Genome-Wide Association Study Identifies Main Factors Controlling the Anthocyanidin Accumulation in Rice Leaves

Genome-wide association study (GWAS) has been widely used to detect associations between genes and crop traits. Anthocyanidin is a natural pigment for protection from damage by biotic and abiotic stresses and for reproduction. The synthesis of anthocyanidin in plants mainly involves 7 to 8 structural genes and several regulatory transcription factors. The anthocyanidin contents in leaves of 49 wild rice species were analyzed using high performance liquid chromatography (HPLC). The result showed that anthocyanidin accumulation was detected more or less in most wild rice species, indicating that the anthocyanidin accumulation is a common phenotype in wild rice. However, purple leaf is a rare phenotype in cultivated rice, demonstrating it is a trait with artificial selection during rice demonstration. The anthocyanidin in leaves of a worldwide germplasm collection consisting of 533 rice landraces were measured by HPLC, and then GWAS was conducted. The result would help illustrate the key factors under artificial selection for non-anthocyanidin phenotype during rice demonstration.