γ射线和X射线对甘蓝型油菜小孢子胚状体再生的影响

Effects of γ-and X-ray on in vitro microspore embryogenesis in Brassica napus L.

采用60Co-γ射线辐照甘蓝型油菜初花期植株和X射线辐射甘蓝型油菜小孢子发育到单核晚期至二核早期的花蕾后,分离小孢子进行培养诱导胚状体和植株,探讨了适宜油菜小孢子诱变的剂量和诱变方法。结果表明,γ射线对油菜离体小孢子胚状体的发生和发育均有很大的抑制作用,15Gy和40Gy处理平均每花蕾小孢子的产胚量分别是0.574和0.268个,40Gy可作为小孢子诱变的参照剂量。X射线对4个基因型离体小孢子胚状体再生也有影响,40Gy处理平均每蕾小孢子产胚4.086个,80Gy处理为0.834个,120～200Gy处理下降到0.021～0.019个,120Gy以上的处理剂量严重阻碍了小孢子胚的发生。采用X射线80～120Gy较适宜油菜小孢子诱变。

s: The plants of Line A10 at first flowering phase were irradiated by^(60)Co γ-ray of 15～400Gy at dose rate of 1 Gy/min and the buds containing late uninucleate spores from 4 lines (808, 813, 916 and Jia-3) were irradiated using X-ray with the doses of 40～200Gy at dose rate of 51.7Gy/min. Soon microspores were isolated and cultured so as to study the response of in vitro microspores to γ-and X-ray and ascertain optimal mutagen dose. Results showed that γ-ray inhibited microspore embryogenesis and embryoid development. In the treatments of 15Gy and 40Gy of γ-ray, mean embryo yield per bud was 0.574 and 0.268 respectively, the non-treated control was 0.670. The data suggest that 40Gy of γ-ray was suitable for irradiating microspores of B.napus. In the experiments of irradiated buds from 4 lines by X-ray, average embryo yield per bud was 4.086, 0.834 and 0.021 using 40, 80 and 120Gy. This indicates that 80～120Gy of X-ray might be better used for microspore mutation.