新疆冬小麦籽粒品质性状遗传差异与关联分析

Genetic difference and genome association analysis of grain quality traits in Xinjiang winter wheat

小麦籽粒品质与面粉加工的食品品质密切相关,是小麦早期品质选择的重要依据。本研究以产自新疆的134个冬小麦地方品种和54个育成品种为材料,对连续2年种植收获于新疆乌鲁木齐市、新疆伊宁市共计4个试验点的小麦籽粒进行品质检测与全基因组关联分析。结果表明,7个小麦籽粒品质性状的广义遗传力在62.14%~85.35%之间,由大到小排序依次为:硬度(85.35%)>湿面筋含量(78.44%)>出粉率(73.13%)>容重(72.50%)>沉降值(66.70%)>籽粒蛋白质含量(65.24%)>淀粉含量(62.14%)。在4个不同环境下,7个小麦籽粒品质性状表现为蛋白质含量、湿面筋含量、沉降值的变异相对较大,籽粒硬度的变异居中,淀粉含量、出粉率、容重的变异较小,多数籽粒品质性状间呈极显著相关性。设定阈值P<0.01,经关联分析,7个性状共检测到6605个显著性SNP标记,可解释6.021%~31.467%的变异。4个环境下检测到2个以上性状共有的多性状位点12个,可以解释6.233%~17.708%的表型变异。分别是蛋白质含量/沉降值、蛋白质含量/容重共有位点各1个,分别位于6A、2B上;蛋白质含量/湿面筋含量共有位点5个,分别位于3A、1B、6B、7B和7D上;沉降值/容重/籽粒硬度3个性状共有位点1个,位于5B上;蛋白质含量/沉降值/湿面筋含量3个性状共有位点3个,位于7A、3B和2D上,蛋白质含量/沉降值/湿面筋含量/容重4个性状共有位点1个,染色体位置未知。筛选出11个多性状、多环境品质相关基因,其中TraesCS6B01G347500编码一种储运蛋白,TraesCS1B01G395400编码碳水化合物转运蛋白/糖转运蛋白,TraesCS2D01G246500基因编码具有耐冷、耐盐、节水相关的蛋白ESKIMO1,可作为候选基因进行等位变异分析和标记开发,为小麦标记辅助选择育种提供分子工具。

Seven grain quality traits were tested in the panel of 188 winter wheat accessions from Xinjiang.Twelve co-associated genetic loci were detected in four different environments via GWAS,explaining 6.021%–31.467%phenotypic variation.Two pleiotropism loci,located on chromosomes 6A and 2B,associated with protein content and settlement value,protein content and bulk density of wheat.Five pleiotropism loci,located on 3A,1B,6B,7B,and 7D,shared by protein content and wet gluten content.One pleiotropism locus,located on 5B chromosome,associated with settlement value,bulk density of wheat and grain hardness.Three pleiotropism loci located on 7A,3B,and 2D,respectively,which shared by protein content,settlement value,and wet gluten content,while one pleiotropism locus with unknown site was also associated with protein content,settlement value,and wet gluten content.These associated loci or genes might be employed to select favorite wheat genotypes,and cultivate elite wheat genotypes via marker-assisted selection in wheat quality breeding.Candidate genes at stable loci associated with multiple traits were searched,and 11 candidate genes that might be related to wheat grain quality with multiple traits and environments were screened.Among them,TraesCS6B01G347500 encoded a storage and transportation protein,TraesCS1B01G395400 en-coded a carbohydrate transport protein/sugar transport protein,and TraesCS2D01G246500 gene encoded a protein ESKIMO1 related to cold tolerance,salt tolerance,and water conservation.These genes can be used as candidate genes for allelic variation analysis and marker development,provide molecular tools for wheat marker assisted selection breeding.