Stem End | Cornell Vegetables

Note: Lesions near the stem end are often large and some are associated at or near the calyx.

Early blight | See factsheet for more information (LIHREC)

lesions on the tomato stem end of fruit — Photo courtesy of Meg McGrath, Cornell University, NY.

Symptoms: dark brown to black, leathery, sunken spots. Concentric rings form at the stem end.

Gray mold | See factsheet for more information (LIHREC)

diseased tomato stem and fruit — Photo courtesy of Meg McGrath, Cornell University, NY.

Symptoms: soft rot with skin breaks. Gray, fuzzy fungal growth develops and white rings will be present.

Powdery mildew (Oidium) | See factsheet for more information (LIHREC)

diseased tomato leaves — Photo courtesy of Meg McGrath, Cornell University, NY.

Symptoms: Powdery growth on individual sepals of the calyx, but does not directly infect the fruit.

Pythium rot

three diseased tomato fruit — Photo courtesy of T.A. Zitter, Cornell University, NY.

Symptoms: starts as small water-soaked lesions from contact or in proximity with soil. White, cottony, aseptate mycelia soon develop and fruit becomes watery.

Septoria leaf spot | See factsheet for more information (LIHREC)

diseased tomato plant — Photo courtesy of Chris Smart, Cornell University, NY.

Symptoms: dark brown lesions on sepals of the calyx, but does not directly infect the fruit. Leaves, stems, and petioles can also be infected.

Sour rot (Geotrichum)

four diseased tomato fruit — Photo courtesy of T.A. Zitter, Cornell University, NY.

Symptoms: rot begins at stem scar followed by whitish fungal growth. This can occur on mature green and ripe tomatoes. A sour odor is evident.

Trichothecium

diseased tomato fruit and leaves — Photo courtesy of A.F. Sherf, Cornell University, NY.

Symptoms: white fungal growth occurring near the calyx.

White mold (timber rot) | See factsheet for more information (LIHREC)

one collapsed tomato fruit — Photo courtesy of T.A. Zitter, Cornell University, NY.

Symptoms: gray watery rot with rapid fruit collapse. White mold may contain black, pea-like objects where the fungus overwinters (sclerotia).

Tobacco hornworm | See factsheet for more information (LIHREC)

damaged tomato fruit — Photo courtesy of Meg McGrath, Cornell University, NY.

Symptoms: feeding damage on shoulder or near calyx.

Thrips | See factsheet for more information (LIHREC)

seven damaged tomato fruits — Photo courtesy of Meg McGrath, Cornell University, NY.

Symptoms: mouthparts pierce the cuticle causing damage while removing plant sap.

Concentric rings

several damaged tomato fruit — Photo courtesy of T.A. Zitter, Cornell University, NY.

Symptoms: splitting of the epidermis in circular rings, resulting from changing environmental conditions involving moisture.

Radial rings

one damaged tomato fruit — Photo courtesy of T.A. Zitter, Cornell University, NY.

Symptoms: splitting of the epidermis radiating from the calyx to blossom end, resulting from fluctuating environmental conditions involving moisture.

Weather checking

many damaged tomato fruit — Photo courtesy of T.A. Zitter, Cornell University, NY.

Symptoms: small cracks in the cuticle may enlarge considerably if presence of moisture (mist, fog, dew) exists for extended periods of time. Secondary pathogens may invade.

More information/prepared by:

For more information, please contact:
Meg McGrath – mtm3@cornell.edu & Chris Smart – cds14@cornell.edu
Originally prepared for Vegetable MD Online by Thomas A. Zitter.