Morphological Characteristics of the Rice (Oryza sativa L.) with Red Pigmentation

Abstract

Seven rice germplasms with red pigmentation within the pericarp were isolated from a large mutant collection. These red pericarp phenotypes resulted from the functions of the Rc, Rd and RdRc genes. Among them, two brown pericarp of the Rc type, four red pericarp of the RdRc type, and one white pericarp of the Rd type were identified. Morphological and agronomic characteristics of those rice germplasms were studied. The Rc type germplasms have the faint red or brown color pericarp and the Rd types produce the white pericarp, whereas the RdRc type germplasms have the dark red pericarp. Most of the important agronomic characteristics including plant stature, tillering ability, spi-kelet fertility, and total grain yield were lower in the colored rice than those of the wild-type control. All of the studied colored rice germplasms had a tendency of easy seed-shattering in comparison to the control. These characteristics of newly identified germplasms will be useful for identifying the genes responsible for pericarp color phenotype determination.