Fungicides and Vegetable Disease Control

Fungicides can be a great help in preventing diseases when properly applied to the plant foliage. Since fungicides are preventive, they should be applied before the disease occurs, or as soon as the first symptoms of disease appear. Some vegetable diseases require specific fungi- cides for their control. An outline of diseases of specific vegetables, disease description, suggested cultural and chemical control and comments follows this section.
Fungicides are available primarily as wet- table powders, dry flowables and dusts, but a few are sold as emulsifiable concentrates, flowables and liquids. Wettable powders (WP) and dry flowable (DF) are formulated in such a manner as to be readily suspendable in water. Dusts (D) should not be mixed in water, but applied directly to the plant. Emulsifiable con- centrate (EC) fungicides contain an emulsifying agent that makes them readily suspendable in
water. Flowable (F) fungicides are finely ground wettable powders that are suspended in a liquid.
Some soil fungicides are available as gran- ules and are applied in the furrow at planting. Dust and spray fungicides may also be used as in-furrow treatments for seedling disease control.
Table II gives trade names and rates of broad spectrum fungicides for controlling foliar dis- eases of vegetables. Applying foliar fungicides to vegetables is best done by spraying, because it provides coverage of all plant surfaces. Foliar fungicides are available in dust formulations, but dusts are usually not as effective as sprays.

Never attempt to use dust formulations of fungi- cides in spray solutions. Dusts will not suspend in the spray solution. Wettable powder formula- tions may appear similar to dusts, but they are formulated to be suspended in spray solutions.
Foliar sprays will aid in controlling leaf spots, rusts, mildews, anthracnose and fruit rots. Foliar sprays are not effective against vascular wilts or root rots. Foliar sprays are protectants, because they form a protective layer of fungicide over the surface of the fruit and foliage. Disease agents (bacteria and fungi) that land on these fungicide-coated surfaces are killed or prevented from infecting the plant.
Most fungicides are not effective in inhibit- ing disease organisms once they have infected a plant. It is imperative that foliar fungicides be applied prior to infection of the plant. A spray schedule should be followed that maintains a protective fungicide layer on the foliage and fruit during favorable infection periods. By carefully monitoring their vegetables, some gardeners can usually delay the first fungicide
application until the first sign of disease. Then a 7-14 day spray schedule should be followed. During rainy or humid weather, spray applica- tion intervals should be shortened.
Proper pesticide mixing and spraying plays a very important part in achieving disease control. Most home gardeners will find a 1-2 gallon compressed-air sprayer adequate for applying foliar sprays. A nozzle with a cone pattern will provide the most effective coverage of plant foliage. Keep the pressure up to insure small spray particle size and good coverage.
Sprayers should be cleaned and rinsed after each use. Hose-end sprayers are not very effec- tive in applying fungicides to vegetables. Never use the same sprayer for fungicides and insecti- cides that has been used for herbicides. Residues of certain types of herbicides are very difficult to remove from sprayers. These residues may cause crop injury if a herbicide-contaminated sprayer is used in applying fungicides or insecticides.
Homeowners should protect themselves when mixing or applying pesticides. Always read the label for use directions and precaution statements.

