The effects of maize pollen irradiation on the seed setting of F1M1 and the plant growing of subsequent generations

The irradiation effects were studied by the methods of exposing the pollen of maize hybrid (F1M1) to 60Co γ-ray and self-crossing in the F1M1 and subsequent generations. The results were as follows. The seed setting of F1M1 generation was severely affected after pollen was treated with a rather high dose (100 Gy), the ear bearing more scurfy seeds, alveolar-liked structures and less plump seeds. The difference between two treatments, (1) irradiating two inbred lines of one hybrid with two doses (100 and 50 Gy) separately, then pollinating with blended pollen, (2) irradiating with single dose, was not significant. Anther and (or) pollen-aborted plants appeared in F2M2 generation. The damage effects of irradiation still existed in F3M3 generation, several plants having mutant characters appeared, and the opportunity of breeding selection increased