籼型杂交水稻农艺性状的配合力研究

如何有效利用杂种优势已成为水稻增产的关键。本研究按照NCII遗传交配设计,将三系野败型杂交水稻的恢复系和微核心种质构成的115份优异籼稻品种,分别与4个两系不育系及1个三系不育系测交,分析各农艺性状配合力、遗传力及相互关系。结果表明,除单株有效穗数、主穗实粒数外,其他农艺性状一般配合力差异均达到极显著水平;除单株有效穗数外,其他各农艺性状特殊配合力差异也均达到极显著水平。同一组合的不同性状、同一亲本的不同组合所表现出的特殊配合力效应都有所不同,表明亲本的一般配合力水平与特殊配合力间没有固定的联系。在育种实践中,选取一般配合力高的亲本,同时兼具较高特殊配合力是获取高产杂交稻组合的关键。

Combining Ability Analysis ofAgronomic Trait in Indica × IndicaHybrid Rice

How to effectively use heterosis is the key of improving yield for rice.In present study, under North Carolina design II, 115 elite indicarice varieties, including three-way wild-abortive hybrid restorer line and mini-core collection, were separately crossed with four two-way restorer lines and one three-way sterile line to generate 575 tested crosses, and combining ability, heritability and correlations of nine agronomic traits were analyzed. Except for tillers per plant and filled grains per panicle, the general combining ability (GCA) variances of most agronomic traitswere extremely significant, and except fortillers per plant, the specific combining ability (SCA)variances of other agronomic traits wereextremely significant. The SCA of different traits in the same combination or SCA of same trait in different combinations sharing one parent were different,indicating no consistent relationship between SCA and parental GCA. Therefore, selection of high GCA parental line combining with superior SCAcombinations is the key to obtain high yield hybrid rice.