水稻早衰突变体els-t的表型鉴定与基因克隆  

Phenotypic identification and gene cloning of an early senescence mutant els-t in rice

作　　者：冯巍 周国强[1] 陈浩天 马伯军[1] 陈析丰[1] FENG Wei;ZHOU Guoqiang;CHEN Haotian;MA Bojun;CHEN Xifeng(College of Chemistry and Life Sciences,Zhejiang Normal University,Jinhua 321004,China)

机构地区：[1]浙江师范大学化学与生命科学学院,浙江金华321004

出　　处：《浙江师范大学学报（自然科学版）》2022年第3期329-335,共7页Journal of Zhejiang Normal University:Natural Sciences

基　　金：国家自然科学基金资助项目(31871605);浙江省自然科学基金资助项目(LD19C130001)。

摘　　要：为研究植物衰老分子机制,从籼稻镇恢084的辐射诱变库中筛选到一个早衰突变体els-t(early leaf senescence-temporary),测定了叶片暗处理下叶绿素降解速率与光照条件下净光合速率,调查统计其主要农艺性状;通过该突变体与粳稻日本晴杂交,构建了F_(2)分离群体,进行了遗传分析与基因精细定位,并对区间内的候选基因进行PCR测序.结果显示:els-t突变体在分蘖期开始出现叶片早衰,黑暗下其叶片叶绿素降解速率比野生型快,光照下叶片净光合速率比野生型低,其穗长、每穗粒数、结实率、千粒质量、单株产量等主要农艺性状也显著低于野生型,但是株高却没有显著差异;遗传分析和基因定位结果表明,该早衰表型受单个隐性基因控制,目的基因被精细定位在水稻第3号染色体的标记InDel3和InDel4之间,物理距离为48 kb,在定位区间内1个候选基因Os03g0265100(PLS2)缺失1个碱基A,发生移码突变从而导致其编码的蛋白缺失了272个氨基酸.水稻els-t是PLS2基因的一个新等位突变,且导致植株早衰、影响多项农艺性状,具有重要的生物功能,为水稻分子育种提供一定的借鉴.In order to study the molecular mechanism of plant senescence,an early leaf senescence mutant els-t(early leaf senescence-temporary)was screened from the radiation-mutagenesis library of indica rice variety Zhenhui 084,its degradation rate of chlorophyll under dark stress,net-photosynthetic ratio under light and the main agronomic traits were analyzed.An F_(2) population was built by crossing the els-t mutant with japonica rice variety Nipponbare,which was used for the genetic analysis and gene fine mapping,and the candidate genes were sequenced by PCR.The els-t mutant began to display early-leaf senescence at tillering stage.In the leaves of els-t mutant,the chlorophyll degradation under dark stress was faster than that of wild type,and net-photosynthetic rate under light condition was lower than that of wild type.The main agronomic traits els-t mutant,such as panicle length,grains per panicle,seed-setting rate,1000-grain weight and yield per plant were also significantly lower than those of wild type,but there was no significant difference in plant height.The results of genetic analysis and gene mapping showed that the early-senescence phenotype of els-t mutant was controlled by a single recessive gene,and the target gene was finely mapped into a 48 kb interval between markers InDel3 and InDel4 on chromosome 3 of rice.In the mapping region,a candidate gene Os03g0265100(PLS2)was found to be deleted a base A,resulted in a frame-shift mutation and loss of 272 amino acids in its encoded protein.The els-t was found to be a new allele mutation of PLS2 gene in rice,which could lead to early senescence and affects many agronomic traits.It had also important biological function,which could provide references for molecular breeding of rice.

关 键 词：水稻 早衰突变体 els-t 表型鉴定 基因定位克隆 

分 类 号：Q943.2[生物学—植物学]