact Sheet PP-8.

Chemical Control: Fungicides should be applied
at the first sign of disease incidence. Broad spectrum
protectants (chlorothalonil) should be applied in
sufficient volume to obtain thorough coverage. Sterol
inhibitor and strobilurin fungicides, exhibiting some
systemic properties, should be applied in a program
with a broad-spectrum protectant to minimize the risk
of fungicide insensitivity developing. See PPP-6.

Late Blight (Septoria apiicola)

Symptoms: Late blight is typically of minor
importance but outbreaks do occasionally occur. The
chief diagnostic feature of late blight is the
occurrence of small black fungal fruiting bodies
(pycnidia) near the center of the circular brown
lesions. These black specks may be observed with the
naked eye or under low magnification. See Plant
Pathology Fact Sheet PP-8.

Cultural Controls: Late blight spores are
rain-splash disseminated. Therefore, the disease is
promoted by extended rainy periods, particularly
during cool to moderate temperatures. The pathogen
is capable of surviving on seed for periods of up to 2
years, but no longer. Therefore, the most economical
control is to plant seed that is three-years-old or
older. Movement of equipment and personnel
through dew-laden fields infested with late blight
should also be minimized as this also spreads the

Chemical Control: The same fungicides used to
control early blight may be used to manage late
blight. See PPP-6.

Pink Rot (Sclerotinia sclerotiorum)

Symptoms: This fungal disease is characterized
by a sudden wilting and collapse of the plants in the
field. A soft watery decay of tissues near the soil line
usually is present. Rotting tissues often take on a
pinkish cast and black fungal resting bodies
(sclerotia) develop within the cottony white
mycelium covering the rotting mass. Sclerotia are
variable in size from 1/8 to 1/2 inch and are usually
somewhat irregular in shape.

Cultural Controls: Where possible, flooding of
celery fields during the summertime in Florida is
extremely effective in controlling this disease. Flood
the soil completely, partially, or intermittently for a
6-week period. If flooding is not possible, turn the
soil 6-8 inches deep to bury the sclerotia and old plant
debris. Crop rotation with a crop not susceptible to
the pathogen (i.e. corn) may be useful, however,
sclerotia may survive for years in the soil.

2006 Florida Plant Disease Management Guide: Celery 3

Chemical Control: Fungicides should be first
applied at the first sign of disease. Broad spectrum
protectants (chlorothalonil) should be applied in
sufficient volume to obtain thorough coverage. Sterol
inhibitor and strobilurin fungicides, exhibiting some
systemic properties, should be applied in a program
with a broad spectrum protectant to minimize the risk
of fungicide insensivity development in the fungus.
See PPP-6.

Red Root (Fusarium sp.)

Symptoms: Red to brownish bands on the roots
and death of root tips characterize this disease. Red
root is primarily a seedbed problem but occasionally
severe field problems may arise.

Cultural Controls: Fumigation of seedbeds
usually gives initial control of redroot. Avoid
recontamination of seedbeds by not stepping onto the
bed after fumigation. The judicious use of fertilizer
and water often allows plants to make a nearly
complete recovery.

Rhizoctonia Stalk Rot (Rhizoctonia solani)

Symptoms: Stalk rot is characterized by sunken,
orange to brown brick-red lesions on the stalks,
particularly at the base of plants. Severe infection
may necessitate extreme trimming of affected
petioles from infected plants.

Cultural Controls: Transplants should be raised
in fumigated beds to provide disease-free planting
material. Care should be taken not to set transplants
excessively deep, as this increases exposure of the
susceptible lower petiole and crown area to the fungal
pathogen. Use raised beds in field.

Chemical Control: Fungicides directed toward
the base of the plant and adjacent soil may aid in the
control of stalk rot. See PPP-6.

Celery Mosaic (Celery mosaic virus;
formerly Western Celery Mosaic Virus)

Symptoms: This virus causes mosaic or mottling
of foliage, similar to cucumber mosaic virus. Severe
leaf distortion and twisting as well as general plant
stunting are additional symptoms of this viral disease.
Aphids and leaf miners are common vectors of this

virus and may they may transmit the virus to celery
after feeding on infected volunteer celery or other
umbelliferous weed hosts.

Cultural Controls: Eradicate potential weed
reservoirs around seedbeds and celery fields.
Mockinishopweed is susceptible as are other
umbelliferous weeds. Have a celery-free period
during the year.

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