Monitoring Bean pod mottle virus and Soybean mosaic virus Incidence at Different Soybean Growth Stages in Alabama

Abstract

This study focuses on Bean pod mottle virus (BPMV) and Soybean mosaic virus (SMV) incidence over time relative to stages of plant growth in selected fields in Alabama. Five commercial soybean fields in west-central Alabama were surveyed for BPMV and SMV in 2010-2012 and 2014. Incidence of BPMV was typically highest at crop maturity. Incidence of 10% or higher was recorded at full bloom in at least one field in each year of the study, but incidence did not exceed 23% at bloom in any field with one exception. SMV was not detected at high levels during this study and incidence above 10% at full bloom was recorded for only one field. Results from this study, combined with observations from a previous statewide survey, indicate that BPMV is the most common virus disease of soybeans in Alabama. BPMV has the potential to cause yield loss in years when bean leaf beetles, its most important vector, are present at high levels early in the season when infection of soybean prior to flowering is possible. Results also suggest that SMV incidence in soybean in Alabama is low in most years and the disease might not pose a significant threat to soybean production at this time, especially in the absence of high populations of soybean aphids in the state.