Bean Pod Mottle (BPM)
Symptoms:
- Green to yellow mottling of young leaves, and leaves may become distorted in severe cases.
- Symptoms may not be at high temperatures or after pod set.
- Pod formation may be reduced when plants are under moisture stress.
- BPM may be one cause of green stem syndrome where plants retain green stems and leaves after pods and most nearby plants have matured.
- This virus has been associated with green stem syndrome, and can interact with soybean mosaic virus (SMV) to create very severe symptoms.
Pathogen Involved:
- Bean pod mottle virus (BPMV).
- Transmitted by leaf-feeding beetles such as the bean leaf beetle. Seed transmission rates are very low.
- Host range includes common bean and some clovers.
Time of Occurrence:
- All season.
Conditions Favoring Disease:
- Cool temperatures.
- Infection that occurs early in season.
- Presence of bean leaf beetles that transmit the virus when feeding. Reduced following severe winters that result in poor survival of beetles.
Disease Management:
- At this point effective management tactics are not available.
- Resistant varieties have not been developed
- The value of insecticides for controlling bean leaf beetle transmission is uncertain.