Mutation studies in cowpea

The effectiveness and efficiency of two mutagens, EMS and gamma rays was studied in VCM-8 variety of cowpea (Vigna unguiculata L. Walp.). For this purpose the seeds were treated with gamma rays and EMS, and to obtain the spectrum and frequency of chlorophyll mutations in M₂ generation were observed. The treatment with gamma rays was found to be more efficient than EMS to induce chlorophyll mutants. Progressive increase in mutation frequency of chlorophyll mutations was observed with increasing doses of gamma rays and EMS. Four types of chlorophyll mutants, such as, chlorine, albina, xantha and viridis were found to be induced due to the treatment with mutagens. The highest frequency of chlorophyll mutations (2.56) was reported due to the treatment with gamma rays (450 Gy). There was dose dependent increase in the spectrum and frequency of chlorophyll mutations.