以10个玉米F1代杂交种和18个玉米自交系为材料,研究玉米出籽率、千粒重和单穗粒重的改良效果和杂种优势等.结果表明,导入PH6WC的改良系在千粒重和单穗粒重方面明显优于未改良系,千粒重、单穗粒重的增幅分别为2.6%～12.3%和4.4%～9.5%;导入PH4CV的改良系在出籽率和单穗粒重方面明显优于未改良系,出籽率、单穗粒重的增幅分别为-0.3%～12.0%和16.8%～34.8%.新组合PH6WC×辽3250、辽3358×PH4CV和PH6WC×辽3258的产量分别为12 731.5、12 485.5、12 396.3 kg/hm2,与对照郑单958相比增产幅度达显著水平,具有较高的利用潜力.F1杂交种的出籽率呈近中亲遗传,千粒重和单穗粒重呈超显性遗传,均表现出正向杂种优势.
Used 10 F1 hybrids and 18 parental inbred lines as the experimental materials, the improved effects and heterosis of grain rate, 1 000-grain weight and yield per ear in maize were studied. The results showed that 1 000-grain weight and grain weight per ear of the improved lines by introducing PH6WC were significantly better that of unimproved lines, and the increasing range was from 2.6% to 12.3%, from 4.4% to 9.5% respectively. The rate of grain and grain weight per ear of the improved lines by introducing PH4CV were significantly better that of unimproved lines, and the increasing range was very high from -0.3% to 12.0%, from 16.8% to 34.8% respectively. The yield of new combination PH6WC×Liao3250, Liao3358×PH4CV and PH6WC×Liao3258 was 12 731.5 kg/ha, 12 485.5 kg/ha and 12 396.3 kg/ha, which was higher significantly than Zhengdan958 respectively. Rate of grain weight of all F1 hybrids represented mid-parent heredity, 1 000-grain weight and grain weight per ear of all F1 hybrids represented over dominance heredity．