云南部分玉米种质配合力和杂种优势的研究

 采用NC-II遗传交配设计,对7份美国自交系和7份本地自交系进行测交,通过9个性状研究其配合力和杂种优势,为利用外来种质拓宽玉米种质遗传基础开辟途径。结果表明:在被测系中,美国自交系HQPSSS株高、穗位高、行粒数、单株产量的一般配合力为极显著正效应,千粒重为正值,穗长、穗粗的一般配合力为较小的负值,本地自交系LA94-8多数性状的一般配合力为正值,特别是单株产量的GCA效应值最高,这是两个一般配合力较好的自交系。在测验种中,DAN340和LA8593B的多数性状表现出较好的一般配合力效应。HQPSCB×LA8593A,LA97-16×LQ16-2在各自的测交试验中单株产量的特殊配合力和杂种优势最高,分别比对照增产13.68%和23.8%. 在选育高产组合时,必须重视特殊配合力和杂种优势的选择。

The Study on Combining Ability and Heterosis of Some Corn Germplasm in Yunnan

To probe the ways to increase genetic variance of corn germplasm, seven inbred lines from US and other seven inbred lines from Yunnan were tested by NC-II mating design using 9 characteristics to study their combining ability and heterosis. The results showed that for HQPSSS general combining ability (GCA) of plant height, ear height, kernels per row and plant yield were significantly positive. GCA of a thousand kernels weight was positive. GCA of stem diameter, ear length and ear diameter were small negative values. For LA94-8 GCA of most characteristics were positive, especially GCA of plant yield was maximum. There were good GCA for those two inbred lines. DAN340 and LA8593B were good testers because they had higher GCA in most characteristics. HQPSCB×LA8593A and LA97-16×LQ16-2 had maximum values of special combining ability (SCA), and relative heterosis were 13.68% and 23.8% in their test respectively. For screening the cross of high yield, SCA and heterosis should be paid attention in the selection.