2个水稻温敏感叶色突变体的光合特性研究

为了探究水稻突变体表观与其生理特征之间的相关性与联系，利用经60Co-γ射线辐射的粳稻品种‘嘉花1号’后代中的2个温敏感叶色突变体mr21和mr06作为研究对象，分别对其苗期的叶色、叶绿素含量、荧光特性和叶绿体超微结构进行研究。结果表明，突变体mr21在20℃条件下生长时幼苗表现为黄色，32℃高温时呈绿色；与之相反，突变体mr06在20℃时为正常绿色，而在高温时为白化；电镜观察结果表明低温下的mr21和高温下的mr06的叶绿体结构发育不完全，与其叶绿素含量和叶绿体与叶色变化相一致。光合作用参数研究表明无论低温还是高温的2个突变体的Fv/Fm，ΦPSⅡ值均低于其野生型对照，这说明突变体的光能捕捉效率和转换效率都有所降低，进一步快速光曲线分析表明，2个突变体及野生型之间对光强的响应能力具有特异性。

Characteristics of Photosynthesis in Two Thermo-sensitive Leaf-color Mutants in Rice (Oryza sativa L.)

In order to explore correlation between rice mutants’phenotypes and physiological characteristics,we used two thermo-sensitive leaf-color mutants,mr21 and mr06,in rice derived from the same progeny of a rice japonica variety,’Jiahua 1’,treated by 60Co-γ radiation were used to investigate the leaf-color,chlorophyll content,their photosynthesis parameters and ultra-structure of chloroplast.Resultantly,under low temperature（20℃）,the leaf color of mr21 was yellow and turned green at 32℃,conversely mr06 was green at 20℃ and white at 32℃.Compared with their wild-type parent,’Jiahua 1’,the under-developed chloroplasts were observed in mr06 under high temperature（32℃） and in mr21 under low temperature（20℃）,respectively,which were coincided with both leaf-color and chlorophyll content.In addition,regardless of low or high temperature,Fv/Fm and ΦPSⅡ in the two mutants were lower than wild-type parent,which showed that the capture light energy efficiency and conversion efficiency in the two mutants were reduced.Rapid light curves analysis further showed that there are differences between mutant and wild type on the response ability of the light intensity.