Tomato
Symptom Cause  
Fruits develop small, round, water-soaked spots; later, fruits darken and rot
Anthracnose (on plants)
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Leaves wrinkled or curled; discolored, stunted, tend to fall off
Aphids
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Leaves, stems and buds eaten
Armyworms
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Plants wilt quickly; white, sticky material might be seen when a stem is cut
Bacterial Wilt
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Often cardinals take bites out of fruit
Birds
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Irregular, water-soaked spots may develop on leaves; plant becomes partly defoliated; stem end of fruit becomes grayish-green; blossoms or young fruits may drop
Blight, Early
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Irregular, water-soaked spots may develop on leaves; plant becomes partly defoliated; stem end of fruit becomes grayish-green; blossoms or young fruits may drop
Blight, Late
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Flowers, leaves, roots chewed
Blister Beetles
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Holes in leaves
Cabbage Loopers
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Holes chewed in leaves
Colorado Potato Beetle
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Holes in leaves
Corn Earworms
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Holes chewed in leaves, leaf stalk, stems; plant wilts, dies.
Cucumber Beetles
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Seedling cut off at soil
Cutworms
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Plant gradually wilts, sawdust trail around stem
European Corn Borers
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Leaves riddled with shot holes; plant weakens
Flea Beetles
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Leaves yellow and droop; cross-section of stem shows brownish liquid within; fruit usually decays and drops
Fusarium Wilt
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Soft, watery spots on stems, leaves or fruit; enlarge, mold forms
Gray Mold (Botrytis Blight)
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Leaves skeletonized
Hornworms
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Holes in leaves and flowers
Japanese Beetles
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Foliage yellowed or white mottling, glaze of honeydew; plant weakens
Leafhoppers
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Cottony white masses on roots, stems, branches leaves; reduced plant vigor
Mealybugs
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Mottled leaves; young leaves are bunched or puckered; plants are stunted; yield is decreased; fruit is also mottled
Mosaic Viruses
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Plant stunted, leaves yellowed, root lesions
Nematodes
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White spots on leaves; eventually entire leaf is covered with powder
Powdery Mildew
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Leaves yellowed and may drop
Psyllids
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Ragged holes in middle of leaves
Slugs and Snails
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Leaves stippled, yellowing or bronze; dry out and drop may be webbing visible; sometimes galls form on leaves
Spider Mites
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Bites taken out of tomato
Squirrels
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Leaves discolored; black fecal spots on underside of leaf.
Thrips
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Leaves skeletonized
Tomato Hornworm
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Yellowing of foliage and gradual defoliation; plants may become stunted
Verticillium Wilt
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Weakened plant, leaves yellowed, appears like flying dandruff when foliage disturbed
Whiteflies
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