普通小麦籽粒硬度的全基因组关联分析

籽粒硬度是小麦品质评价的重要指标。为挖掘控制小麦籽粒硬度的重要基因/位点,以国内外171个小麦品种组成的自然群体为材料,在4个环境下利用小麦90K SNP芯片对籽粒硬度进行全基因组关联分析(genome-wide association study, GWAS)。171个小麦品种籽粒硬度变异系数为56.59%～66.80%,相关系数为0.88～0.92。GWAS结果表明,共检测到20个与小麦籽粒硬度显著相关的SNPs,其中,14个SNPs(7个位点)在2个及以上环境中能被检测到,分别位于1A、1B、1D、2A、5A和7A染色体上,可解释6.76%～11.79%的表型变异。表型贡献率超过10%的SNPs有4个(3个位点),分布在1D、2A和5A染色体上,其中,1D染色体上的标记wsnp_Ku_c19622_29138795在3个环境中能被检测到,可解释9.08%～11.79%的表型变异;2A染色体上的标记Excalibur_c12675_1789在4个环境中均能被检测到,可解释9.10%～10.86%的表型变异;5A染色体上的标记wsnp_Ra_c24707_34262900和BS00041219_51在2个环境中能被检测到,可解释6.76%～10.35%的表型变异。在所有环境下均与小麦籽粒硬度显著相关的位点有4个,分别位于1A、1B、2A和7A染色体上。

Genome-Wide Association Study of Grain Hardness in Common Wheat

Grain hardness is an important index for wheat quality evaluation. Identification of associated genes/loci for grain hardness is important for molecular marker-assisted selection (MAS) in wheat quality breeding.In the present study,grain hardness was screened with 171 bread wheat varieties from China and abroad in four environments. A genome-wide association study (GWAS) was performed using the mixed linear model (MLM) based on wheat 90K SNP array.The variation coefficient of hardness was 56.59%-66.80%,and the correlation coefficient was 0.88-0.92. Eight stable loci with 14 SNPs were detected in two or more environments,located on chromosomes 1A,1B,1D,2A,5A and 7A,explaining the phenotypic variation of 6.76%-11.79%. Three loci with 4 SNPs could explain more than 10% of the phenotypic variation,located on chromosomes 1D,2A and 5A, and wsnp_Ku_c19622_29138795 marker detected on chromosome 1D in three environments could explain the phenotypic variation rate of 9.08%-11.79%,Excalibur_c12675_1789 marker detected on chromosome 2A in all four environments could explain the phenotypic variation rate of 9.10%-10.86%,the wsnp_Ra_c24707_34262900 and BS00041219_51 markers detected on chromosome 5A in two environments could explain the phenotypic variation rate of 6.76%- 10.35%. Four loci significantly associated with grain hardness in all environments were located on chromosomes 1A,1B,2A and 7A,respectively. The detected loci and corresponding SNPs could provide an effective way for improving the molecular markers for grain hardness selection in wheat breeding.