两种方法对几个玉米自交系遗传特性及育种潜势的比较分析

Compare Analysis to Genetic Characteristics and Potential in Breeding of Maize (Zea mays L.) Inbred Lines Between

试验采用7个自选系、7个外引系、外杂选系和按NCⅡ组配的49个杂种F1组合为研究材料。应用混合线性模型、配合力两种分析方法对单株粒重的遗传方差和遗传力的分析结果进行了比较,并在此基础上对LUP两种效应值与两种配合力效应值进行了比较分析。结果表明混合模型分析只揭示了显性和加加上位性效应;而配合力分析是在加-显遗传模型基础上进行的,只能揭示加性和显性效应。两种分析方法所得各遗传方差分量与遗传力都基本一致。分析LUP所预测的单株粒重的各遗传效应值表明LUP加性效应各亲本系列(包括亲本效应)与一般配合力大小顺序完全一致;LUP的显性效应与各组合的特殊配合力及超对照优势均呈极显著的正相关关系(r=0.70和r=0.93),特殊配合力与超对照杂种优势的相关系数(r=0.56)也达到极显著水平。

Fourteen maize inbred lines and forty-nine crosses mated by NCⅡdesign were used in the experiment. The genetic effects of kernel weight/plant were analyzed with mixed linear model analysis and combining ability analysis. And the results were compared. The major results are as following: There are dominant and A-A epistatic genetic effect in the mixed linear model analysis. But combining ability analysis is based on additive-dominant model. It reveals that just have additive effect and dominant effect. The differences of genetic variance component and heritability between mixed model analysis and combining ability analysis are not significant. Array sum of parents(including parents effect) comply with GCA in number order(from high to low) .Correlation coefficient between the dominant effect of LUP(linear unbiased predict ) and SCA(special combining ability)/heterosis are 0.70 and 0.93 respectively at 0.01 significant level. Correlation coefficient between SCA and heterosis is just 0.56 at significant 0.01 level.