Abstract: A rice mutant ts-ua with righthanded helical stem at seedling and considerable tiller angles was screened from T-DNA inserted rice mutant pools.Moreover,the mutant showed dwarf,later heading and lower fertility than wild plants.The size of epidermis cells was different between nearside and starboard cells observed from the longitudinal section of twisted stems by histological sections.Genetic analysis showed that the mutant was controlled by a single recessive gene.The ts-ta mutant was not induced by T-DNA insertion though it was screened in T-DNA inserted mutant pools.Therefore,the mutant gene could not be isolated by T-DNA tagging method.

Key words: rice, twisted stem, dwarf, mutant, heading date, genetic analysis, characterization

摘要： 从6000个水稻TDNA插入突变体库中筛选到1个苗期茎秆呈螺旋生长，成株期株型松散，植株矮化，抽穗延迟的突变体tsta。取突变体弯曲的叶鞘做石蜡切片发现，突变体弯曲的叶鞘周围表皮细胞完整，但两侧细胞的大小不同。弯曲内侧细胞小，排列紧密，外侧细胞较内侧大。T1 、T2及回交结果表明，该突变体能稳定遗传且受一对隐性单基因控制，共分离分析表明该突变性状不是由于TDNA插入引起的，因此不能通过TDNA 标签法克隆该基因。

关键词: 水稻, 茎秆螺旋, 矮, 突变体, 抽穗期, 遗传分析, 特性鉴定