水稻黄叶突变体ys94的鉴定与基因定位

Identification and Gene Mapping of a Yellow-Leaf Rice Mutant ys94

水稻突变体ys94,是一个来源于化学诱变的叶色突变体。突变体在三叶期前出现明显的黄叶表型,叶绿素a、叶绿素b含量下降;透射电镜观察表明,突变体叶片叶绿体数量减少、类囊体片层退化。三叶期后叶色开始转绿。成熟期突变体ys94的分蘖数减少,但在结实率和株高等性状上与野生型相比并无明显差异。遗传分析表明,ys94的突变性状由一对隐性核基因控制。利用ys94×DJY组合的F_2定位群体,将突变基因定位在第8染色体短臂标记M8-3和M8-24之间,两标记间的物理距离为140kb,此区间包含11个候选基因。本研究结果为候选基因的克隆和功能分析奠定了基础。

A yellow-leaf mutant ys94 was isolated by chemical mutagenesis. Compared with its wild type, ys94 mutant displayed yellow leaf phenotype and reduced contents of both chlorophyll a and chlorophyll b in the germination period. The results of electron microscopic observation revealed that there were significantly reduced number of chloroplast,chloroplast dysplasia and degenerated thylakoid lamella in the ys94 in compared to WT.The tiller number of the mutant was reduced,but the plant height,the number of spikelets per panicle and the seed setting had no significant difference with the wild type. Genetic analysis showed that the mutation of ys94 was controlled by one recessive nuclear gene. Map-based mapping of the mutant gene was conducted by using of the F2 population from ys94 ×DJY. The mutant gene was finally mapped to a 140 kb region between the maker M8-3 and M8-24 on the short arm of chromosome 8, in which there were 11 annotated genes. Our study results have set a foundation for future cloning and functional analysis of the gene.