~(60)Coγ射线辐照诱发创造水稻显性雄性核不育系

早籼品种浙 92 48干种子经 3 0 0Gy60 Co γ射线辐照后 ,M1代植株的育性大幅下降 ,并出现了完全不育株。选用浙 92 48M1高不育株再经人工去雄后与G93 89杂交 ,所得杂种M2 F1仍分离出雄性不育株。继续用浙 92 48回交 ,M3BC1 M6BC4群体中仍出现不育株与可育株 ,分离比为 1∶1。用早籼新品系浙辐 5 0 4、H41 6,中籼新品系长丝软占、玉占 ,三系杂交籼稻保持系辐南B、3 5 1B及恢复系IR3 6、2 0 964与BC2群体中的不育株杂交 ,所有杂交一代群体都出现不育株与可育株分离 ,比例接近 1∶1。此外 ,回交、杂交群体中分离出的可育株与不育株进行姐妹杂交 ,后代也按 1∶1分离出不育株与可育株。然而 ,所有可育株的后代 ,不管来自杂交、回交或是姐妹交 ,均未出现育性分离 ,表现正常可育。本实验所得的不育突变株及其衍生不育株的花药瘦小 ,花粉呈典败或圆败 ,自然结实率与套袋结实率很低。上述结果表明 ,诱发产生的不育系属显性雄性不育 ,由细胞核内单基因控制

INDUCTION OF DOMINANT MALE STERILITY BY USING 60 Co γ\| RAYS IRRADIATION IN RICE Oryza sativa L.

The fertility of M 1 plants, which developed from dried rice (c.v.Zhe9248) seeds treated with γ\|rays at the dosage of 300Gy, decreased dramatically, and some of the M 1 plants showed completely male sterile. There were still fertile and sterile plants in the M 2F 1 population of artificially emasculated high sterile Zhe9248 M 1 plants crossed to normal variety G93\|89, and consequently, Zhe9248 was back crossed to the sterile plants successively as recurrent parent. In all the above back cross populations, fertile and sterile plants segregated in a 1∶1 ratio. The M 4BC 2 male sterile plants were crossed to various rice materials, e.g. early season indica rice(Zhefu 504,H416), middle season indica rice (Chuan\|si\|ran\|zhan,Yu\|Zhan), maintainer lines(Fu\|Nan B,351 B) and restorer lines(IR36,20964). In all the above F 1 populations, male sterile and fertile plants again segregated in a 1∶1 ratio. In addition, sib\|crossing were made in the back crosses and hybrid crosses between male sterile and fertile plants, male sterile and fertile plants appeared in a similar fashion as in test crosses. However, no male sterile plants were recovered from fertile plants either of back crosses or test crosses. The anthers of male sterile plants appeared small and poorly developed, the pollen showed typical abortion or round abortion, the seed set in bagged panicles was very low. The experimental data showed that this male sterile rice mutant was inherited in a single\|gene mode.