水稻亚种间杂种基因效应和性状间相关性分析

Analysis of Genetic Effects and Correlations for Some Agronomic Traits in F_1 Inter-Subspecific Hybrids of Rice

以6份籼型型不育系和6份粳型或偏粳型广亲和系配制成不完全双列杂交，将杂种F1及其亲本在三个播期（5／20，6／10，6／30）试验，应用加性、显性与环境互作摸型，分析籼粳交杂种八个主要农艺性状的遗传方差组成、杂种优势的表现以及性状间的相关性等．结果表明：1）参试性状不仅加性方差和显性方差极显著，并且加性×环境或显性×环境互作方差也显著存在；但控制不同性状的基因效应稳定性尚有明显的差异．2）基因型×环境互作效应的结果，使杂种在多数性状上其群体平均优势和群体超亲优势均随播种推迟而呈下降的趋势；F1性状的平均基因型预测值显示了早播常出现植株偏高、剑叶较披和生育期相对延长，而迟播导致主穗总粒数减少3）性状间的加性和显性相关是决定遗传相关的主要因素；在株高、抽穗天数、剑叶长、主穗长和主穗总粒数等五个性状间，杂种的表型相关和遗传相关与遗传相关的四种分量间方向相同，均为显著正相关，所以要选育大穗高产的杂交组合及其配组材料，都应保证适宜的株高、生育期和剑叶长.

6 indica cytopiasmic male sterile lines and 6 japonica widely compatible varieties were used to make a set of incomplete diallel crosses．The field experiment was carried out at 3 different sowing dates（early 5／20，middle 6／10 and late 6／30）in 1993．The genetic effects for 8 agronimic traits were analyzed using additive-dominant×enviroment interaction model.The resuits indicated as below:（1）analysis genetic variance components showed significant on additive ×enviroment and dominant×enviroment as well as additive and dominant effects for the tested traits．However，the stability of genetic effects among the observed traits was different.（2）The F_1 hybrids showed different degree of heterosis resulted from genotype×environment effects under the three sowing onditions． The heterosis over both midparent and better-parent based on population means was decreased with the put off planting time for most characters．The predicted genotype values of hybrid was increased at the early sowing condition for plant height，flag leaf length and heading time，but was decreased at the later sowing condition for total number of grain per main panicle.(3)Additive correlation and dominant correlation were the major factors of genetic correlation among traits．The four components of genetic correlation were found to be positive correlations with phenotype or genotype correlation among 5 traits such as plant hight，days to heading，flag leaf length，main panicle length and total grain number per main panicle．