长江中下游麦区小麦地方种质千粒重全基因组关联分析

Genome-Wide Association Study of Thousand Kernel Weight in Chinese Wheat Landraces in the Middle and Lower Reaches of the Yangtze River

【目的】高产是小麦育种的永恒主题,千粒重是产量构成的三因子之一。因此,发掘控制小麦千粒重QTL(quantitative trait loci)区段及其优异等位变异,对利用分子标记辅助选择进行小麦产量性状的遗传改良具有重要意义。【方法】以来自长江中下游麦区188份小麦地方种质为材料,在3个环境下对小麦千粒重进行表型鉴定;利用DArT芯片(diversity arrays technology)进行全基因组扫描,基于一般线性模型(Q+K)对小麦千粒重进行关联分析。【结果】千粒重表型鉴定发现来自江苏、浙江和湖北小麦地方种质具有较高千粒重;通过全基因关联分析,共获得8个DArT标记在2个及以上的环境中均与小麦千粒重显著关联,分布于小麦染色体1B、1D、3B、4B和5B上,其表型贡献率9.19%~12.65%。【结论】长江中下游麦区小麦地方种质千粒重表型变异丰富;在不同环境中均能关联到的标记为较为稳定的控制小麦千粒重位点。

【Objective】High yield is the eternal theme of wheat breeding program and thousand kernel weight is one of the three factors of yield components.For exploring wheat grain weight QTLs and its allelic variations are great significance on genetic improvement of wheat yield traits using Marker-assisted selection.【Method】By investigated thousand kernel weight traits using 188 Chinese wheat landraces from the middle and lower reaches of the Yangtze River across three environments.Genome-wide association analysis was performed using wheat DArT-seq(diversity arrays technology)with general linear Q+K association models.【Result】The accessions,derived from Jiangsu,Zhejiang and Hubei Province,had good performance for thousand kernel weight traits.A total of 8 significant marker-trait associations(MTAs)were detected on chromosomes 1 B,1 D,3 B,4 B,and 5 B in more two environments.Single locus could explain 9.19%to 12.65%the observed phenotypic variation.【Conclusion】The thousand kernel weight traits performance are significant difference in Chinese wheat landraces from the middle and lower reaches of the Yangtze River;The stable loci associated with the thousand kernel weight are found in different environments.