一个辐射诱变的水稻卷叶突变体的特性研究

Characterization of a ^(60)Co-γ Mutated Rolled-leaf Mutant in Rice

通过60Co-γ射线处理籼稻品种青华占的干种子,获得一个稳定遗传的卷叶突变体(γ-rl),对其进行叶片细胞学观察、根形态特性分析及生长素(IAA)和色胺含量的分析。结果显示卷叶突变体γ-rl叶片的中脉面积比野生型增加,而侧脉数目减少;突变体种子萌发后幼苗的主根长度比野生型显著缩短,根总数也显著减少,表明幼苗期γ-rl的根系发育明显差于野生型;突变体γ-rl幼苗的主根生长对外源IAA、IAA抑制剂NPA处理的反应与野生型相比也存在显著差异;在幼苗期,突变体γ-rl叶片内源IAA的含量明显低于野生型,而色胺的含量明显高于野生型,但在抽穗期,突变体γ-rl叶片的IAA和色胺含量与野生型相比均无显著差异。研究结果将为阐明该突变体卷叶突变产生的原因及卷叶相关基因(OsFMO(t))的功能打下基础。

Dry seeds of an indica rice cultivar Qinghuazhan（ QHZ）,were mutagenized by60Co γ- rays radiation,and a rolled-leaf mutant,named γ- rl was obtained and the mutation phenotype was stably inherited. Cytological observation of leaves,characterization of roots morphology and auxin（ IAA） and tryptamine content determination were conducted in this study. The results showed that the midrib areas increased and the lateral vein number reduced in γ- rl as compared to the wild type,QHZ; the taproot length of the seedlings of γ- rl was significantly shorter than that of QHZ after germination and the total root number significantly decreased; the responses of root growth to the treatment of exogenous IAA and NPA（ an inhibitor for IAA polar transportation） significantly different from the wild type; at the seedling stage the endogenous IAA content in γ- rl significantly decreased and the tryptamine content significantly increased as compared to QHZ,however,no significant differences of IAA and tryptamine content were found between γ- rl and QHZ at the heading stage. These results laid the foundation for elucidating the regulatory mechanisms of rolled-leaf and the functions of the rolled-leaf relative gene,OsFMO（ t）.