Development of a new japonica rice variety Nan-jing 46 with good eating quality by marker assisted selection | 通过分子标记辅助选择培育优良食味水稻新品种南粳46

Chino. 为培育食味品质优良、综合丰产性好的粳稻新品种,本研究以高产粳稻品种武香粳 14 作母本,以食味品质优良粳稻品种关东 194（含有控制低直链淀粉含量和暗胚乳的突变基因 Wx-mq）作父本配制杂交组合。通过比较 Wx-mq 与其位于第 6 染色体上的等位基因 Wx-b,Wx-a,wx 的 DNA 序列,发现 Wx-mq 基因的外显子 4 和外显子 5 上存在两个碱基突变,外显子 4 上的 G-A 突变产生了 NIaⅢ的酶切位点,并设计合成了能区分含或不含 Wx-mq 纯合基因型和杂合基因型的 CAPS 标记。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,筛选含 Wx-mq 纯合基因型的单株。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%。这样我们就成功培育了食味品质优良、综合丰产性好的粳稻新品种南粳 46。[著者文摘]

Inglés. In order to developing a new japonica rice variety with both good eating quality and high yield,we employed the high yield japonica rice ＂Wu-xiang-jing 14＂as the maternal parent was crossed to the good quality japonica rice＂Kantou 194＂with low-amylose content and translucent endosperm controlled by Wx-mq.By comparing the DNA sequence of Wx-mq gene and its allelic genes Wx-b,Wx-a,wx in chromosome 6,two mutated bases occurring in exon 4 and exon 5 were found in Wx-mq.The change of G-A in exon 4 just produced a recognition site for NIaⅢ digestion,so a cleaved amplified polymorphic sequences （CAPS） marker was designed,which could identify the Wx-mq homozygous genotype and heterozygous genotype.This marker was used for marker assisted selection （MAS） of low amylose content in F5and F6 lines derived from the combination of Wu-xiang-jing 14/Kantou 194.The investigation result of endosperm appearance was completely coincident with that of molecular detection,and the efficiency of MAS with the CAPS marker was up to 100%.As a result,＂Nan-jing 46＂,a new japonica rice variety with good eating quality and high yield,was successfully developed.