Source: CropBiotech Update

Cowpea is widely used as food and animal feed, but it is also beset by viruses and pests. Important viruses include the cucumber mosaic virus (CMV) and the blackeye cowpea mosaic virus (BlCMV). Together, these two viruses cause cowpea stunt disease, which results in significant losses in the crop. There are available sources of resistance to BlCMV, but these need to be investigated.

A. G. Gillaspie, Jr. of the United States Department of Agriculture’s Agricultural Research Service (USDA-ARS) reports on a “New Method for Screening Cowpea Germ Plasm for Resistance to Cucumber mosaic virus” in the latest issue of Plant Disease. Gillaspie screened 350 cowpea lines from a core collection maintained by the National Plant Germplasm System (NPGS).

To select for CMV-resistant lines, Gillaspie inoculated freeze-dried cowpea tissue with the virus. He employed several assessment methods to measure virus buildup in the infected plants. The candidate lines were subsequently tested in greenhouse and field conditions to confirm resistance. Four CMV resistant lines, as well as four other lines with possible BlCMV resistance, were identified.

Subscribers to Plant Disease can read the complete article at http://www.apsnet.org/pd/search/2006/PD-90-0611.asp.