Effects of Delayed Harvest on Soybean Seed Quality following Bean Leaf Beetle (Coleoptera: Chrysomelidae) Pod Injury

A 2 yr study was done to determine if delaying harvest of soybeans having bean leaf beetle-injured pods would result in further reductions of seed quality. Beginning at harvest maturity, collection of soybean pods was done every 2 wk, after which seeds from bulk harvest, from injured and uninjured pods, and from underneath feeding lesions or locations without lesions, were tested for seed germination and disease presence. Seed from uninjured pods showed no significant loss in germination percentage nor increase in disease incidence, even when seeds were harvested 6 wk following harvest maturity. When pod injury is low, a delay in harvest would not be of great concern. However, germination decreased and the percentage of infection by seed pathogens increased on seeds from injured pods and from underneath feeding lesions when harvest was delayed. When bean leaf beetle pod injury is high, immediate harvest at maturity is necessary to prevent further germination loss and incidence of fungal pathogens.