9个不同玉米人工合成群体育种潜势的比较

Breeding Potential Comparison of Nine Synthetic Maize Populations

借助不完全双列杂交遗传交配设计，采用群体性状表型鉴定结合配合力分析的方法，对9个供试群体的育种潜势进行综合评价，并对群体合成的方式做初步探讨。结果表明，供试群体内均存在较丰富的遗传变异，且经济性状变异程度普遍高于农艺性状，群体间主要性状及其配合力差异更为明显。群体06P7和06P8主要产量性状及其GCA表现较好，较对照高产组合出现次数多，且平均对照优势大，具有较大的改良利用潜力；对照群体GP-5虽主要产量性状均值较高，变异程度较大，且株高、穗位相对较矮，GCA负向效应较大，但主要产量性状GCA表现较差，需导人高配基因重组后，方可进一步改良利用；群体06P2和06P6主要产量性状及其GCA表现较差，育种潜力不大。小群体06P1—06P8与大群体GP－5的比较结果表明，在一定亲本数量的基础上，合成群体水平的高低与其参与合成亲本的优劣以及重组次数的多少关系更为密切。

Incomplete diallel cross design, together with the method of combinating the characterization of population phenotypes with the identification of combining ability,were employed to investigate the breeding potential of nine synthetic populations of maize and explore the method of population synthesis. Rich genetic variation was observed within populations, and the mutation degree of economic traits was higher than that of agronomic traits, and also obvious differences in the main population traits and the general combining ability （GCA） was observed. With better major yield traits and the GCA performance than the control,together with the average advantage of the control,06P7 and 06P8 seemed to have great potential for improvement; GP-5 of the control group, although with the higher mean of major yield traits and larger variation degree ,the output of the main traits and the performance of the GCA were poor. It needed high import genetic recombination before further utilization improving; 06P2 and 06P6, with the main yield traits poor performance of GCA,were not the potential for breeding. Comparison with the results of 06P1 - 06P8 small populations and large populations of GP-5 showed that a certain number of parents on the basis of the synthesis of high and low levels of populations involved in its synthesis of the pro-restructuring, as well as its pros and cons of how much more closely related.