A novel gene responsible for erect panicle from Oryza glumaepatula

ABSTRACT: The varieties with erect panicles used in rice breeding have led to a significant increase in rice yield. But the molecular mechanism of erect panicle remains elusive. Oryza glumaepatula, with the erect panicle phenotype, is an excellent gene pool to improve Asian cultivated rice O. sativa. In this study, a backcross introgression line was derived with Dianjingyou 1, a japonica cultivar, as the recurrent parent and an accession of O. glumaepatula as the donor parent. Using BC5F2 population, a novel gene responsible for erect panicle, EP4, was mapped within a 1.5 cM region flanked by SSR markers RM253 and RM19623 on the short arm of chromosome 6, at genetic distances of 0.4 and 1.1 cM, respectively. These results are useful for marker-assisted selection of erect panicles and for further cloning of the EP4 gene, which will contribute to the dissection of the molecular mechanism underlying erect panicles in rice.