Selection Response for Culm Length and Heading Days in the two Japonica × Dwarf Indica Combinations of Rice (Oryza sativa)

내병성 및 단간내도복성 인자의 이용을 목적으로 하는 수도 Japonica×lndica 조합에 있어서 선발효율에 관한 지견을 얻고저 關玉×IE 51및 振興×T(N)1 2조합의 F₂에서 각각 5%와 10%씩 간장과 출수일수에 관하여 선발하고 이들의 F₃을 재배조사하여 얻은 결과는 다음과 같다. (1) 關玉×IE 51 조합에서는 간장과 출수일수에 관한 선발효율이 높았다. (2) 振興×T(N)1조합에서는 간장에 관해서 heterosis가 크게 나타났으며 선발의 효율은 컸지만 이 heterosis를 감소시킨 정도였으며 출수 일수에 관한 선발의 효율은 높았다. (3) 선발강도 10%와 5%를 선발진전(selection advance)으로 비교하면 대체로 차가 없었으나 振興×T(N)1 조합의 출수일수에 관한 선발에서 5%선발은 10% 선발보다 selection advance가 컸다.

To investigate the selection efficiency for culm length and heading days in the Korean Japonica×dwarf Indica, in the F₂population of Kwanok×IE 51 and Jinhung×T(N)1 crosses, 5% and 10% selections were made for culm length and heading days, and they will be grown together with their parents next year. The results observed are as follows; (1) Selections for culm length were effective in the combination of Kwanok×IE 51 where F₂mode was between tall and short parents, but in the combination of Jinhung×T(N)1 where the F₂mode showed distinct heterosis, selection efficiency was meager. (2) Selections for heading days were effective in both combinations. (3) The selection advance made by 10% selection was as large as the one made by 5% selection in both combinations except the selection for heading days in Jinhung×T(N)1 combination, where 5% selection made more advance than 10% selection. (4) Heritability calculated by H= Gs/i was generally higher than that of H = Gs/KOA