벼에서 저아밀로스 배유 돌연변이체의 유전과 몇가지 이화학적 특성

Inheritance and some physicochemical properties of newly induced “low-amylose endosperm” mutants in rice

This study was carried out to investigate the inheritance of dull endosperm mutants newly induced from Hwacheongbyeo. Some physicochemical properties of low-amylose and waxy mutants derived from Hwacheongbyeo and Kinmaze were also examined. The low-amylose endosperm of a mutant line 48486 was found to be expressed by homozygotic pairing of two independent recessive genes, and the genes were designated tentatively as du-6a(t) and du-6b(t). The low-amylose endosperm of a mutant line 47320 was transmitted to the progeny only through female parents and segregated as dull : translucent = 1 : 1 in F₂ seeds and the pollen grains of heterozygous plants were semi-fertile, indicating that the gene conferring low-amylose endosperm of 47320 has an pleiotrophic effect on pollen sterility. It was designated tentatively as Du-7(t) Grains of the mutant lines were shorter as a whole, while grains of du-4 lines were slightly longer as compared with those of original cultivars, and the absolute grain density and grain hardness of them were lower than those of the original cultivars. Amylose content of low-amylose endosperm mutants derived from Hwacheongbyeo ranged from 4% to 10%. Alkali digestibility values of the mutants were similar to those of original cultivars. Gel consistency of the original cultivars was soft, while that of mutants varied from medium to soft. Particularly, Hwacheong du-4, Hwacheong du-6, EM21 (wx) and EM98 (du-4) showed extremely soft gel consistency. A. D. V. of mutants varied and water absorption of those was faster than original cultivars. Amylograph characteristics of Hwacheong low-amylose mutants were found to be intermediate as compared with those of original cultivar and waxy mutant. However, Kinmaze-derived mutants showed various amylogram pattern.