小麦耐低磷相关性状的全基因组关联分析

通过对小麦耐低磷相关性状进行全基因组关联分析(GWAS,genome-wide association study),挖掘与小麦耐低磷性显著相关的单核苷酸多态性标记(SNP,single nucleotide polymorphism)位点及候选基因,为小麦耐低磷性状的遗传基础和分子机制研究提供理论参考。本试验以198份黄淮麦区小麦品种(系)为试验材料,设置低磷和正常磷营养液水培试验,利用小麦35K芯片对分布于小麦全基因组的11896个SNP,采用Q+K关联模型对小麦耐低磷性相关性状进行关联分析。结果表明,小麦耐低磷性状表现出广泛的表型变异,变异系数为15.65%~26.59%,多态性信息含量(PIC,polymorphic information content)为0.095~0.500。群体结构分析表明,试验所用自然群体可分为2个亚群,GWAS共检测到67个与小麦耐低磷相关性状显著关联的SNP位点(P≤0.001),这些位点分布在除3A、3B和3D以外的18条染色体上,单个SNP位点可解释5.826%~9.552%的表型变异。在这些显著位点中有4个SNP位点同时关联到了2个不同的耐低磷性状。对67个SNP位点进行发掘,筛选到7个可能与小麦耐低磷性有关的候选基因。TraesCS6A02G001000和TraesCS6A02G001100在锌指合成中有重要作用;TraesCS6A02G118100可能为低磷胁迫诱导基因;TraesCS5D02G536400、TraesCS1B02G154200和TraesCS5D02G536500与低磷胁迫相关酶类基因家族有关;TraesCS1D02G231200与植物DUF 538结构域蛋白有关,是植物胁迫相关调控蛋白候选基因。

Genome-Wide Association Study of Low-Phosphorus Tolerance Related Traits in Wheat

To screen the single nucleotide polymorphism(SNP)loci and candidate genes associated with low-phosphorus stress in wheat,genome-wide association study(GWAS)of low-phosphorus related traits in common wheat was performed for understanding the genetic mechanism of low-phosphorus tolerance.In the study,198 wheat varieties(lines)originated from the Huang-Huai area were used as test materials to evaluate the related traits in low phosphorus and normal phosphorus solution cultures.The wheat 35 K Chip with 11896 SNP markers which were distributed in the whole genome of wheat were used to analyze the related traits of lowphosphorus tolerance.The mixed model of Q+K was chosen to determine the statistical associations between phenotypes and genotypes to evaluate the effects of population structure and related traits.The result showed that the low-phosphorus tolerance character of wheat had a wide range of phenotypic variation with the coefficient variation between 15.65%and 26.59%.The polymorphism information content(PIC)was between 0.095 and 0.500.Population structure analysis showed that the natural population in the experiment could be divided into two subgroups.GWAS analysis indicated that 67 SNP loci were significantly associated with low-phosphorus tolerance(p≤0.001),which were located in 18 chromosomes except 3 A,3 B and 3 D chromosomes.Each SNP could explain 5.826%~9.552%of phenotypic variation.Four SNP sites were simultaneously associated with 2 different low-phosphorus tolerance traits in these significant sites.Seven candidate genes may be related to the low-phosphorus tolerance of wheat through analysis of the 67 SNP sites.TraesCS6 A02 G001000 and TraesCS6 A02 G001100 play important roles in the synthesis of zinc finger.TraesCS6 A02 G118100 may be induced by low-phosphorus stress.TraesCS5 D02 G536400,TraesCS1 B02 G154200 and TraesCS5 D02 G536500 are related to the family of low-phosphorus stress-related enzymes.TraesCS1 D02 G231200 is related to DUF538 and its product can be a putative candidate for common stress-related protein in plant.