A stripe leaf mutant, temporarily designated st(t), was discovered in the progeny of the indica restorer Jinhui 10 treated with ethyl methane sulfonate (EMS). This mutant displayed the variegated leaves at three-leaf stage, and the variegation developed the white irregular stripe from elongation to maturity. Compared with the wild type, the mutant decreased the chlorophyll content and increased the carotenoid content significantly. Transmission electronic microscope (TEM) observation of cell structures indicated that there was no difference between the wild type and the green part of the mutant, and both of them developed normal chloroplast. In the white part of st(t), cell development was abnormal including irregular stromal lamellae, aberrant thylakoids, and more osmiophilic granules. Genetic analysis suggested that the mutational character was controlled by a recessive nuclear gene. An F 2 population (1500 plants) derived from the cross between Xinong 1A and st(t) was constructed to map this gene, and simple sequence repeats (SSRs) RM19745 and RM19762 on chromosome 6 were determined as the flanking markers for St(t). The genetic distances between St(t) and the 2 markers were 0.07 cM and 0.27 cM, respectively. Based on the genomic sequence map of 9311, the physical distance of St(t) was estimated to be 345 kb. This result provides a basis for map-based cloning of St(t) gene and molecular marker-assisted breeding. 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1500株西农1A/ st( t)的F 2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。