玉米籽粒颜色全基因组关联分析

Genome-wide Association Study of Kernel Colors in Maize

籽粒颜色是玉米重要的性状之一,籽粒色素影响玉米的营养价值和商品品质,解析其遗传机制对玉米优良种质选育至关重要。本研究以244份玉米优良自交系为材料,分析其籽粒颜色的遗传变异规律,并利用覆盖玉米全基因组的913万个SNP标记,开展籽粒颜色的全基因组关联分析,以期初步解析玉米籽粒颜色的遗传学基础。结果显示,共检测到258个SNP位点与玉米籽粒颜色性状紧密关联,其中与Level、R、G、B、Gray和RGB性状显著关联的SNP位点(Sig SNP)分别有27、11、7、197、5和11个,且有6个位点/区间(meta SNP)被至少2个性状同时定位到。所有显著性SNP位点附近共定位到482个候选基因,其中37个候选基因位于meta SNP区域,控制玉米黄白粒的Y1基因和类胡萝卜素合成的DXS3基因被籽粒颜色B值定位到。本研究结果可为进一步筛选控制籽粒颜色的基因和指导籽粒颜色选择育种提供理论基础。

Kernel color is one of the important traits of maize.kernel pigment affects the nutritional value and commodity quality of maize,and the analysis of its genetic mechanism is essential for the breeding of excellent maize germplasm.In this study,244 elite inbred lines of maize were used as materials to analyze the genetic variation of kernel color,and the genome-wide association analysis of kernel color was carried out using 9.13 million SNP markers covering the whole genome of maize in order to preliminarily analyze the genetic basis of kernel color of maize.The results showed that a total of 258 SNP loci were closely related to maize kernel color traits.Among them,there were 27,11,7,197,5 and 11 SNP loci(Sig SNP)significantly associated with level,R,G,B,Gray and RGB traits,respectively,and six loci/intervals(meta SNP)were simultaneously mapped by at least two traits.A total of 482 candidate genes were identified near all significant SNP loci,including 37 candidate genes co-located by different grain color traits in the meta SNP region,the Y1 gene and DXS3 gene controlling carotenoid biosynthesis in yellow and white grains of maize were mapped by kernel color B value.The results of this study can provide a theoretical basis for further screening genes controlling kernel color and guiding kernel color selection breeding.