玉米苗期根系性状配合力分析

选用8个玉米自交系,采用NCⅡ设计,组配15个杂交组合,研究玉米苗期根部性状配合力和遗传参数。结果表明,根长、根鲜质量、根体积、活根数、根干质量的变异系数分别为14.43%、23.58%、29.11%、32.32%、36.00%;根鲜质量、活根数和根体积等组合间差异均达显著或极显著水平,根长组合间差异不显著。根鲜质量和活根数父母本GCA方差达显著水平;根体积父本GCA方差达显著水平,母本GCA方差不显著;根鲜质量和活根数母本GCA基因型方差大于父本,而根体积父本GCA基因型方差较大,活根数SCA基因型方差远大于父母本GCA基因型方差,其狭义遗传力也最小,仅为5.88%,而根鲜质量和根体积的狭义遗传力较高,分别为26.19%和25.23%。根长基因型间无显著差异,根鲜质量和根体积在遗传上以加性效应为主,活根数则以非加性效应为主。

Analysis on the Combination Ability of the Root During Maize Seeding

In order to provide theoretical basis for breeding of drought-tolerant maize,the combination ability and genetic parameters of the roots of maize seedling were investigated.Eight maize inbred lines were divided into two groups,including five lines as female and three as male,respectively,to produce fifteen combinations by NCⅡ design.Five root traits,including number of living root,the fresh weight,the root volume,the root length and the dry weight,were measured and their combination ability and genetic parameters analyzed at the seeding stage.The coefficient of variation of root length,fresh weight,the root volume,number of living root,and the dry weight was14.43%,23.58%,29.11%,32.32%,and 36.00% respectively.The differences of fresh weight,number of living root,and the root volume,except for the root length,were significantly among different combinations but not among replications.Both the variance of general combination ability(GCA) of the female and male parents reached significant level on fresh weight and number of living root traits.The GCA variance of root volume of male parents reached significant level but not for the female parents,and the GCA variance of the females was larger than the males.The variance of specific combination ability(SCA) of number of living root was much larger than variance of GCA,and the narrow sense heritability was the least one,only 5.88%.In comparison,the narrow sense heritabilities of fresh weight,the root volume was 26.19% and 25.23%,respectively.In conclusion,there was no significant difference on the root length among different genotypes.The root fresh weight and root volume were mainly inherited by additive effect,but the number of living root was mainly determinated by non-additive effect.