Disease	Symptoms	Chemical & Formulation1	Approximate Rate/Gallon2	PHI3	Limitations
ASPARAGUS
Root Rot (Fusarium)	Deterioration of root system and poor growth of plants.	Mancozeb 75 DF	1 TBSP		Pre-plant root dip.
Rust	Numerous small, reddish- yellow spots on spears and ferns.	Mancozeb 75 DF	2 TBSP	180	Apply to ferns after harvest of spears. Make applications at 7-10 day intervals, beginning at first appearance of disease.
BEAN (SNAP)
Anthracnose	Brown spots on leaves, sunken with pinkish ooze.	Basic copper sulfate 53WP Chlorothalonil 54 F	mfg directions 3 tsp	0 7	Use western-grown seed. If plants become infected, do not work while plants are wet. Spray at weekly intervals. Do not plant beans in field for at least two years following occurrence of disease. Plow infested bean trash deeply into soil. Do not graze treated areas or feed treated plants to livestock.
Bacterial Blights	Water-soaked spots on leaves and pods. Red margin and sometimes a yellow halo around spot.	Fixed Copper	mfg directions	0	Same applies as for anthracnose.
Gray Mold (Botrytis)	Gray moldy growth on pods and stems.	Chlorothalonil 54 F	3 tsp	7	Begin at 25 to 50% bloom. Repeat at peak bloom. Do not graze treated areas or feed treated plants to livestock.
Mosaic Virus (bean yellow mosaic, bean common mosaic, and peanut stunt viruses)	Yellowed leaves, with or without crinkling or speckling. Leaves cupped, runners killed.				Use resistant varieties. Half runners are most susceptible, particularly “ Pink.’ Make successive plantings, as mosaic is more severe at certain times of the year.
Powdery Mildew	White, powdery mold on surface of leaves.	Sulfur Dust Wettable Sulfur	mfg directions mfg directions	0 0	Use resistant varieties. Spray or dust with sulfur when disease first appears and repeat treatment 10 days later.
Root Rot & Seedling Disease (Rhizoctonia)	Rots of seeds death of seedlings (damping off), and root rots.	Terraclor 75 WP	mfg directions		Apply Terraclor in-furrow at planting. Rotate crops, avoid double cropping beans and turn under plant debris well in advance of planting. (See Extension factsheet SP277-O)
Rust	Reddish brown pustules develop on leaves.	Chlorothalonil 54 F	3 tsp	7	Spray plants when rust appears and repeat at 7-10 day intervals. Do not graze treated areas or feed treated plant parts to livestock.
White Mold (Sclerotinia)	White moldy growth on pods and stems.	Terraclor 75 WP	mfg directions		Spray at first appearance of disease.

Disease	Symptoms	Chemical & Formulation1	Approximate Rate/Gallon2	PHI3	Limitations
BEAN (lima) AND BUTTER PEA
Stem Anthracnose	Reddish brown spots on leaves and pods. Small black specks sometimes can be seen.	Basic copper sulfate 53 W	mfg directions	0	Plant disease-free seed and rotate lima beans with other crops. Start applications of fungicide at first bloom and continue at 7-day intervals.
Root-knot	Swollen, galled root system.				See section above on nematode control.
Root Rot					See Bean, Snap.
BEET
Downy Mildew Leaf Spots	Various leaf spots.	Fixed Copper	mfg directions	0	Spray at first appearance and repeat at 7-10 day intervals.
Rust	Orange to rust colored spots that will rub off on hands.	Sulfur	mfg directions	0
BROCCOLI (SEE CABBAGE)
BRUSSELS SPROUTS (SEE CABBAGE)
CABBAGE
Alternaria Leaf Spot	Target spots on older leaves. Small, black spots may also occur.	Chlorothalonil 54 F Maneb 80 WP	1.5 tsp 3-4 tsp	0 7	Start spraying when this disease first appears. Continue spray at 7- 10 day intervals until disease is under control. Remove excess residues by washing.
Downy Mildew	Yellow areas on upper side of leaves; downy growth on lower surface.	Chlorothalonil 54 F Maneb 80 WP	1.5 tsp 3-4 tsp	0 7
Bacterial Soft Rot	Soft, watery rot occurs, favored by hot, wet conditions. Begin in center of broccoli head.				Control of black rot will also help control bacterial soft rot. Avoid damage to the crop which will provide infection sites for soft rot bacteria.
Black Leg	Lower stem turns brown and rots causing a canker.				Use certified disease-free seeds or transplants.
Black Rot	Yellow V-shaped spots on edge of leaves. Veins near spots turn black.				Use certified disease-free seeds or transplants. Follow good sanitation practices. Don’t grow cabbage in locations where black rot occurred the previous year. See Extension factsheet SP277-P.
Club Root	Galls or clubs on roots. Plants have light green color and are stunted.	Hydrated lime Terraclor 75 WP (transplant solution)	mfg directions 6 TBSP/gal. water		Broadcast and work lime into soil by tilling within 3 days before planting. Apply 3/4 pint of Terraclor solution per plant as a transplant solution.

