水稻油菜素内酯不敏感且闭花授粉突变体的遗传分析和基因定位

Genetic analysis and mapping of a brassinosteroid insensitive and cleistogamy mutant in rice(Oryza sativa)

粳稻秀水09(XS09)经甲基磺酸乙酯(EMS)诱变处理,得到一个性状稳定的闭花授粉突变体fod(floret opening defective)。突变体fod与野生型XS09相比,具有植株相对矮小,种子相对短粗,授粉时内外稃不分离等特点。且该突变体对外源油菜素内酯不敏感,表现为突变体叶夹角在油菜素内酯处理后明显小于野生型;不同浓度油菜素内酯对突变体的根长抑制程度显著低于野生型;在黑暗培养下野生型的中胚轴伸长,而突变体没有。遗传分析表明fod突变性状受1对隐性基因控制。利用F2杂交群体,经SSR和STS分子标记将突变基因Osfod定位于第7号染色体标记P8与P9之间,两个标记之间的物理距离大约为296 kb。

A cleistogamy mutantfod （floret opening defective） was isolated by ethyl methane sulfonate （EMS） from a japonica rice cultivar Xiushui09 （XS09）. Compared with the wild type XS09, the mutant fod showed reduced plant height, round seeds and closed spikelets. Physiological experiments showed that the mutant fod was insensitive to the exogenous brassinosteroid （BR）. Genetic analysis indicated that the phenotype of the mutant was controlled by a single re- cessive gene. The Osfod gene was mapped on the chromosome 7 between the mark P8 and P9, which was 296 kb in length.