Identification of as a positive awn regulator from two wild rice species.

The awn is a bristle-like appendage that protrudes from the seed tip and plays a critical role in preventing feed damage and spreading habitats in many grass species, including rice. While all wild species in the genus have awns, this trait has been eliminated in domesticated species due to its obstructive nature to agricultural processes. To date, several genes involved in awn development have been identified in wild rice, and which are ancestral species of cultivated rice in Asia and Africa, respectively. However, the responsible genes for awn development have not been identified in other wild rice species even though multiple QTLs have been reported previously. In this study, we identified gene responsible for awn development in two wild rice species, and . encodes a cytochrome P450 enzyme and is homologous to , a known brassinosteroid biosynthesis enzyme in rice. The identification of provides insight into a distinct molecular mechanism underlying awn development that occurs in geographically separated environments.