DETERMINATION OF THE RESISTANCE OF EARLY GENERATIONS OF Vigna unguiculata BEAN TO THE SEVERE MOSAIC VIRUS OF THE COWPEA, PANAMA.

Abstract

The Cowpea Severe Mosaic Virus (CpSMV) is a limiting factor in obtaining a significant yield of cowpea in Panama. To obtain resistant varieties to this virus and the Black Eye Cowpea Mosaic Virus (B1CpCW), crossing of brazilian varieties resistant to both viruses were performed. These crosses were evaluated in the field to the S₃ generation. The evaluation continued in the laboratory inoculating the first true leaves of generation S₄ with sap from infected plants with CpSMV. Susceptible selected material to this virus showed symptoms of infection a week after. Asymptomatic infections were discarded using serological tests. Of 382 breeding lines evaluated in the laboratory 134 (35.08%) were resistant to CpSMV. This number of resistant lines look promising to obtain resistant cowpea varieties to solve the yield problem caused by tis virus.