Evaluation of cowpea varieties/genotypes against root rot incited by Rhizoctonia bataticola

Abstract

Cowpea [Vigna unguiculata (L.) Walp] (diploid, 2n=22) is an annual legume crop. Cowpea is a member of family Fabaceae. Cowpea is attacked by viruses, bacteria and fungi which causes many diseases. Root rot caused by Rhizoctonia bataticola (Taub.) Butler [Macrophomina phaseolina (Tassi.) Goid] is considered as one of the most serious diseases of cowpea. The characteristic symptom of root rot is leaf yellowing, followed by defoliation within two to three days. The infected stems and leaves become dry, brittle and straw colored. The plants show wilting and necrosis symptoms resulting from the pathogen’s vascular bundles blockage and secretion of toxic substances. Fifteen varieties/genotypes of cowpea received from RARI, Durgapura were evaluated against root rot under field condition during kharif 2023. The screening and varieties/genotypes were maintained under field condition with Randomized Block Design (RBD) and observations were recorded in which None of these were found immune or resistant to root rot. CSP 23-10, CPP 22-18, CPP 22-9, CPP 22-8 were observed susceptible, CPP 22-10, CPP 23-4, CPP 22-21, CPP 22-20, CPP 22-3 were found moderately susceptible, CPP 22-5, CPP 22-11, CPP 22-15, CPP 22-12, CPP 22-2, CPP 22-13 were observed moderately resistant and local cultivar (Check) were found highly susceptible.