利用SNP标记和宁7840×Clark重组自交系(RIL)群体检测小麦染色体偏分离区域

为给小麦偏分离规律研究及小麦农艺性状的QTL定位研究提供相关信息,以普通小麦(Triticum aestivum L.)宁7840和Clark杂交得到的F12重组自交系(RIL)为试验材料,利用筛选出的2 404个单核苷酸多态性SNP标记和291个SSR标记对该群体进行遗传分析。结果表明,共有494个标记位点表现偏分离,占总标记数的18.3%,其中有429个标记偏向父本Clark,占偏分离标记数的86.8%,65个标记偏向母本宁7840,占偏分离标记数的13.2%。大多数偏分离标记在连锁图谱上成簇分布,形成偏分离区域(Segregation distortion region,SDR),共检测到33个SDR,分别位于1A、1B、2A、2B、3A、4B、5A、6A、6B、7A、7B和7D染色体上,其中有6个SDR偏向母本宁7840,27个SDR偏向父本Clark。杂合致死基因Ne2、导致偏分离的QSd.ksu-7D、核质互作增强子基因scs所在染色体区间分别与SDR-2B.1、SDR-7D.1、SDR-1A.2存在部分重合,这3个SDR中可能存在上述基因或其同源基因,在合子体选择和配子体选择共同作用下造成偏分离,形成SDR。

Detection of Wheat Chromosome Segregation Distortion Region Using SNP Markers and RIL Population of Ning 7840/Clark

The 127 Recombinant Inbred Lines (RILs) from the cross of common wheat (Triticum aestivum L.) Ning 7840 and Clark were used as the plant materials, genetic analysis was conducted with 2404 SNP markers and 291 SSR polymorphic markers. The results indicated that a total of 494 markers showed segregation distortion. Among them, 429 distorted markers, accounting for 86.8%, were biased to male parent Clark and 65 distorted markers, accounting for 13.2%, were skew to female parent Ning 7840. Most of the distorted markers were clustered to segregation distortion regions (SDRs), and 33 SDRs were detected on 1A, 1B, 2A, 2B, 3A, 4B, 5A, 6A, 6B, 7A, 7B, and 7D chromosomes. 6 SDRs were distorted to Clark, while 27 SDRs were skewed to Ning 7840. The chromosome intervals of hybrid necrosis gene Ne2 ,segregation distortion gene QSd.ksu-7D , nuclear-cytoplasmic compatibility enhancer gene scs were partially overlaped with SDR-2B.1, SDR-7D.1 and SDR-1A.2, respectively, which indicated that the three genes or homologous genes possibly located in three SDRs. The formation of segregation distortion regions was caused by gamete selection and zygote selection. These results will provide relevant information for the researches of wheat segregation distortion and QTL mapping of agronomic traits of wheat.