Breeding Hybrid Rice with Good Quality and High Yield : Ⅱ. Combining Ability of the Cytoplasmic-Genetic Male Sterile and Restorer Lines with Backgrounds of Japonica Rice, and Heterosis for Yield and Grain Quality of the Hybrid Rices
우리나라 japonica형 품종을 배경으로 육성된 12개 웅성불임계통과 12개 임성회복계통들의 수량에 대한 조합능력을 조ㆍ중ㆍ만생군별로 검토하고 이들간 일대잡종들의 잡종강세정도와 미질특성을 검정한 결과를 요약하면 다음과 같다. 1. 공시된 웅성불임계통 중 오대벼 A, 화성벼A, 이리 386벼, 낙동벼 A, 팔굉 A와 임성회복계통중 오대벼 R, 호성벼 R, 이리 386 R, 팔굉 R, 화청벼 R 등의 수량에 대한 조합능력이 우수하였다. 2. 웅성불임계통과 임성회복계통간의 일대잡종에서 수량에 대한 heterobeltiosis는 조생군에서 -17%~15%, 중생군에서 -4~22%, 만생군에서 -46%~30%였다. 3. 일대잡종에서 수량에 대한 standard heterosis는 조생군에서 표준품종 화진벼에 대해 0~26%, 만생군에서 표준품종 화정벼에 대해 -38~26%였다. 4. 잡종강세정도가 정인 조합군에서는 수당영화수, 수수 등이 수량과 상관이 높았고, 부인 조합군에서는 임실율, 천입중 등이 수량과 상관이 높았다. 5. 공시된 일대잡종벼의 amylose 함량은 대부분조합에서 20% 미만이었고, 알칼리붕괴도, 심복백, 투명도, 장폭비 미질 관련 형질도 양호하였다.
In order to test combining ability of the cytoplasmic-genetic male sterile(CGMS) and restorer lines with backgrounds of Korean japonica rice varieties, diallel crosses were made among the early maturing CGMS lines Sobaegbyeo A, Odaebyeo A, Gwanagbyeo A and Daeseongbyeo A, and the restorer lines Sobaegbyeo R, Odaebyeo R, Gwanagbyeo Rand Daeseongbyeo R, and among the medium maturing CGMS lines Hwajinbyeo A, Paldal A, Suwon 224 A and Iri 386 A and the restorer lines Hwajinbyeo R, Paldal R, Suwon 224 Rand Iri 386 R, and among the late maturing CGMS lines Nagdongbyeo A, Palkweng A, Hwacheongbyeo A and Milyang 97 A and the restorer lines Nagdongbyeo R, Palkweng R, H wacheongbyeo Rand Milyang 97 R. The fourty eight combinations of the hybrids, their parents and the maintainers were grown in field condition in 1992. General combining ability, relative specific combining ability and relative combining ability for yield of the CGMS and restorer lines were tested. Combining ability of the CGMS lines Odaebyeo A, Iri 386 A, Nagdongbyeo A and Palkweng A, and of the restorer lines Odaebyeo R, Hwajinbyeo R, Hwacheongbyeo Rand Palkweng R was relatively high. Heterobeltiosis for grain yield over the better parent of the early maturing hybrids ranged from -17 % to 15%, and that of the medium maturing ones from -4% to 22%, and that of the late maturing ones from -46% to 30% respectively, Standard heterosis over the standard variety of the early maturing hybrids ranged from -13 % to 12 %, and that of the medium maturing ones from 0 % to 26%, and that of the late maturing ones from -38% to 26% respectively, Positive and negative heterosis for grain yield of the hybrid rices were observed depending on cross combinations, In the positive heterosis hybrids, number of panicles per hill and number of spikelets per panicle contributed mostly to grain yield, while in the negative heterosis hybrids, spikelet fertility and 1000 grain weight were closely correlated to grain yield. Amylose content of the hybrid rices, maintainer and restorer lines was mostly lower than 20 %, and alkali digestion value was higher than 6.0. Grain appearance of the hybrids tested was similar to the korean japonica rice varieties.