17个玉米地方种质选系的配合力分析

Analysis on Combining Ability of 17 Inbred Lines from Maize Landraces

分析玉米地方种质选系的配合力,可以为探明自交系的应用价值提供技术支撑。选用11个自交系为测验种,采用不完全双列杂交设计,对17个玉米地方种质新选的自交系的配合力、杂种优势以及主要性状遗传参数进行了分析。结果表明:单株产量GCA表现突出,且构成产量因子性状GCA表现也较好的新选自交系有P1-1、P1-16和P1-14;SCA值高、杂种优势强的组合是P2-4×P1-10;在株高、穗位高、穗行数等4个性状中,亲本的基因加性效应对F1性状形成起主导作用,而穗长、秃尖长、百粒质量等5个性状的遗传变异主要来自于基因非加性效应。因此,对于高产组合的选配,至少要选择1个GCA高的材料作亲本,并在此基础上兼顾SCA的选择,而利用地方种质选系则应根据性状遗传特性决定其选择时期和选择强度。

This study was carried out to analyze the combining ability of inbred lines from maize landraces in or-der to provide the theoretical basis for assessing potential value of inbred lines. The materials included 11 testers, which used commonly in Southwest regions,17 newly inbreds obtained from maize landraces,and 187（17 × 11）com-binations which were crossed with 17 new maize inbred lines and the 11 testers by NCⅡmating design. The combining ability of 17 inbred lines from landraces was analyzed based on the date for the experiment. The genetic parameters were done basing on combining ability. The results showed that P1-1,P1-16 and P1-14 with the better comprehensive characters can be directly used in maize breeding program. The SCA of P2-4 × P1-10 was high in most traits,they brought out strong heterosis. GCA variance was bigger than SCA variance in plant height,ear height,rows per ear etc four characters,yet SCA variance of ear length,sterile length and 100-kernel weight etc five characters was big-ger than GCA variance. So these characters were selected would be based on their heritability. For example,plant height,ear height,rows per ear etc can be selected in early stage,ear length,sterile length and 100-kernel weight etc ought to be selected in lately stage. We should pay attention to GCA,SCA when cross elite hybrid combinations.