By Emmanuel Byamukama, Alison Robertson and Forrest W. Nutter Jr.
Iowa State University Department of Plant Pathology

In a recent 3-year survey study conducted during the 2005 through 2007 soybean growing seasons, BPMV was found to be one of the most prevalent soybean diseases in Iowa, with BPMV being detected in 10 percent (2005) to 40 percent (2006) of the approximately 1,200 soybean fields sampled and tested each growing season. By mapping BPMV incidence at the county scale, BPMV incidence (risk) was found to occur at varying intensities within and among Iowa counties. Generally, risk of BPMV tended to decrease in a gradient from south to north within county tiers.

Three potential sources of BPMV inoculum in Iowa are:

  • overwintering infested bean leaf beetles
  • BPMV-infected seed
  • alternative weed hosts infected with the virus (primarily legume weeds such as Desmodium spp)

High levels of BPMV can develop if large populations of bean leaf beetles can successfully survive the previous Iowa winter.

Read the rest of the article with more on the virus and risk predictions for 2010.

SOURCE: Iowa State University.