水稻의 耐冷性에 關與하는 몇가지 形質의 遺傳에 關한 硏究

Studies on the Inheritance of Several Characters Related to Cold Tolerance in Rice

In order to determine the inheritance of several characters related to cold tolerance in rice, F₁ hybrids were made by diallel cross among six rice varieties slowing the different reactions for cold tolerance. Parents, F₁ and F₂ plants were subjected to low temperature of 10℃ for 10 days in the phytotron at seedling stage. Another set of hybrid populations planted lately in field to distinguish the degree of leaf discoloration in late autumn. Most of crosses that crossed with M₁49 and IR800-14-3-2 showed relatively high specific combining abilities in cold tolerance. The results of Fl diallel analysis and the segregation mode of F2 plants for cold tolerance at seedling stage showed that cold tolerance was complete dominance aver cold susceptibility. In case of leaf discoloration in the field, the segregation mode also agreed with simple inheritance ratio(3 : 1). But it has not indentified that these segregation ratio can be agreed with those under different temperature conditions and those of much more cross combinations. In Vr-Wr graphical analysis, M₁49 and IR800-14-3-2 appeared to be contained most of dominant genes for cold to lerance, while IR1317-392-1-2-2 contained most of recessive genes. In the inheritance of days to heading of parents in the late season culture, early maturity showed partial dominance over late maturity. It was demonstrated that several combinations crossed with cold tolerant variety, IR800-14-3-2 or M₁49, had relatively high s.c.a. effects for early maturity.