水稻细胞质雄性不育性恢复突变的初步研究

Characterization of Fertility-restoring Mutants Isolated from Radiation Mutated Cytoplasmic Male Sterile Rice

利用２９０Ｇｙ６０Ｃｏ—γ射线处理细胞质雄性不育系Ⅱ—３２Ａ和协青早Ａ，获得了育性恢复突变体，突变频率分别为８×１０－３和５×１０－３。从Ⅱ—３２Ａ中所获得的育性恢复突变体，在农艺性状上与Ⅱ—３２Ｂ基本相同。已稳定的Ⅱ－３２Ａ育性恢复突变体Ⅱ－３２Ｒ，与Ⅱ－３２Ａ和珍汕９７Ａ测交，杂种结实率在７０％以上。对测交后代的遗传分析表明，Ⅱ—３２Ｒ对珍汕９７Ａ和Ⅱ—３２Ａ的育性恢复均涉及２对恢复基因、Ⅱ—３２Ｒ与珍汕９７Ａ和Ⅱ—３２Ａ的杂种Ｆ２代在结实率分布上存在差异，Ⅱ—３２Ａ／Ｔ—１８和Ⅱ—３２Ａ／Ｔ—２１具有相同的趋势，但珍汕９７Ａ／Ｔ—１８趋向低结实率端，Ｔ—１８和Ｔ—２１为Ⅱ—３２Ｒ—１和Ⅱ—３２Ｒ—２中选出的结实率较高的两株系。诱导不育系产生育性恢复突变体是获得细胞质雄性不育系恢源的一种有效方法。

Male fertile revertants from both cytoplasmic male sterile lines Ⅱ-32A and Xieqingzao A,Which have Indonisia paddy rice cytoplasm and WA (wild abortive) cytoplasm respectively, were obtained by treatment with 290 Gy 60Co-γ rays in frequencies of 8×10-3 for 1Ⅱ-32A and 5×10-3 for Xieqingzao A. The acquired riverments from Ⅱ-32A are similar to Ⅱ-32B in major characters. Test crosses of stabilized revertants Ⅱ-32R with Ⅱ-32A and Zhenshan 97A show normal seed setting rate in F1 hybrids. Genetic Analysis of the progenies of the tested crosses indicates that the fertility restoration of both zhenshan 97A and Ⅱ-32A by Ⅱ-32R involves two pairs of restoring genes. However, there exists difference in distribution of seed setting rate in Fxs between zhenshan 97A/Ⅱ-32R and Ⅱ-32A/Ⅱ-32R. Ⅱ-32A/T-18 and Ⅱ-32A/T-21 have the same distribution tendency,whereas Zhenshan 97A / T-18 biased toward low value. T-18,T-21 have higher seed setting rate, and selected from Ⅱ-32R-1 and Ⅱ-32R-2, respectively Development of fertility-restoring mutant by induced mutation could be used as an effective method to obtain restorer line of cytoplasmic male sterile line.