水稻条斑花叶突变体生态st(t) 的鉴定与遗传定位

利用EMS诱变育成优良籼型恢复系缙恢10号，从其后代中鉴定出一个白色条斑花叶突变体st(t)，在三叶期开始表现白斑，拔节期白斑变为不规则线状，一直保持到成熟。突变体叶绿素含量明显下降，类胡萝卜素含量显著升高。透射电镜观察表明，突变体的绿色叶片部位与野生型相比，在细胞结构上无明显差异，叶绿体发育正常；突变体的白化部位细胞结构异常，质体内多含有积聚在一起的嗜锇小球，不能发育出正常叶绿体所具有的类囊体和基质片层结构。遗传分析表明该性状受一对隐性核基因调控，利用1 500株西农1A/st(t)的F₂隐性定位群体，最终把St(t)基因定位在第6染色体SSR标记RM19745和RM19762之间，遗传距离分别为0.07 cM和0.27 cM，根据9311基因组序列推测，两标记之间的物理距离约为345 kb。这为St(t)基因的图位克隆和分子标记辅助育种奠定了基础。

Identification and Molecular Mapping of Stripe Leaf Mutant st(t) in Rice (Oryza sativa L.)

A stripe leaf mutant temporarily designated as st(t) was discovered in the progeny of an excellent indica restorer line Jinhui10 seed by treatment of EMS (ethyl methane sulfonate) in Rice Research Institute of Southwest University. The st(t) mutant displayed the variegated leaves at three-leaf stage, the variegation developed the white irregular line stripe from elongating stage to the maturation. Compared with the wild type, the mutant decreased the chlorophyll content and increased the carotenoid content ...