6个玉米人工合成群体的育种潜势分析

Breeding Potential Analysis of Six Synthetic Maize Populations

【目的】系统评价6个玉米人工合成群体的育种潜势,为进一步改良利用提供合理方案。【方法】采用群体性状表型鉴定、配合力测定以及SSR标记对群体进行综合分析。【结果】多数性状与季节互作不明显,群体间多数性状差异极显著。多数农艺、经济性状的GCA群体间存在显著或极显著差异,少数经济性状的SCA组合间存在显著或极显著差异。26对SSR引物在供试群体内共扩增出246个等位位点。多态性位点数、多态位点比例、基因杂合度以及遗传距离等分析表明,除群体P1外,各群体遗传重组比较充分,群体内具有较丰富的遗传变异,且群体间遗传距离大于群体内遗传距离。【结论】群体P4、P2和P7除自身遗传变异较为丰富外,主要经济性状GCA较高,优于对照高产组合出现次数较多,育种潜力较大。群体P1、P3和P5经济性状GCA低,优于对照高产组合出现次数相对较少,需进行必要的改良。

[ Objective] To provide reasonable improvement programs for further improvement, we evaluated systematically breeding potential of six synthetic maize populations. [Method] Phenotype analysis, combining ability test and SSR molecular marker were employed in this research. [Result] Field results of the six synthetic populations observed in two seasons showed that variances were significant in most observed traits. Analysis of the general combining ability （GCA） showed that most agronomic and economic traits were significantly variant among the six populations. The special combining ability （SCA） of a few economic traits were significantly variant. A total of 246 alleles were detected using 26 pairs of SSR primers in the six populations. Analysis of polymorphic loci, the proportion of polymorphic loci, genes heterozygosity and genetic distance showed that each group is having full genetic recombination except group P1. Also genetic distances among six populations were larger than in-group genetic distance. [Conclusion] It is concluded that populations of P4,P2 and P7 were more genetically diversed than other groups, and their GCA of main economic traits higher than P1, P3 and P5. So they have better utilization value in maize breeding programs. GCA of economic traits in group P1, P3, P5 were low. More necessary improvements need to be made.