辐照蚕豆成熟花粉的细胞学效应

CYTOLOGICAL EFFECT OF γ RADIATION ON vicia faba POLLEN

To study the radiation cytological effect on pollen grain function, fresh pollen samples shed from Vicia faba were exposed to 60 Co γ ray in doses ranging from 0 to 837 Gy,and immediately permitted to germinate in vitro. It was shown that with increasing dose of γ irradiation, both the rate of pollen germination and the rate of sperm nucleus that migrating into pollen tube were reduced, concurrently, the rate of aberrant nuclei was elevated. Cytological examination showed that formation of the nuclei and organella in the pollen tube appeared to be normal by irradiation of 93 Gy, while with γ radiation of 279 Gy and up subcellular structure of the germinating pollen cells exhibited various degrees of distortion: mitochondria and immature plastids vacuolated, nuclear membrance disrupted, sperm nucleus fractured, occasionally, and photo chemoferritin accumulated in the immature plastids. With the doses of above 465Gy, multivesicular bodies presented in the pollen tube, suggesting that 465 Gy could be marked as the semilethal dose.