水稻生育前期叶绿素含量QTL分析

QTL Analysis for Leaf Chlorophyll Content at Early Growth Stage in Rice

采用Nipponbare(粳)/Kasalath(籼)//Nipponbare(粳)杂交衍生的98个株系所组成的回交重组自交系群体(backcross recombinant inbred lines,BILs)为试验材料,在生育前期(苗期-孕穗期),对水稻倒1叶和倒2叶的叶绿素含量进行数量性状基因位点(quantitative trait loci,QTL)分析,结果表明:共检测到12个非条件QTL和3个条件QTL,分布在第1,3,4,5,6和12号染色体上,单个QTL贡献率10.62%～34.41%之间。在苗期检测到的QTL位点相对较多,其中在第4号染色体上检测到一个从苗期到拔节期持续表达的QTL聚集区段,该区域的存在有利于提高水稻叶片叶绿素的含量,增强光合作用。比较分析条件与非条件QTL的表达时期和数量发现,控制叶绿素含量的QTL多分段表达,这些QTL将为进一步了解水稻叶绿素含量的遗传机制提供理论依据。

Quantitative trait loci （QTL） controlling rice chlorophyll content at early growth stage （Seedling- Booting stage） were analyzed by using backcross recombinant inbred lines （BILs）. The backcross recombinant inbred lines were derived from a cross between Nipponbare （l＇aponica） and Kasalath （indica）. Fifteen QTL were detected, including twelve unconditional and three conditional QTL, and they distributed on the 1,3,4,5,6 and 12 chromosomes, explained 10.62%-34.41% phenotypic variations. Relatively more of the sites detected at seedling stage, one cluster of chlorophyll content form seedling stage to jointing stage sustained expression was revealed on the chromosome 4, which may be beneficial for improving the leaf chlorophyll content, promoting the rice photosynthesis. Comparation of conditional QTL with unconditional QTL at expression period and quantity aspect, many of chlorophyll content QTL existed spatial and temporal expression characteristics. These QTLs information would help us to understand the genetic basis of chlorophyll content in more detail.