两系法籼型品种间杂种优势的初步研究

Studies on Heterods of Intervarietal Hybrids of Indica by Two-line System in Rice

用９个籼型光（温）毓核不育系和１２个籼稻品种配制成８３个组合，对其生育期等８个主要性状进行考查分析，总结出籼型品种间两系杂交稻优势表现的一般规律，并对当前两系杂交稻研究和利用中的有关问题和组合选配的一般原则进行了讨论．

The beterosis of 83 crosses made with 9 indica photo （tbermo）-sensitive genic male sterile （PGMS） lines and 12 indica varieties （or lines） was surveyed and analyzed on 7 major characters in 1992, with the following results： （1） The growth duration of 80% crosses was between that of both parents, and influenced more by the earlier-matured one. About 15% crosses with shorter duration than the earlier parent mostly happened in the early x early or early x medium crosses. （2） The plant height of 100% crosses was between that of both parents, and inclinable to the taller one . （3） The seed set of 80% crosses was normal , ing that the PGWS lines were very easy to be restored. （4） The 1000-grain weight of almost 90% crosses was between that of both parents, and affected more by the female parent. （5） With more and larger panicles and heavier grains 50% crosses expressed＂ 10% higher yield than the male parent , 6% crosses yielded higher than the check combination Shanyou 63.