水稻红莲型CMS育性恢复QTL分析

红莲型CMS是在我国杂交水稻生产中被广泛利用的雄性不育细胞质之一。为了同时定位红莲型CMS育性恢复主效和微效QTL，利用红莲型CMS不育系粤泰A(YTA)与“Lemont／特青”RIL群体测交，结合1张含有198个DNA分子标记的高密度遗传图谱，对测交F1群体的小穗育性和花粉育性进行复合区间作图。在对YTA的育性恢复性方面，该。RIL群体的2个亲本之间具有明显差异，特青的恢复性较强，其测交F1的小穗育性和花粉育性分别为72％和51％；而Lemont测交F1的小穗育性和花粉育性分别为32％和9％。复合区间作图定位到4个育性恢复QTL，分别位于水稻第1、2和10号染色体上，单个QTL的贡献率在5％～24％之间。其中，除1个QTL的增效基因来源于Lemont外，其余3个QTL的增效基因均来源于特青。效应最大的QTL为qRF-10-1，该QTL位于10号染色体RM258-C16标记区间，对小穗育性表型变异的贡献率为24％，对花粉育性的贡献率为17％，且该QTL被检测到的LOD值显著较高，因此是1个主效QTL，其增效基因来源于特青。除了主效QTLqRF-10-1外，其它3个QTL对性状的贡献率均在10％以下(5％～8％)。由此表明，该RIL群体对红莲型CMS的育性恢复由1个主效QTL控制，并受其它几个微效QTL的影响。该QTL定位结果与小穗育性在测交F1群体中呈连续的双峰分布的结果相一致。与主效QTL qRF-10-1紧密连锁的SSR标记为RM258，该主效QTL可作为分子标记辅助育种的操作目标之一，用于杂交稻分子育种中培育红莲型CMS的强恢复系。

Mapping of QTL for Fertility Restoration of HL-type Cytoplasmic Male Sterility in Rice (Oryza sativa L.)

Honglian-type CMS (CMS-HL) is one of the most extensively used cytoplasms in hybrid rice of China. In order to map both major and minor QTL controlling fertility restoration for CMS-HL,a Honglian-type male sterility line (YTA) was test-crossed to the RILs derived from a cross between Lemont and Teqing.Composite interval mapping was conducted based on the data of spikelet fertility and pollen fertility in the test-cross population of YTA/RILs.Significant difference between the two parents Lemont and Teqing in fertility restoration was observed and Teqing showed a much stronger fertility restoration than Lemont.Totally, four QTL for spikelet fertility and pollen fertility were mapped to chromosomes 1,2 and 10 of all the twelve rice chromosomes,each explaining 5%-24% of the trait variation.Among these QTL,three QTL with their positive alleles were from the parent Teqing.QTL qRF-10-1,mapped onto the interval RM258-C16 of chromosome 10,produced the largest effects on both the two traits,accounting for 24% of the spikelet fertility variation and 17% of the pollen fertility variation.Comparatively, the other three QTL produced much small effects on the traits,each explaining less than 10% of the trait variation. These results indicated that the fertility restoration of the RILs was mainly controlled by the major QTL qRF-10-1 and was also modified by the other three minor QTL.This suggestion was further confirmed by the continuous binary frequency distribution of spikelet fertility in the test-cross population of YTA/RILs.QTL qRF-10-1 with the most closely linked SSR marker of RM258 could be used as a target to be manipulated in breeding restoration lines for HL-CMS.