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Plant Disease

Growing isn't always easy. When plant problems present themselves, you can count on WVU Extension specialists and agents for trusted, research-based advice. Learn about common plant diseases.

Browse the Plant Disease Identification Guide

Extension experts help identify, prevent and find solutions to recover from stress, injury and disease in all types of plants. Contact the WVU Extension Service when your plants get sick.

Plant Disease Identification Guide

Plant Diagnostic Clinic

Contact the Clinic

WVU Plant Diagnostic Clinic

G102 South Agricultural Sciences
Morgantown, WV 26506-6108
email Email Mahfuz Rahman
phone 304-293-8838 phone 304-288-9541

Monday - Friday | 8:15 a.m. - 4:45 p.m.
Closed on WVU Holidays

Collect & Submit Plant Samples

Take & Submit a Plant Sample


Active Plant Disease Alerts

AgAlert! Threat of Corn Ear Mold in West Virginia

Above average rainfall and continued wet weather has slowed field corn dry-down and delayed harvest across the state this fall.

This situation has created several problems, including encouraging the growth of corn ear mold and reducing grain quality. In some cases, these types of mold may also pose a risk of mycotoxin contamination of the kernels, depending on what type of fungal growth dominates, and thereby, affecting the overall grade of the corn.

Photo of moldy ear of corn on stalk

Read AgAlert! Threat of Corn Ear Mold in West Virginia

AgAlert! Cucurbit Downy Mildew

Cucurbit downy mildew (CDM) is a destructive disease on most of the members of the gourd family or Cucurbitaceae such as cucumber, cantaloupe, pumpkin, squash, watermelon and zucchini. Cucumbers are the worst affected cucurbit that can be completely killed in two weeks from the onset of the disease.

The disease-causing organism is spread by air current from south to north during the growing season in most years. Optimum conditions for sporulation of the causal agent (Pseudoperonospora cubensis), which is an obligate parasite (an organism that can grow only as a parasite in association with its host plant and cannot be grown in artificial culture media) are 59°F with 6-12 hours of moisture present (usually in the form of morning dew or rain droplets on foliage).

CDM regional map is showing outbreak of the disease all around West Virginia, including some of the West Virginia counties, and this is the most critical time to take preventative measures against the disease.

Read AgAlert! Cucurbit Downy Mildew

AgAlert! Late Blight of Tomato & Potato

Late blight of tomatoes

Late blight has been detected in Jefferson County, West Virginia. This is still early in the season, and many growers may have not even harvested yet.

Considering the rainy and humid weather forecast, both organic and conventional growers should take some preventative measures.

Read AgAlert! Late Blight of Tomato & Potato

Ag Alert! Fire Blight on Apple & Pear Trees

A close up view of fire blight on an apple tree.

2018 is a bad year for fire blight on pome fruit (apple and pear) partly due to the odd combination of bloom time, temperature and rainfall. In a regular year, most bloom occurs while temperature still below 60° F (minimum temperature required for bacterial infection through flowers).

This year it was delayed but as soon as bloom occurred temperature crossed 60° F mark and rain followed. However, WVU Extension's disease forecast-based spray schedule helped commercial growers keeping disease pressure low. The disease is more widespread at home sites.

Read Ag Alert! Fire Blight on Apple & Pear Trees

If you see or suspect a new plant disease outbreak that's not currently reported here, please contact Mahfuz Rahman with the WVU Plant Diagnostic Clinic or your local county Extension agent, immediately.

Expert Plant Disease Help