Effect of mutagenesis on germination, plant survival and pollen sterility in M₁ generation of in cowpea [Vigna unguiculata (L.) Walp]

M₁ generation of cowpea [Vigna unguiculata (L) Walp] was raised by treating the dormant seeds were studied in the two genotype of cowpea variety Pusakomal and V-240(Rambha). With varied concentration of gamma rays (Gy), Ethyl methane sulphate (EMS) and their combined treatments(Gy+ EMS). The mutagenic treatments seeds were tested for lethal dose 50% for all mutagens, separately and the dose at which 50% of the seed germination was considered as LD₅₀ values. Gamma rays, EMS and combined mutagens are produced a high frequency as well as a wide 50% spectrum of mutation. The frequency of mutation was more in combined treatments than gamma rays and EMS. The mutagenic effectiveness and efficiency was calculated based on biological damage. In M₁ generation based on seed lethality (L) and seedling injury (I) and M₂ generation was carefully screened for various chlorophyll and viable mutations. Mutagenic effectiveness and efficiency increased with the decreased in dose or concentration. In the present study EMS was provided to be more effective and efficient in causing mutations as compared to gamma rays and the combined treatments. A dose dependant decrease was noticed in most of the characters in M₁ generation. The results indicated that the reduction in germination present over control was noticed in all mutagenic treatments in both the cultivars, while increased pollen sterility was associated with corresponding increases in dose per concentration of mutagens. Results indicated that higher doses were more effective.