Disease	Symptoms	Chemical & Formulation1	Approximate Rate/Gallon2	PHI3	Limitations
CABBAGE CONT’D
Damping-Off	Young plants are rotted off at soil line.	Terraclor 75 WP (seedbed drench)	1 TBSP/gal. water/50 sq. ft. seedbed		Sterilize seedbed soil. Apply Terraclor drench after seeding.
Wire Stem	Brown discoloration of stem. Entire stem becomes hard and constricted.	Terraclor 75 WP	10-15 lbs./10,900 ft. of row		Sprayed as 8-inch band centered on row.
Yellows (Fusarium)	Leaves turn yellow. Cross section of stem shows brown discoloration in veins.				Grow resistant varieties in areas where soil is infested. Secure disease-free transplants.
CANTALOUPE
Alternaria Leaf Spot	Tan target spots on leaves, followed by blighting.	Chlorothalonil 54 F Mancozeb 75 DF Maneb 80 WP	1.5-3 tsp 2-3 TBSP 4-6 tsp	0 5 5	Use disease-free seed. Fungicide applications can be delayed until first sign of disease if adequate survey of garden is maintained.
Anthracnose	Sunken spots on fruit and tan leaf spots.
Downy Mildew	Yellow, irregular spots on leaves.
Gummy Stem Blight	Brown, round leaf spots. Cracks on stems with gummy ooze.
Bacterial Wilt	Individual runners suddenly wilt and die.				Apply insecticide to control cucumber beetles, which spread the bacterium. See Extension factsheet SP277-C.
Powdery Mildew	White, powdery mold on surface of leaves.	Sulfur	mfg directions	0	Apply at first sign of disease and repeat at 7-14 day intervals. Do not apply sulfur if temperatures exceed 90 degrees F.
CAULIFLOWER (SEE CABBAGE)
CARROT
Alternaria Blight	Numerous dark brown spots which may coalesce.	Chlorothalonil 54 F	1.5-2 tsp	0	Spray at first appearance and repeat at 7-10 day intervals. Alternaria blight can spread rapidly.
Cercospora Leaf Spot	Small, dark brown to black spots on leaves.	Chlorothalonil 54 F	1.5-2 tsp	0
Southern Blight	White mycelial growth on lower stem; death of plant.				Use crop rotation.

Disease	Symptoms	Chemical & Formulation1	Approximate Rate/Gallon2	PHI3	Limitations
COLLARD, KALE, MUSTARD & TURNIPS
Alternaria Leaf Spot	Brown target spots on leaves.	Fixed Copper Maneb 80 WP	mfg directions 3-4 tsp	0 10	Maintain thin plant stand. Avoid low-lying or poorly-drained soils. Avoid hot part of growing season. Maneb for kale only. Begin sprays when disease is first noticed and repeat at 7-10 day intervals. Use a spreader-sticker for better fungicide coverage.
Anthracnose	Small, tan spots with dark brown margins on leaves.
Cercospora Leaf Spot	Tan leafspots with yellow haloes.
Downy Mildew	Yellow spots on upper surface of leaf with white, downy growth on underside.
CORN (SWEET)
Blights (Helmintho- sporium)	Spots on leaves and drying or blighting of leaves.	Chlorothalonil 54 F Mancozeb 75 DF Maneb 80 WP	0.75-2 tsp 1.5 TBSP 3 tsp	14 7 7	Begin applications when conditions favor disease development and repeat at 4-7 day intervals. Do not apply chlorothalonil to sweet corn to be processed. Do not graze treated areas or feed treated plants to livestock. Use Maneb on crop for seed production only.
Maize Dwarf Mosaic	Alternating light and dark green streaks in leaves. Plants are stunted.				Plant early and preferably in fields not heavily infested with Johnsongrass. Silver Queen, a white variety, has fair tolerance to this disease.
Rust	Bronze, elongate spots.	Chlorothalonil 54 F Mancozeb 75 DF Maneb 80 WP	0.75-2 tsp 1.5 TBSP 3 tsp	14 7 7	See “Blights.”
Stewart’s Wilt	Brown streaks in leaves parallel to veins.				Control corn flea beetle. See insect section of this publication. Also called bacterial blight.
CUCUMBER
Alternaria Leaf Spot	Brown, target spots on leaves.	Chlorothalonil 54 F Mancozeb 75 DF Maneb 80 WP	1.5-3 tsp 2-3 TBSP 2-4 tsp	0 5 5	Use disease-free seed. Fungicide applications can be delayed until first sign of disease if an adequate survey of garden is maintained.
Anthracnose	Brown, irregular spots on leaves, sunken spots on fruit.	Chlorothalonil 54 F Mancozeb 75 DF Maneb 80 WP	1.5-3 tsp 2-3 TBSP 2-4 tsp	0 5 5
Angular Leaf Spot	Brown, angular spots on leaves.	Fixed Copper	mfg directions	0	Spray at first appearance and repeat at 7-14 day intervals. Use disease- free seed. (Copper can injure young plants).

