摘要
在干旱条件下,小麦(Triticum aestivum L.)适当深播可提高出苗率,胚芽鞘长度决定了小麦播种的最大深度,因此培育长胚芽鞘小麦品种至关重要.为了挖掘控制小麦胚芽鞘长度相关的数量性状位点(quantitative trait loci,QTL),本研究以 275份豆麦/石 4185重组自交系(recombinant inbred lines,RIL)群体和 186份自然群体为材料,根据 90K SNP芯片的分型结果,利用 3 个环境下小麦胚芽鞘长度表型数据进行QTL鉴定.采用完备区间作图法(inclusive composite interval mapping,ICIM)在 RIL 群体中鉴定到 2 个稳定的 QTL 位点,分别位于 4BS(30.17～40.59 Mb)和 6BL(700.08～703.53 Mb)染色体上,解释表型变异率(PVE)分别为 26.29%～28.46%和 4.16%～4.36%;全基因组关联分析(GWAS)采用混合线性模型(Mixed linear model,MLM)方法,共鉴定到 36 个稳定的QTL位点,分别位于 1A(3)、1B(3)、1D(2)、2A(1)、3A(2)、3B(2)、4B(11)、5A(1)、5B(3)、6B(4)、7A(2)、7B(2)染色体上,在 3 个环境中重复检测到的显著关联位点有7个,其中3个位点与已报道的位点重叠或邻近,其他4个位点推测为新位点,分别位于1A(499.03 Mb)、3A(73.06 Mb)、4B(648.74～648.87 Mb)、7A(36.31 Mb)染色体上,预测了 5 个候选基因(TraesCS1A03G0748300、Rht1、TraesCS4B03G0110000、TraesCS4B03G0112200 和 TraesCS7A03G0146600).在两个群体中均鉴定到位于 4BS(30.17～40.59 Mb)染色体上的主效QTL位点,该位点的候选基因Rht1 已被证实能降低小麦胚芽鞘长度.该研究结果为挖掘控制小麦胚芽鞘长度的基因以及胚芽鞘长度相关性状分子标记辅助选择育种奠定了基础.
Abstract
Under drought conditions,the emergence rate of wheat(Triticum aestivum L.)can be improved by proper deep sowing.The maximum sowing depth of wheat is determined by the length of the coleoptile,so it is very important to cultivate wheat va-rieties with long coleoptile.In this study,a recombinant inbred line(RIL)population consisting of 275 lines derived from the cross of Doumai and Shi 4185,and 186 natural population materials were used as the experimental materials.Genotyping results of 90K SNP chip were used to identify QTL for wheat coleoptile length in three different environments.The results showed that two stable QTL sites were identified by inclusive composite interval mapping in the RIL population.The two QTL located on Chromosome 4BS(30.17-40.59 Mb)and 6BL(700.08-703.53 Mb),respectively,and explained 26.29%-28.46%and 4.16%-4.36%of the phenotypic variance,respectively.A total of 36 stable QTL were identified in the genome-wide association study(GWAS)using the mixed linear model.They were located on Chromosome 1A(3),1B(3),1D(2),2A(1),3A(2),3B(2),4B(11),5A(1),5B(3),6B(4),7A(2),and 7B(2),respectively.Seven significant association loci were repeatedly detected in the three environments,three of which overlapped or were adjacent to reported loci,and the other four loci were presumed to be new loci.They were located on Chromosomes 1A(499.03 Mb),3A(73.06 Mb),4B(648.74-648.87 Mb),and 7A(36.31 Mb),respectively.Five candidate genes(TraesCS1A03G0748300,Rht1,TraesCS4B03G0110000,TraesCS4B03G0112200,and TraesCS7A03G0146600)were predicted.A major QTL locus on Chromosome 4BS(30.17-40.59 Mb)was identified in both RIL and natural populations,and the candidate gene Rht1 at this locus had been shown to reduce the length of wheat coleoptile.The results of this study lay a foundation for the identification of genes controlling the length of coleoptile in wheat and the maker-assisted selection breeding.
基金项目
青岛农业大学高层次人才科研启动基金(663/1122023)
山东省自然科学基金项目(ZR202103020229)
国家自然科学基金青年科学基金项目(32101733)
维普
万方数据