籼稻恢复系昌恢891抗褐飞虱基因定位

摘要

Brown planthopper ( BPH) is one of the most serious insects in rice,and the host resistance has been recognized as one of the most effective measures for BPH management.At present,lots of rice materials associated with resistance to brown planthopper have been identified in China.The identification and location of the brown planthopper gene is the basis for the breeding of resistant rice cultivras. Changhui 891 is an indica rice cultivar with high resistance to BPH.To detect the QTL associated with BPH in Changhui 891,a genetic linkage map of a F2 population was constructed between Changhui 891 and a japonica cultivar 02428.The link⁃age map includes 108 simple sequence repeat ( SSR) markers and covers 2 038.6 cM of rice genome,with an average marker interval of 18.8 cM.One hundred and twenty nine plants of F2:3 families were constructed,and the QTL analysis of BPH resistance was conducted using composite interval mapping implemented in Windows QTL Cartographer 2.0 software by the F2:3 families,a major QTL,temporally named qBPH4(t),was detected between RM518 and RH007 on chromosome 4.The LOD score of qBPH4(t) was 10.53,and it could explain 39.8 % of total phenotypic variance,respectively.%褐飞虱是危害水稻生产最重要的虫害之一。培育抗褐飞虱水稻品种被认为是最有效的减少虫害的方法。目前，我国在栽培品种中陆续发现并鉴定了大量抗褐飞虱材料，而鉴定和定位抗褐飞虱基因是培育抗虫水稻的基础。昌恢891是一个优良的抗褐飞虱籼稻恢复系品种，为定位其中控制褐飞虱的基因，对亲本昌恢891，02428及其杂种Fl ，F2：3单株129个分离群体进行抗褐飞虱鉴定，结果表明该抗性性状由一对显性主效基因控制，并受到微效基因的修饰。利用昌恢891／02428 F2群体，构建了含有129个单株的F2群体的遗传连锁图谱。该连锁图包含108个SSR标记，覆盖整个水稻基因组2038．6 cM，每两个标记之间的平均距离为18．8 cM。利用Windows QTL Cartographer V2．0的复合区间作图法对F2群体的抗褐飞虱基因进行定位，在第4染色体上检测到一个主效抗性QTL位点，LOD值为10．53，贡献率分别为39．8％，位于第四染色体标记RM518和RH007之间，暂时命名为qBPH4（ t）。