摘要
利用筛选获得的18对具有双亲差异且在各世代群体中扩增效果稳定的SSR引物对芝麻RIL构建过程中的F1~F10群体的遗传差异进行跟踪检测。结果表明,随着RIL群体的不断加代,群体的DNA多态性带比率从F2的87.54%不断下降到F10的3.33%,杂合位点率从F1的100%不断下降到F10的0.19%,遗传相似性系数从F2的0.6669不断增加到F10的0.9908,遗传距离从F2的0.2592不断减小到F10的0.0094。从F2~F6,多态性带比率、杂合位点率、遗传相似性系数和遗传距离的变化幅度较大,而在F6~F10之间的变化幅度较小。聚类结果显示,F2群体的聚类结果没有规律性;F3~F10群体中,随着世代的不断增加,聚类结果的规律性越来越明显,同一株系间的单株越来越紧密地聚在一起。结果表明,F5~F7是作为剩余杂合系高效率筛选剩余杂合单株的理想世代;连续自交7代以上的群体(即F8)是可以用于遗传作图和QTL定位的芝麻RIL群体;F8群体的遗传背景比较趋于一致,为芝麻杂交育种中自交世代的确定提供了理论参考。
Recombinant inbred lines(RIL),which were generated by single seed descend method(SSD)with multiple generations from the F2 population,are commonly used in studies of the genetic mapping and the quantitative trait locus(QTL)mapping.Tracking and analyzing the genetic differences in generations of RILs might be of significance to assist the RIL population construction.In this study,18 SSR markers being polymorphic with parents were used to track the genetic diversity of F1 to F10 population during the RIL construction in sesame.With the increase of RIL population generations,the levels of polymorphism became decreased constantly from 87.54% of F2 to 3.33% of F10,the percentage of loci showing heterozygous decreased from 100% of F1 to 0.19% of F10,and the coefficient of genetic similarity increased from 0.6669 of F2 to 0.9908 of F10,and the genetic distance decreased from 0.2592 of F2 to 0.0094 of F10.The percentage of the polymorphism,the heterozygous loci,the genetic similarity coefficient as well as the genetic distance were variable in F2 to F6,while the level of variations became smaller in generations of F6 to F10.The clustering results showed that F2 plants were randomly classified,while in F3 to F10 generations the plants derived from the same line were clustered together.F5 to F7 populations are ideal to select residual heterozygous lines.The high-generation populations(>7 generations,i.e.F8)are qualified for the genetic mapping and QTL mapping.The genetic background of F8 population tends to be consistent,which provides theoretical reference for the determination of self-crossing generation in sesame hybridization breeding.
作者
孙建
叶艳英
梁俊超
乐美旺
颜廷献
饶月亮
颜小文
周红英
SUN Jian;YE Yan-ying;LIANG Jun-chao;LE Mei-wang;YAN Ting-xian;RAO Yue-liang;YAN Xiao-wen;ZHOU Hong-ying(Crops Research Institute of Jiangxi Academy of Agricultural Sciences/Jiangxi Province Key Laboratory of Oilcrops Biology/Nanchang Branch of National Center of Oilcrops Improvement,Nanchang 330200)
出处
《植物遗传资源学报》
CAS
CSCD
北大核心
2020年第4期914-922,929,共10页
Journal of Plant Genetic Resources
基金
国家自然科学基金项目(31560400)
国家现代农业产业技术体系建设项目(CARS-14)。
关键词
芝麻
重组自交系
构建过程
SSR
sesame(Sesamum indicum L.)
recombinant inbred lines(RIL)
population construction process
SSR
