Peanut Mottle
Causal Agent
Peanut mottle virus
Hosts
Peanuts
Symptoms
The symptoms of PMV infection can vary with cultivar, time of infection, and environment. The most common symptom, although it may not be readily noticed, is a mild mottle or mosaic on the youngest leaves of infected plants. The light and dark green areas of affected leaves can best be seen if leaves are held up to light. Margins of leaflets may curl up and depressions in the leaf tissue between the veins may become prominent. Plants are generally only mildly stunted, if at all. As plants mature, the symptom expression generally declines, particularly during hot and dry weather. Pods from infected plants may be reduced in size and have irregular gray to brown patches. The seed coat of affected seed may also be discolored.
Control
Because the virus generally has a minor effect on commercial peanut yields, no specific management practices are recommended for control of PMV. Several breeding lines with resistance have been identified, but this resistance has not been incorporated into any commercial varieties. The use of PMV-free seed is the most feasible approach for control, as this prevents the disease from becoming initially established in the field. If PMV-free seed is used, volunteer plants must be completely removed and the field situated so that PMV hosts, such as clovers, southern pea, and navy bean are at least 100 yards away. Please contact your local county extension office for current information.