Vegetable Diseases

Specific virus diseases are difficult to distinguish and produce a wide range of symptoms including stunted, slow-growing plants, twisted, crinkled, cupped, or deformed leaves, and leaf discoloration (yellow mottling and mosaic patterns, ringspots, and dark-green banding).

Many bacteria, fungi, and viruses can cause blights. Southern blight is caused by the fungus Sclerotium rolfsii. Most blights are favored by certain weather conditions, such as hot and humid or cool and moist.

Symptoms of verticillium include older leaves turning yellow, dying, and dropping off infected plants.

Powdery mildew is a common fungal disease that grows as a white powdery coating over the surfaces of leaves. It has a wide host range.

Sweet potatoes that develop dark spots on their skin surface may be infected with a fungal disease called scurf.

Phytophthora is a soil-borne fungal disease that may infect pepper, tomatoes, squash, cucumbers, and eggplant.

Late blight is the plant disease that caused the Irish Potato Famine in the 1840s. This water mold disease is potentially destructive to tomatoes and potatoes that are grown in Maryland, but it rarely occurs here.

Tomato blossoms can drop off plants for a few reasons. Gray mold or botrytis is one of them.

There can be numerous causes of tomato plant wilting and they should be ruled out before suspecting fusarium wilt.

Early blight is a very common foliar disease of tomato plants that can result in defoliation and reduced yields.