Development of an Aus-Derived Nested Association Mapping (Aus-NAM) Population in Rice

Abstract

A genetic resource for studying genetic architecture of agronomic traits and environmental adaptation is essential for crop improvements. Here, we report the development of a rice nested association mapping population (<i>aus</i>-NAM) using 7 <i>aus</i> varieties as diversity donors and T65 as the common parent. <i>Aus</i>-NAM showed broad phenotypic variations. To test whether <i>aus</i>-NAM was useful for quantitative trait loci (QTL) mapping, known flowering genes (<i>Ehd1</i>, <i>Hd1</i>, and <i>Ghd7</i>) in rice were characterized using single-family QTL mapping, joint QTL mapping, and the methods based on genome-wide association study (GWAS). <i>Ehd1</i> was detected in all the seven families and all the methods. On the other hand, <i>Hd1</i> and <i>Ghd7</i> were detected in some families, and joint QTL mapping and GWAS-based methods resulted in weaker and uncertain peaks. Overall, the high allelic variations in <i>aus</i>-NAM provide a valuable genetic resource for the rice community.