分子标记辅助选择籼型直立恢复系

Molecular Markers-assisted Selection of Restorer Line of Dense and Erect Panicle

直立型密穗基因是水稻中与株型密切相关的基因,对作物高产分子育种有重要应用价值。为了培育直立密穗型的籼稻新品种,本研究以优良籼稻品种东南恢602(弯穗型)做母本,具有直立型密穗基因的近等基因系DW135为父本配置杂交组合。根据直立型密穗基因dep1在第5外显子上碱基缺失,筛选出一个插入缺失长度多态性(Insertion deletion length polymorphism,InDe1)位点,设计合成插入缺失(InDel)标记,该标记能准确检测含或不含dep1基因的纯合基因型和杂合基因型品种。利用该标记对回交群体进行辅助选择,筛选含有dep1基因的纯合株系,成熟后对穗部性状的调查结果与分子标记检测结果基本一致。利用与目的基因共分离的分子标记,建立直立穗型分子标记辅助育种体系,为今后开展株型育种提供了理论依据和材料基础。

Dense and Erect Panicle （EP） gene was the one with great practice value related to plant type in rice varieties, leading to adramatic increase in crop yield. A new indica rice variety with erect panicle was obtained through the cross between the restorer line Dongnanhui602 as the female parent and near-isogenic line （NIL） rice variety DW135 with erect panicle controlled by the dep1 gene as male parent. According to the comparison of the DNA sequences between DEP1 gene and its dominant allelic gene dep1, 625 bases deletion occurred in exon 5. Thus, a insertion deletion length polymorphism （InDel） marker, which can identify the homozygous genotype and heterozygous genotype of dep1 gene, was designed and used for the assisted selection of dense and erect panicle in backcross populations. The result of the identification of panicle was completely coincident with that of marker assisted selection （MAS）. The utilization of the marker from dep1 gene was helpful not only for establishing a molecular marker assisted selection system of dense and erect panicle in rice, but also for providing theories and materials for the future new plant type breeding.