Disease	Symptoms	Chemical & Formulation1	Approximate Rate/Gallon2	PHI3	Limitations
CUCUMBER CONT’D
Downy Mildew	Yellow, irregular spots on leaves.	Chlorothalonil 54 F Mancozeb 75 DF Maneb 80 WP	1.5-3 tsp 2-3 TBSP 2-4 tsp	0 5 5	Use disease-free seed. Fungicide applications can be delayed until first sign of disease if an adequate survey of garden is maintained.
Gummy Stem Blight	Brown, circular leaf spots. Cracks on stems with gummy ooze.	Chlorothalonil 54 F Mancozeb 75 DF Maneb 80 WP	1.5-3 tsp 2-3 TBSP 2-4 tsp	0 5 5
Bacterial Wilt	Starts on individual runners and eventually the entire plant wilts and dies.				Apply insecticide to control cucumber beetles, which spread the disease. See Extension factsheet SP277-C and the insect control section of this publication.
Powdery Mildew	White, powdery mold on surface of leaves.	Sulfur	mfg directions	0	Apply at first sign of disease and repeat at 7-14 day intervals. Do not apply sulfur if temperatures exceed 90 F.
Scab	Sunken spots on fruit.	Chlorothalonil 54 F	2-3 tsp	0	Resistant varieties widely available. Apply at first sign of disease and repeat at 7-10 day intervals.
EGGPLANT
Leaf Blights, Fruit Rots	Spots develop on leaves and fruits.	Fixed copper Maneb 80 WP	mfg directions 3-4 tsp	0 0	Begin spraying before disease appears.
KALE (SEE COLLARD)
MUSTARD (SEE COLLARD)
OKRA
Pod Blight	Young pods fail to develop and deteriorate.				Many times this blight is associated with poor pollination. The fungus Choanephora attacks the flowers and young pods. Providing good air drainage will help prevent infection by Choanephora.
Root-knot Nematode	Swollen, galled root system.				See section above on nematode control.
Verticillium Wilt	Yellowing of leaves. Inside of stem will have brown discoloration.				Rotate okra with crops which are not susceptible to Verticillium wilt.

