棉花遗传图谱构建及纤维品质性状的QTLs定位

Genetic Map Construction and QTLs Analysis of Fiber Quality in Cotton

为进一步增加特异性分子标记,填补棉花遗传图谱密度空隙,挖掘与纤维品质紧密相关的数量性状位点（QTLs）以陆地棉（Gossypium hirsutum L.）中棉所8号和海岛棉（Gossypium barbadense L.）Pima90杂交产生的F2群体为材料,利用SSR标记对构建棉花遗传图谱及纤维品质性状QTLs定位进行研究。结果表明：构建了包含15个连锁群和102个标记位点（其中25个标记位点前人未曾报道）的连锁图谱,图谱总长642.1cM,约占棉花基因组的14.4%,标记间平均距离为6.3cM。15个连锁群中的6个分别被定位于5条染色体上,9个连锁群未定位于染色体上。应用复合区间作图法分析F2单株和F2∶3家系的纤维品质性状,检测到11个与纤维品质有关的QTLs,包括2个纤维长度（FL）,4个马克隆值（FM）,3个比强度（FS）,2个伸长率（FE）,分别解释表型变异的19.1%~24.8%、8.9%~16.9%、11.8%~19.0%和12.2%~34.3%。

In order to increase the linkage map markers of cotton,so as to fill the gap of genetic map density,and detect the QTLs related to fiber qualities,An F2 population from a cross between CRI 8 （Gossypium hirsutum）and Pima 90 （Gossypium barbadense ）was used to construct the linkage map with simple sequence repeat （SSR）.Results：This map included 102 markers distributing on 15 linkage groups （25 markers is not reported）,covering 642.1cM,accounting for 14.4% of the cotton genome,and with an average distance of 6.3 cM between two markers.six out of 15 linkage groups were located on five chromosomes,and nine linkage groups were not located on any chromosomes.The fiber quality of the F2 plants and the F2∶3 family lines were analyzed by composite interval mapping and 11 quantitative trait loci of fiber quality were identified in the genetic map and these traits involved the QTLs of two fiber lengths, four fiber micronaires,three fiber strengths,two fiber elongations.The QTLs separately explained 19.1%~24.8%,8.9%~16.9%,11.8%~19.0% and 12.2%~34.3% of the phenotypic variations in the four traits.