Abstract

A study was conducted to screen some cowpea mutants for resistance to Maruca vitrata. Fifteen selected cowpea mutants, the parent ‘IT84S2246 D’ as a susceptible check and a resistant check ‘Tvu 946’ were used in an intensive free choice test. Potted plant samples were randomly placed in a large screen cage and infested with adult females of Maruca for seven days. The results showed that there was a significant variation in the level of resistance among plant types. Mutant 4 with a yield loss of 46.1% as compared with 75.1% of the parent was found to be moderately tolerant while others were susceptible to Marucainfestation. Seed yield was found to be significantly and negatively correlated with percent pod damage. Hence, percent pod damage could be used as an index of plant tolerance on the field.

Key words: Cowpea, mutants, Maruca pod borer, tolerance, choice test, screening.