벼에서 웅성불임을 유발하는 심백미 돌연변이 계통 “화청ms-h” 배유의 이화학적 특성

Physicochemical characteristics of endosperm in a white-core mutant line “Hwacheong ms-h” causing male sterility in rice

This study was carried out to elucidate the physicochemical characteristics of endosperm of a white-core mutant line “Hwacheong ms-h” causing male sterility newly induced by chemical mutagen from a Korean japonica rice cultivar, Hwacheongbyeo. Amylose content of the white-core endosperm of Hwacheong ms-h was 4% lower in rice flour, but 3% higher in starch as compared with the normal endosperm of Hwacheongbyeo. Gel consistency of Hwacheong ms-h was much harder than that of Hwacheongbyeo. Lipid content was increased, and fatty acid composition was slightly modified with reduced linoleic acid and increased palmitic acid in Hwacheong ms-h. The Mg and K content was markedly increased, however, Mg/K ratio was decreased in the mutant grain. Starch granules in endosperm of Hwacheong ms-h were more roundish polyhedral and smaller than those of Hwacheongbyeo. Hwacheong ms-h was revealed to have quite different starch structure composed with higher frequencies of long glucose chain amylose, higher Fr. Ⅲ/Fr. Ⅱ ratio, and shorter branching of amylopectin as compared with Hwacheongbyeo. The peak, hot and breakdown viscosities of rice flour by Rapid visco-analyzer were significantly decreased but the consistency and setback viscosities were markedly increased in Hwacheong ms-h.