Abstract

                                Pollen grains and dry dormant seeds of two varieties of castor wore irradiated with X-rays at different doses. Roduction in germination and number of racemes per plant were noticed in R C 1377. No marked decrease in survival of seedlings, reduction in flowering duration, height of plant and number of primary branches per plant in both the varieties of pollen and seed irradiations were noticed in the M, generation. A greater inhibition of ger- mination was noted in seed irradiations in the two varieties in the My generation. Increase in height was recorded in pollen and seed irradiations in the two varieties. Reduction in R C 1377 and increase in NPH 1 In respect of the number of primary branches was registered in pollen as well as seed irradiations. In respect of the length of main raceme increase in RC 1377 and decrease in NPH 1 of pollen and seed irradiations was noticed. The num- ber of racemes per plant increased in both the varieties in pollen irradiation The doses employed in the present investigation can not be considered as high enough in the case of seed irradiation.

Key words :