Field performance of cowpea genotypes grown under virus pressure in Puerto Rico

Abstract

Cowpea [Vigna unguiculata (L.) Walp] is an important grain legume in many regions of the tropics. However, viral diseases, particularly Cucumber mosaic virus (CMV) and Blackeye cowpea mosaic virus (BlCMV), can be a limiting factor in cowpea production. We evaluated under virus pressure the performance of four PI’s (441917, 441919, 612607, 180014) and a commercial cultivar (Coronet), in Puerto Rico during 2007-2008. Viral infection of plants with BlCMV and CMV in these experiments occurred naturally through insect vectors from mechanically inoculated spreader-row plants, as determined by direct antigen-coated enzyme-linked immunosorbent assay (DACELISA). PI441917 had the highest grain yield (3682.8 kg ha^-1) among all genotypes except for the virus resistant control PI 612607, which was not significantly different. PI’s 180014 and 612607 had the highest seed protein concentration. The cultivar Coronet attained midbloom and maturity earlier than the other genotypes. These results confirm previous studies which showed that PI 441917 is an excellent yielder when plants are grown under virus pressure. This accession should be useful in cowpea breeding programmes to help control yield loses by CMV and BlCMV.

Key Words: Blackeye cowpea mosaic virus, Vigna unguiculata