Incidence of Alfalfa mosaic virus, Bean pod mottle virus, and Soybean mosaic virus in Nebraska Soybean Fields

Abstract

The incidence of soybean viruses is increasing across the North Central Region of the United States as indicated by survey efforts and grower reports from several states. To determine the level of virus infection in Nebraska, we surveyed soybean fields for two consecutive years. Alfalfa mosaic virus (AMV) was detected in 52% of the fields in 2001 and in 56% of fields in 2002. The incidence of Bean pod mottle virus (BPMV) varied more, with 54% of fields testing positive in 2001 and 91% testing positive in 2002. Soybean mosaic virus (SMV) was not detected in 2001, but it was detected in 31% of fields in 2002. The widespread distribution of detected SMV in 2002 is suggestive of introduction with seed. The incidence of BPMV was significantly higher in fields planted earlier than the recommended optimum planting date in one of the two years studied. The widespread incidence of AMV and BPMV and the irregular occurrence of SMV indicate that further studies of soybean viral diseases in Nebraska are warranted. Accepted for publication 13 March 2006. Published 24 April 2006.