玉米F_2群体分子标记偏分离的遗传分析  

Genetic Analysis of Segregation Distortion of Molecular Markers in Maize F_2 P opulation

作　　者：严建兵[1] 汤华[1] 黄益勤[1] 郑用琏[1] 李建生[1] 

机构地区：[1]华中农业大学作物遗传改良国家重点实验室,武汉430070

出　　处：《Acta Genetica Sinica》2003年第10期913-918,共6页

基　　金：国家自然科学基金重大项目 (3 9893 3 5 0 );国家重大基础研究项目 (2 0 0 1CB10 880 1)资助~~

摘　　要：以优良玉米杂交组合 (综 3× 87 1)的F2 群体为材料 ,构建了包含 15 0个SSR标记和 2 4个RFLP标记的玉米分子标记连锁图。通过对 174个分子标记的分析 ,发现有 4 9个分子标记表现偏分离 (P <0 0 5 ) ,占总标记数的2 8 2 %。这些偏分离标记有 11个偏向父本综 3,占 2 2 5 % ;12个偏向母本 87 1,占 2 4 5 % ;2 5个偏向杂合体 ,占5 1 0 %。还有 1个标记同时偏向双亲。同时在 9条不同的染色体上发现 14个偏分离的热点区域 ,其中 4个与已经定位的配子体基因的位置相近 ,由此表明配子体基因是导致偏分离的部分原因。所发现的SDR6 1和SDR7 2似乎是两个新的偏分离热点区域。进一步讨论了引起偏分离的原因 ,以及偏分离标记对QTL定位的影响。对于单位点的QTL分析而言 ,偏分离标记一般不会影响QTL定位的位置和效应 ;对于两位点的上位性分析而言 。A genetic linkage map of maize was constructed us ing 150 SSR and 24 R FLP markers,with F 2 population from an elite hybrid (Zong3×87-1).Among 174 m arkers,covering whole maize 10 chromosomes,49 markers (28.1%) showed the geneti c distortion (P<0.05).Of the total segregation distortion markers,11 marke rs (22.5%) deviated toward male parent,Zong3,while 12 markers (24.5%) deviated toward female parent,87-1,besides 25 markers (51.0%) distorted to heterozygot e.Only one marker distorted to both parents.Totally,14 segregation distortion re gions (SDRs) were detected among 9 different chromosomes.Four of them were locat ed in near regions where gametophyte genes were mapped,indicating that segregati on distortion may be caused by gametophyte genes partially.Two segregation dist ortion regions,SDR6-1 and SDR7-1,detected in this study,seemed to be new segr egation distortion regions.In this paper,reasons for segregation distortion an d effects of segregation distortion on genetic mapping and QTL analysis were dis cussed.Regarding to QTL analysis with single locus,segregation distortion woul d not affect QTL mapping,but regarding to analysis of digenic interactions for epistasis,the fewer distortion markers and larger size population would be need ed.

关 键 词：玉米 偏分离 分子标记 

分 类 号：S513[农业科学—作物学]