辐照花粉对小麦与中间偃麦草杂交及其胚胎发育的影响

EFFECT OF POLLEN IRRADIATION ON HYBRIDIZATION OF WHEAT AND Eltrigia Intermedia AND THEIR EMBRYO DEVELOPMENT

用γ射线辐照中间偃麦草散粉期的穗,用其花粉授予普通小麦'J-11'和'中国春',研究不同剂量辐照花粉对普通小麦与中间偃麦草杂交结实率、杂交种子含胚率、杂种幼胚培养和杂种幼苗获得率的影响.结果表明,5～9Gy低剂量γ射线略提高了中国春×中间偃麦草的结实率,表现出低剂量辐射的刺激效应,但对J-11×中间偃麦草却未表现出刺激效应.所有剂量的辐射对杂种幼胚均有伤害作用,杂交种子含胚率、杂种幼胚成苗率随剂量增加而下降.30Gy处理时有12.9%～14.5%的杂种幼胚发育成了植株,但该剂量应用到小麦中难以获得后代.在50～100Gy高剂量γ射线处理杂交种子胚发育不良,通过幼胚培养未能得到植株.将花粉辐照技术与幼胚拯救技术、花药培养技术有效结合,可以快速获得突变体,提高诱变育种效率.

Spikes of Eltrigia intermedia were radiated with 5 ～ 100Gy γ-ray during anthesis, and then their pollens were collected to pollinate to the common wheat “J-11” and “Chinese Spring”. The effects of pollen irradiation on the seed setting, embryo development, embryo culture and plantlet rate were studied. The results showed that low dose （5 ～ 9Gy） of irradiation enhanced the seed setting for Chinese spring× E. intermedia, but no such effect for J-11 ×E. intermedia. Irradiation with all doses damaged embryo development, percentage of seeds with embryos; rate of immature hybrid embryos developing into plantlets decreases with the increased doses. Percentage of seeds with abnormal embryos increased significantly with the doses. 12.9% ～ 14.5% of embryos could develop into plants in 30Gy treatment, which seldom occur to wheat. Embryos in 50Gy ～ 100Gy treatments were affected so serious that even none of them could develop into plants in vitro culture. It may be an effective approach to obtaining more mutants and enhancing induced mutation breeding by using combination of pollen irradiation, immature embryo rescue and anther culture of the resultant progenies.