水稻光敏核不育系HN5s不育性的遗传分析

Genetic Analysis on the Sterility in Indica PGMRs HN5s

利用 Co6 0 - γ辐照与 Na N3(Sodium azide)复合处理及成熟胚培养的方法 ,诱发不育性稳定的籼型光敏核不育系HN5 s产生可育突变体 ,通过不同突变体的自交 ,相互杂交及其与 HN5 s测交 ,并在人工控制光温条件下鉴定不育性 ,研究 HN5 s不育性的遗传。结果显示 :在人工诱变的条件下 ,HN5 s可以产生育性恢复和长日高温不育而长日低温可育两类可育突变体 ,HN5 s的不育性受两对隐性核基因控制 ,其中一对不育基因的作用较强 ,另一不育基因的作用较弱。当作用强的不育基因突变为作用弱的不育基因时 ,光敏不育系转变为温敏不育系。推断光敏核不育性的稳定性与不育系 (或品种 )对自然诱变因素的敏感性有关。

We obtained the two kinds of fertile mutants from the offsprings of the induced HN5s with the method of the combined treatment of the Co 60 γ irradiation, NaN 3(Sodium azide) and mature embryo culture. The one is the fertile revertant under the natural length day, high and low temperature. The other one is the male sterile under the natural length day, high temperature while is fertile revertant under the control length day, low temperature. To study the genetic behavior of male sterility in the Photoperiod Sensitive Genic Male Sterile Rice (PGMRs) line HN5s by utilizing the fertile revertants, we made the revertants self pollenated, test cross between the HN5s and its fertile mutants and identified the male sterility of the offsprings of the crosses and self pollenates under the control photo thermal conditions It was showed that the male sterility in HN5s was due to the two pairs recessive allele, a pair of male sterile gene with strength express and a pair of male sterile gene with weak express. When the strength express male sterile gene was induced into the weak express male sterile gene, the PGMRs was changed into Thermal Sensitive Genic Male Sterile Rice (TGMRs). The stability of the male sterility of PGMRs was related with the sensitive of the male sterile to the mutagenic factor. In addition, this paper stresses on the question of the causes of the undulation in male sterility of PGMRs and how to breed a stable PGMRs.