Disease	Symptoms	Chemical & Formulation1	Approximate Rate/Gallon2	PHI3	Limitations
ONION
Downy Mildew	Pale green, oval, sunken spots on leaves. Purplish mold may be in spots.	Chlorothalonil 54 F Mancozeb 75 DF Maneb 80 WP	1.5-3 tsp 3 TBSP 2-6 tsp	14 7 7	Apply when disease first appears and repeat at 7-10 day intervals. Do not apply Mancozeb or Maneb on exposed bulbs. Do not apply Chlorothalonil within seven days of harvest on dry-bulb onions or within 14 days on green onions, leeks or shallots. Do not apply Chlorothalonil to sweet Spanish onions.
Leaf Blast (Botrytis)	White to tan streaks on leaves. Leaves eventually die.
Purple Blotch (Alternaria)	Purple target spots on leaves.
PEA (SOUTHERN)
Cercospora Leaf Spot	Light to dark brown spots on leaves.	Chlorothalonil 54 F	1.5-2 tsp	42	Spray at early bloom and repeat at 7-10 day intervals. For use on beans harvested dry with pods removed (blackeye pea only). Only Bravo 720 or Bravo DG is labeled. Do not graze treated areas or feed treated plants to livestock.
Rust	Bronze to rust-colored spots that will rub off on hand.	Chlorothalonil 54 F	1.5-2 tsp	42
Mosaic Virus	Mosaic of leaves (alternate light and dark green areas). Distortion of leaves and pods.				Use virus-free seed. Plant resistant varieties.
Powdery Mildew	Dull white, felt-like growth on leaves.	Sulfur	mfg directions	0	Spray at first appearance at 7-10 day intervals.
Root Rot	Brick-red lesions on lower stem and roots. Roots later die.				See Bean, Snap.
PEPPER
Bacterial Spot	Black, angular spots appear on leaves. Dark raised spots also occur on fruits. Plants shed infected leaves.	Fixed Copper Plus Maneb 80 WP	mfg directions mfg directions	0	Use disease-free seed or buy disease-free transplants. Spraying with fixed copper will help prevent spread.
Blossom-end Rot	Tan sunken areas on blossom end and side of fruit.				Lime soil to provide adequate calcium. Avoid planting on droughty soils. Do not use excessive nitrate fertilizer. Irrigate and follow culture practices that tend to provide the most uniform soil moisture.
Cercospora Leaf Spot	Circular spots with gray centers develop on leaves.	Fixed copper Maneb 80 WP	mfg directions 3-6 tsp	0 7	Apply fungicide when disease appears and continue as needed on a 7-10 day schedule.
Anthracnose	Sunken spots on ripening fruit.	Fixed copper Maneb 80 WP	mfg directions 3-6 tsp	0 7

Disease	Symptoms	Chemical & Formulation1	Approximate Rate/Gallon2	PHI3	Limitations
PEPPER CONT’D
Phytophthora Blight	Rapid wilt and death of plants in wet areas of field.				Plant on raised bed.
Root-knot	Swollen, galled root system.				See previous section on nematode control.
Southern Blight	Plants wilt and die. White mold can often be seen on base of stem.	Terraclor 75 WP (soil treatment)	mfg directions		Turn soil deep to bury plant debris that might harbor disease organism. Use Terraclor in setting water at planting. Rotate with sod crops.
Sun Scald	Dry, white bleached spot on side of pod exposed to sun.				Fruits on plants kept in a healthy, vigorous condition are not likely to be injured by sun scald. Control of bacterial spot will prevent loss of leaves and keep the fruit protected from the sun.
POTATO, IRISH
Early Blight	Small brown, target spots appear on leaves in hot, wet weather.	Chlorothalonil 54 F Mancozeb 75 DF Maneb 80 WP	1-1.5 tsp 1-2 TBSP 3-4 tsp	0 14 14	Start applications when plants are 4-6 inches high and continue at 7- 10 day intervals.
Late Blight	Water-soaked irregular spots on leaves in cool, wet weather. Plants appear scalded.	Chlorothalonil 54 F Mancozeb 75 DF Maneb 80 WP	1-1.5 tsp 1-2 TBSP 3-4 tsp	0 14 14
Black Leg	Stem turns black. Plant wilts and dies.				Plant certified seed.
Rhizoctonia Canker (Black Scurf)	Black cankers girdle stem, causing poor growth.	Terraclor 75 WP	mfg directions
Scab	Rough, scabby spots on tubers.				Use disease-free seed. Where soil is infested with scab organism, use resistant varieties and rotate crops. See SP277-G.
Seed Piece Decay	Rotting of seed piece.	Mancozeb Maneb	Use dust formulations according to mfg directions		Treat seed pieces with fungicide dust before planting. Plant seed pieces immediately after treating. Do not use treated seed pieces for food, feed or oil purposes.
Ring Rot	Brown discoloration of vascular tissue in tuber.				Plant certified disease-free seed and practice crop rotation.
Virus Diseases	Curling, streaking, or mosaic in leaves. Plants may be stunted.				Plant certified disease-free seed and practice crop rotation.

