AGRONOMIC AND PHYSIOLOCAL CHARACTERIZATION OF VARIOUS COLOR PERICARP OF RICE (Oryza sativa L.)

Abstract

Colored rice is characterized by pigmented pericarps with high level of photochemical properties. In this study four colored rice varieties were used as planting materials to investigate the color developmental stages in the seed pericarp and its possible effect on different physiological and agronomic traits of colored rice in contrast with white rice. The phytochemicals are chlorophyll, anthocyanin and proanthocyanidin, which present only in the pericarp of green, red and black rice; respectively. At the seed developmental stage, green pericarp rice maintained green color in pericarp even after physiological maturity stage because the chlorophyll was faded away slowly. But red and black rice showed increasing color pigments deposition with simultaneous reduction of chlorophyll in the seed pericarp that indicates reducing photosynthetic rate, leading to low agronomic traits of colored rice. Most of the important agronomic traits value including plant height, tillering ability, spikelet fertility were lower in colored rice compared to white rice. Colored rice had lower value including 1000 seed weights, seed length and seed width that are related to total yield of colored rice in comparison to white rice. These findings clearly indicate that the lower agronomic traits of color pericarp rice in compare with white pericarp rice that might be due to the deposition of pigments in the pericarp. These findings suggest that the low yield of colored rice is closely related to physiological traits other than the agronomic traits.