Bean Pod Mottle Virus is caused and spread by the bean leaf beetle. Infection occurs early in the growing season, leaving the leaves distorted, blistered, wrinkled and mottled color pattern, typically on younger leaves. Infection later in the season can result in mottling on the soybean pod, and mottling on the soybean seed. BPMV can be confused with herbicide injury, to be sure tests can be sent into university labs for testing. BPMV can be spread by bean leaf beetles overwintering and from perennial weeds in the Desmodium species. During cool weather is the best time to see symptoms, during hot weather the symptoms seem to disappear. Symptoms can appear throughout the growing season. Seed can also be infected from the previous growing season.
When scouting take into consideration bean leaf beetle populations and look for them when scouting. Late vegetative, early reproductive and R3-R6 stages are when beetle populations are at their highest. The youngest leaves are the most susceptible and should be looked at first for symptoms. These include the leaves being distorted, blistered, wrinkled and mottled color pattern on the leaf.
- Delaying planting, early planted fields are more at risk for infection
- Insecticide seed treatment
- Foliar-applied insecticides used to control bean leaf beetle populations.