Disease	Symptoms	Chemical & Formulation1	Approximate Rate/Gallon2	PHI3	Limitations
PUMPKIN
Downy Mildew	Yellow, irregular spots on leaves.	Chlorothalonil 54 F Maneb 80 WP	1.5-3 tsp 3-4 tsp	0 5	Begin spraying at first sign of disease. See label for spray intervals. Use higher rates for scab control.
Gummy Stem Blight	Black, circular spots on fruit.
Microdochium Blight	White dashes on stem surface.
Scab	Sunken or raised spots on fruit.
Mosaic Virus	Green patterns on fruit.				Reflective mulches, aphid control, and weed control may be helpful. Control is difficult.
Powdery Mildew	White, powdery mold on leaf surface.	Sulfur	mfg directions	0	Begin spraying at first sign of disease.
SPINACH
Downy Mildew (Blue Mold)	Yellow spots on upper leaf surface. Gray downy fungus on underside of leaf.	Basic copper sulfate 53 WP	mfg directions	0	Start fungicide applications at first sign of disease and continue at 7-10 day intervals as necessary. Where white rust has been a problem in the past, spraying should start when the first true leaves develop. “Fall Green,” a fall variety, is moderately resistant to white rust and several races of blue mold.
White Rust	Yellow spots on upper leaf surface. White powdery mass on underside of leaf.	Basic copper sulfate 53 WP	mfg directions	0
SQUASH
Downy Mildew	Yellow, irregular spots on leaves.	Chlorothalonil 54 F Mancozeb 75 DF Maneb 80 WP	1.5-3 tsp 2-3 TBSP 3-4 tsp	0 5 5	Begin spraying at first sign of disease. See label for spray intervals.
Powdery Mildew	White, powdery mold on leaf surfaces.	sulfur	mfg directions	0	Apply at first sign of disease and repeat at 7-14 day intervals. Do not apply sulfur if temperatures exceed 90 F.
Scab	Sunken or raised spots on fruit.	Chlorothalonil 54 F	2-3 tsp	0	Begin spraying at first sign of disease. See label for spray intervals.
Blossom Blight	Blossoms rot and stick to young fruit. The end of the fruit turns black.				Provide good air circulation for rapid drying.
Mosaic Virus	Greening of fruit. Leaves mottled, veins stunted.				Reflective mulches may be of some value. The yellow-stemmed varieties Multipik, Superpik and Supersett are tolerant of watermelon mosaic virus.

Disease	Symptoms	Chemical & Formulation1	Approximate Rate/Gallon2	PHI3	Limitations
SWEET POTATO
Black Rot	Black spot on roots. Dry, black decay extends in flesh of root.				Use certified seed. Do not replant for 3 years in locations where this disease has been present.
Scurf	Brownish black discoloration on surface of potato.
Cork	Small, black, corky spots in potatoes. Spots do not extend to surface.				Use certified, disease-free seed.
Root-knot Nematodes	Longitudinal cracking of potato.				See previous section on nematode control.
Soil Rot (Pox)	Circular sunken areas on fleshy roots. Feeder roots are blackened.				Rotate sweet potatoes with other crops. Maintain pH below 5.2 in infested fields. Grow a resistant variety.
Stem Rot (Fusarium Wilt)	Plants are yellow and stunted. The interior of the vine shows a brown discoloration.				Select disease-free seed stock by examining vines of each hill. If cross section of vine shows a brown discoloration, do not use roots for seed stock.
Southern Blight (Plant Bed)	Plants die in spots in bed. White growth on lower stem.				Use new soil in beds each year.
TOMATO
Bacterial Spot	Small, raised spots on fruits. Water-soaked spots on foliage.	Fixed Copper plus Mancozeb 75 DF OR plus Maneb 80 WP	mfg directions 1.5-2 TBSP 3-4 tsp	0 5 5	Use hot water seed treatment or use disease-free seed.
Blossom-End Rot	Black spot on blossom end of small green fruit.				Maintain adequate calcium level in soil and uniform soil moisture. Plant least susceptible varieties. Avoid droughty soils.
Early Blight	Brown target spots followed by blighting of foliage.	Chlorothalonil 54 F Mancozeb 75 DF Maneb 80 WP	1.5-2 tsp 1.5-3 TBSP 3-6 tsp	0 5 5	Start preventative spraying as soon as plants are established in the garden. Spray at 7-10 day intervals. During periods favorable for disease development, shorten the spray interval. Maneb 80 WP can be used in the greenhouse and in the garden.
Anthracnose	Circular, sunken spots on ripe fruit.
Septoria Leaf Spot	Small, gay circular leaf spots with dark borders.
Buckeye Fruit Rot	Circular, zonate bands within large spot on fruit, worse on lower clusters.				Mulch and stake plants to keep soil off fruit clusters.

