Abstract: A new japonica rice variety with good eating quality and high yield was obtained through the cross between high yield japonica rice variety Wuxiangjing 14 as the female parent and good quality japonica rice variety Kantou 194 with low amylose content and translucent endosperm controlled by the Wxmq gene as male parent. According to the comparison of the DNA sequences between Wxmq gene and its allelic gene Wxb, Wxa and wx, two mutated bases occurred in exon 4 and exon 5 were only found in Wxmq, and the change of GA in exon 4 just produced a recognition site for NIaⅢ digestion. Thus, a cleaved amplified polymorphic sequence (CAPS) marker, which can identify the homozygous genotype and heterozygous genotype of Wxmq gene, was designed and used for the assisted selection of low amylose content in F5 and F6 lines derived from Wuxiangjing 14/Kantou 194. The result of the identification of endosperm was completely coincident with that of marker assisted selection (MAS). And the efficiency of MAS with the CAPS marker was up to 100%. As a result, Nanjing 46, a new japonica rice variety with good eating quality and high yield, was successfully developed by pyramiding Wxmq gene and high yield genes.

Key words: marker assisted selection, eating quality, rice, cleaved amplified polymorphic sequence, breeding

摘要： 为了培育食味品质优良、综合丰产性好的粳稻新品种，以高产粳稻品种武香粳14作母本，具有暗胚乳突变基因的优质粳稻品种关东194作父本配制杂交组合。利用与暗胚乳突变基因Wxmq直接相关的单核苷酸差异，设计合成了CAPS标记，该标记能区分含或不含Wxmq基因的纯合基因型和杂合基因型。利用该标记对武香粳14/关东194衍生的F5、F6株系进行辅助选择，筛选到含Wxmq基因的纯合基因型，成熟后对胚乳淀粉性质的调查结果与分子检测结果完全一致，分子标记辅助选择效果达100%。最终将关东194的暗胚乳突变基因Wxmq与高产基因聚合于一体，育成含有暗胚乳突变基因Wxmq的优良食味粳稻新品种南粳46。

关键词: 分子标记辅助选择, 食味品质, 水稻, 酶切扩增多态性序列, 育种