Photo Gallery

Vegetable Guidelines

Cornell Plant Disease Clinic

Bacterial

• Canker
• Speck
• Spot

Fungal

• Alternaria stem canker (Black Mold)
• Anthracnose
• Early blight
• Gray mold
• Powdery mildew (Leveillula)-does not directly infect fruit
• Powdery mildew (Oidium)-does not directly infect fruit
• Septoria
• Target spot
• White mold

Oomycetes

• Buckeye rot
• Late blight
• Pythium fruit rot

Virus

• Alfalfa mosaic
• Cucumber mosaic
• Potato leafroll
• Tobacco etch
• Tobacco (Tomato) mosaic
• Tobacco mosaic single streak
• Tobacco mosaic & potato virus X-double streak
• Tomato spotted wilt

Viroids

• Tomato planta macho

Phytoplasma

• Tomato big bud

Pre-Post Harvest Rots

• Rhizoctonia soil rot
• Sour rot
• Trichothecium rot

Physiological/Weather

• Blossom end rot
• Catface
• Concentric rings-growth cracks
• Radial rings-growth cracks
• Hail
• Puffiness
• Sunscald
• Weather checking
• Yellow shoulder
• Zippering

• Glyphosate injury

• Spray Mixture Damage
  (Difolatan & sevin & parathion)
• Stinkbug-cloudy spot
• Lygus plant bug
• Thrips
• Hornworm
• Broad mite
• Whitefly

• Undetermined etiology-Graywall
• Unknowns

Bacterial speck

tiny black spots; sometimes raised or imbedded  

Bacterial spot

small, brown, scabby, sunken or slightly raised spots

Bacterial canker

white, raised, corky spots; the brown center “birdseye” fruit symptoms do not always occur, like in greenhouses

Target spot

dark brown sunken spots enlarge with cracked centers

Black mold (Alternaria alternata)

infection commonly follows damage, as seen with plant bug feeding

Alfalfa mosaic virus

sunken irregular shaped spots following systemic infection

Cloudy spot (caused by Stinkbugs feeding injury)

yellow to whitish spots of irregular size; white spongy tissue extends into flesh

Lygus plant bug feeding injury

windowpane-like feeding damage; can allow establishment of secondary pathogens

Anthracnose

circular sunken spots; dark center; mature fruit; common 

Late blight

large, firm, greasy, rough, brown spots; distinct edge; sporulation may occur 

Hail injury

irregularly shaped sunken lesions

Buckeye rot 

large, firm, smooth, brown spots; concentric zones 

Yellow/green shoulder

area affected is exposed to sun, and chlorophyll fails to change as fruit matures

Gray mold 

soft rot; skin breaks; gray fuzzy fungal growth; white rings

White mold (timber rot) 

gray watery rot; rapid collapse; white mold may contain black, pea-like objects (sclerotia)

Early blight

dark brown to black, leathery, sunken spots; concentric rings; at stem end

Concentric rings

splitting of epidermis in circular rings, resulting from changing environmental conditions involving moisture

Radial rings

splitting of epidermis radiating from the calyx to blossom end; fluctuating environmental conditions involving moisture.

Weather checking

small cracks in the cuticle may enlarge considerably if presence of water (mist, fog, dew) exists for extended periods of time; fungi may invade

Thrips

mouthparts pierce the cuticle causing the damage while removing plant sap

Pythium rot

starts as small water-soaked lesion from contact or in proximity with soil; white, cottony, aseptate mycelium soon develops and fruit becomes watery

Sour rot (Geotrichum)

rot begins at stem scar followed by whitish fungal growth; can occur on mature green and ripe tomatoes; a sour odor is evident

Trichothecium

white fungal growth occurring near calyx

Hornworm

feeding damage on shoulder or near calyx

Buckeye rot 

large, firm, smooth, brown spots; concentric zones

Blossom-end rot

dark brown to black, leathery spot at blossom end

Catfacing 

dark brown firm streaks (scars) at blossom end

Rhizoctonia soil rot

usually occurs on ripening fruit on or in close proximity to soil; initially firm, but becomes a watery rot

Glyphosate injury

symptoms mimicking catface-like symptoms

Powdery mildew (Oidium)-does not directly infect fruit(shown here on calyx)

Septoria leaf spot

dark brown lesions on sepals of calyx; not directly infecting fruit

Tobacco (Tomato) mosaic virus

fruit symptoms will vary depending on virus strain, and how long the plant has been infected

Potato leafroll virus

puffiness associated with systemic infection with PLRV; other puffiness caused by environmental conditions

Cucumber mosaic virus

CMV infections do not normally cause fruit infection; illustrations from Mediterranean region (Italy)

Tomato spotted wilt virus  

initially small irregular brown spots; brown ring spots; mottling; blotches

Tobacco etch virus

dark green blotches following infection at an early age

Tobacco mosaic virus single streak

TMV symptoms associated with a specific strain

Tobacco mosaic & potato virus X-double streak

firm dark blotches appearing on most of fruit surface

Tomato planta macho

reduced size and irregular ripening associated with viroid infection

Big bud

fruit distortion and irregular ripening

Sunscald

usually seen as whitish area developing on shoulder exposed to direct sunlight

Puffiness

irregular fruit shape and empty locules; associated with environmental conditions

Weather checking

small cracks in the cuticle may enlarge considerably if presence of water (mist, fog, dew) exists for extended periods of time; fungi may invade

Zippering

a thin longitudinal scar extends from the stem scar to the blossom end; occasionally an open hole to the locule forms; defect happens when the flower anthers fuse to the ovary wall of developing fruit and occurs most commonly when fruit set takes place in cool weather

Irregular ripening (whitefly)

irregular ripening of fruit resulting from heavy whitefly occurrence on plant

Gray wall (GW)

typically develops on green fruit prior to harvest; appears as black to dark brown necrotic tissue in the walls of the fruit; TobMV, TomMV have been implicated in some cases of GW, but plants free of virus and those resistant to virus also develop GW

Spray Mixture Damage
(Difolatan & sevin & parathion)

irregularly shaped sunken spots with defined black border and beige centers follow pesticides applied as a mixture