Genome-wide association analysis of kernel nutritional quality in two natural maize populations

Abstract

As one of three staple crops, nutritional traits in maize are important for human and animal nutrition. Grain quality-related traits are closely related to grain commercial value. Understanding the genetic basis of quality-related traits in maize would be helpful for breeding high-quality maize varieties. In this study, two association panels (AM122 and AM180) were subjected to genome-wide association analysis of grain qualityrelated traits, including protein content, oil content, starch content and bre content. In total, 98 SNPs (P<1×10-4) were identi ed to be signi cantly associated with these four grain quality-related traits. By integrating two sets of public transcriptome data, 31 genes located in 200 kb regions anking the associated SNP showed high expression during kernel development and were differentially expressed in two maize inbred lines, KA225 and KB035, with signi cantly different quality. These genes might regulate maize grain quality by participating in plant hormone processes, autophagy processes and others. All these results could provide important reference information for breeding high-quality maize varieties.