利用F2-NIL定位一个控制水稻穗颖花数、株高和抽穗期的多效QTL  

Identification of One Pleiotropic QTL Controlling Three Traits of SPP, PH and HD Using F_2-NIL

作　　者：张玉山[1] NagabushanaNaidu 汪剑波[2] 徐才国[2] 

机构地区：[1]电子科技大学中山学院生物化学系,中山528402 [2]华中农业大学作物遗传改良国家重点实验室,武汉430070

出　　处：《吉林农业大学学报》2008年第3期246-251,共6页Journal of Jilin Agricultural University

基　　金：国家重点基础研究发展规划项目(G1998010200);电子科技大学中山学院博士启动基金项目

摘　　要：利用重组自交系合适世代（F7或F8）的单株具有一定杂合率的特点,在重组自交系的一个家系内,选择到水稻每穗颖花数（SPP）、株高（PH）和抽穗期（HD）3个性状同时分离的2个单株。以这2个单株为亲本快速构建F2群体（F2-NIL）。由于这2个单株背景高度一致,故这个群体就是快速构建的近等基因系群体。后代测验结果为3个数量性状中的每一个性状的3种基因型分离数目均相同（29,63,33）,且卡方测验符合1∶2∶1的孟德尔分离比例,表明3个数量性状——每穗颖花数、抽穗期和株高均表现为质量性状分离。利用这个群体定位了一个位于第8染色体上、同时控制水稻每穗颖花数、抽穗期和株高3个性状的多效区段RM310-RM126,这个QTL可以解释这3个性状的很大的表现型方差（66.0%-81.1%）。利用后代测验结果,定位了控制这3个性状的基因位置。控制3个性状的基因和QTL位于相同的位置,QTL遗传效应的方向也相同,表明控制3个性状的遗传机制更可能是一因多效的结果,而非3个紧密连锁基因单独控制的结果 同时也表明利用重组自交系群体构建近等基因系的方法是快速构建近等基因系的有效方法。Due to a certain extent of heterozygous ratio existing in proper generation of recombinant inbred lines（RILs）,in the present study,two plants,in which spikelets per panicle（SPP）,plant height（PH） and heading date（HD） were segregated simultaneously,were selected in one family of a recombinant inbred line.Using these two plants as parents,F2 population was constructed rapidly.Since the backgrounds of the two plants were significantly identical,this F2 population was near isogenic lines（NILs） constructed rapidly（F2-NILs）.Progeny test showed that any of the three traits had the same segregating numbers（29,63, 33） and these segregating numbers were in consistency with Mendelian inheritance ratios（1∶2∶1） by χ square test.This indicated that the segregation of the three quantitative traits became the segregation of qualitative traits.Using this population,one pleiotropic QTL controlling these three traits simultaneously was identified on chromosome 8,which was located in the interval RM310—RM126.This QTL could explain very large variances of these three traits（66.0%—81.1%）.The gene controlling these three traits was also located in the same position by using F2 progeny population.The positions of gene and QTL controlling the three traits were the same.And the directions of genetic effects of QTL were also the same.It indicated that the genetic mechanism of controlling the three traits might have been pleiotropic but not that the three tightly linked genes controlled the three traits respectively.The method based on RILs is a very effective method to construct NILs rapidly.

关 键 词：多效QTL 近等基因系 水稻 每穗颖花数 株高 抽穗期 

分 类 号：S511.032[农业科学—作物学]