Present research carried out on the development of techniques of plant tissue culture, on the induction and selection of radiation mutation and on the evaluation of mutant germplasm of several important crops. Optimum dosage of radiation were investigated for induction of mutation and selection of mutant in field or in vitro culture. The optimum dosage of potato nodal stem was revealed the range of 30-50 Gy in in vitro cultured plants. Variation of such agronomic traits was observed as earliness, short culm, high yield and other promising characters derived from irradiated rice, soybean, perilla, potato and some other crops in field and in vitro culture. The rice mutants of 18 lines were selected from irradiated rice cultivars and 48 soybean mutants were selected for earliness, large seed size and 2,000 line of soybean and rice, perilla were evaluated for the preservation of germplasm. Influence of plant growth regulators on P-32 uptake was observed in Broccoli callus in vitro culture. (Author).