Fact Sheets - Vegetable Diseases
For more vegetable disease information reference the Vegetable Pests of Utah Guide and Utah Vegetable Production and Pest Management Guide
Botrytis Neck Rot of Onion
Botrytis neck rot is a post-harvest storage disease. It is caused by the fungi Botrytis aclada and B. allii. Infections occur in the field mainly through uncured necks but pathogen remains inactive until weeks later.
Candidatus Liberbacter of Pepper
The non-culturable bacterium Candidatus Liberibacter solanacearum infects peppers. Bacteria are transmitted by potato psyllids. Bacteria are transmitted throughout the lifetime of the insect and can also infect tomatoes and potatoes.
Curly Top of Tomato
Beet Curly Top Virus (BCTV) is taxonomically a Curtovirus in the Geminiviridae family of plant pathogenic viruses. It is vectored, or carried, by the beet leafhopper (BLH) insect. BCTV causes curly top of tomato, a comon disease in Utah and the western U.S.
Damping-Off
Damping-off is caused by several soilborne fungi. The fungi thrive in wet conditions. Some have motile spores that can swim in water from root to root. It can easily be prevented by good sanitation and good cultural practices.
Iris Yellow Spot Virus in Onions
Iris Yellow Spot Virus (IYSV) is a damaging viral pathogen of onions. The disease can devestate an onion field by destroying the photosynthetic area of the leaves of infected plants, thus reducing the ability of the plant to develop bulb size and directly affecting yield and grade of onions at harvest
Powdery Mildew on Vegetable Crops

COMING SOON
Pink Root Disease of Onions
The disease is caused by the fungus Phoma terrestris. Fungus is commonly found in soil. Infects roots but not basal plate or fleshy scales. Disease can get worse when onions are planted after cereals or in very short rotation with onion.
The Backyard Garden: Leafy Green Pests
COMING SOON
The Backyard Garden: Tomato Pests

COMING SOON
Tomato Spotted Wilt Virus of Tomato & Pepper
Tomato spotted wilt virus (TSWV) most commonly affects tomatoes, peppers and tomatillos. It has also been found in ornamental plants such as blanket flower, and zinnia and weeds. TSWV has become more prevalent in Utah in recent years.
Zebra Chip Disease of Potato
The non-culturable bacterium Candidatus Liberibacter solanacearum causes zebra chip disease of potatoes. Bacteria are transmitted by potato psyllids. Bacteria are transmitted throughout the lifetime of the insect and can also infect tomatoes and peppers.