Disease	Symptoms	Chemical & Formulation1	Approximate Rate/Gallon2	PHI3	Limitations
TOMATO CONT’D
Fusarium Wilt	Yellowing and wilting of foliage. Inside of stem has brown discoloration.				Use a resistant variety and rotate tomato fields. Obtain disease-free plants and plant on disease-free soil.
Gray Mold (Botrytis)	Leaves turn brown from tip back; gray mold can be seen on foliage during humid weather.	Chlorothalonil 54 F	3 tsp	0	Begin fungicide spray applications at first sign of disease.
Late Blight	Irregular, watersoaked spots on leaves. Occurs in mold, wet weather.	Chlorothalonil 54 F Mancozeb 75 DF Maneb 80 WP	1.5-3 tsp 1.5-3 TBSP 2-6 tsp	0 5 5	Follow spray schedule for early blight. If weather conditions are favorable for late blight, shorten spray interval. Obtain disease-free plants and plant in non-infested soil.
Leaf Mold	Yellow spots on upper surface of leaves. Olive to gray mold on underside of leaves. Primarily in greenhouses.	Chlorothalonil 54 F	1.5-2 tsp	0	Fungicides will control leaf mold in the garden, but are not adequate in greenhouse production. The best control in greenhouse tomatoes is the use of resistant varieties and regulation of humidity.
Pythium Stem Rot	Dark, water rot of lower stem of young plants.
Southern Blight	Plants wilt and die. White mold can often be seen on base of stem.	Terraclor 75 WP (soil treatment)	mfg directions		Turn soil deep to bury plant debris which might harbor disease organisms. Use Terraclor in setting water. Rotate with turf.
Verticillium Wilt	Yellowing of leaves; inside of stems will have brown discoloration.				Use resistant varieties. Practice long rotations of tomatoes with other crops.
TURNIP (SEE COLLARDS)
WATERMELON
Alternaria Leaf Spot	Brown, target spots on leaves.	Chlorothalonil 54 F Mancozeb 75 DF Maneb 80 WP	1.5-3 tsp 2-3 TBSP 2-4 tsp	0 5 5	Begin at first sign of disease. See label for spray intervals. Plant anthracnose- resistant varieties. Mancozeb and Maneb are not labeled for scab control.
Anthracnose	Brown irregular spots on leaves and sunken spots on fruit.
Cercospora Leaf Spot	Tiny, dark brown spots.
Downy Mildew	Yellow, irregular spots on leaves.
Gummy Stem Blight	Irregularly circular leaf spots. Cracks on stems with gummy ooze.
Scab	Small, raised warts on fruit.
Fusarium Wilt	Yellow and wilting of leaves. Brown discoloration in interior of vine.				Grow resistant varieties. Long rotations should be practiced even where resistant varieties are used.

Table II. Common Names and Trade Names of Chemicals for Controlling Diseases of Vegetables

Common Names	Trade Names1
benomyl	Note: Home garden benomyl products are no longer available.
chlorothalonil	Bravo 720 (54%) Bravo 75 WP Bravo 90 WDG Bravo Flowable Fungicide Broad Spectrum Liquid Fungicide Fungi-Gard Lawn, Ornamental and Vegetable Fungicide Vegetable Disease Control
fixed coppers	Basicop Blue Shield Kocide Tri-Basic Copper Sulfate
mancozeb2	Dithane DF Manzate 200 DF Penncozeb
maneb2	Maneb 80 WP Maneb Spray Maneb Liquid Fungicide
PCNB	Terraclor 10 G Terraclor 75 WP

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