一个新的水稻短根毛突变体的遗传分析和基因定位

根毛是植物吸收水分和养分的重要器官。本研究从T-DNA突变体库中获得一个以中花11为遗传背景的水稻短根毛突变体, 命名为ossrh3 (Oryza sativa short root hair 3)。该突变体的根毛伸长严重受阻, 并且伴随株高、主根长、侧根长和侧根数目等性状的改变。遗传分析表明该突变性状受1对隐性单基因控制, 利用ossrh3纯合体和籼稻品种Kasalath杂交构建F₂定位群体, 利用已公布的水稻SSR (simple sequence repeat)和自行设计的STS (sequence- tagged site)标记, 最终将OsSRH3定位在水稻第1染色体上的标记S38978和S39016之间, 物理距离约为37.7 kb, 包含8个候选基因, 为进一步克隆OsSRH3基因和研究禾本科作物根毛发育的分子调控机理提供了依据。

Genetic Analysis and Gene Mapping of a Novel Short Root Hair Mutant in Rice

In plants,root hair is important organ for the uptake of nutrients and water.A rice(Oryza sativa L.) mutant with short root hairs(ossrh3) was isolated from a T-DNA insertion mutant library with Zhonghua 11 background.The elongation of root hairs in the mutant was severely impaired,and other traits were also affected including the plant height,primary root length,lat-eral root length,and number of lateral roots.Genetic analysis indicated that the mutant phenotype was controlled by a single re-cessive nuclear gene.For mapping the OsSRH3 gene,an F2 population was generated by crossing the mutant ossrh3 with Kasalath wild type.Ultimately by using the published SSR(simple sequence repeat) markers and some newly designed STS(se-quence-tagged site) markers,the OsSRH3 locus was mapped to a 37.7 kb region between the markers S38978 and S39016 on chromosome 1.Within this region,there were eight predicted genes.This result will be helpful for the cloning of OsSRH3 and characterization of the molecular genetic mechanisms of root hair development in gramineous plants.