不同供氮水平下玉米生产力的杂种优势特征

Heterosis Characteristics of Maize Productivity under Different Nitrogen Supply Levels

以2个杂交种及其亲本为试验材料,研究玉米杂交种及其亲本生产力对供氮水平的响应及不同供氮水平下生产力的杂种优势特征。结果表明,吉单27的单株子粒产量对供氮水平的响应趋势与其父本四144相同,施氮量在0~150 kg/hm^(2)范围内,随施氮水平增加子粒产量呈递增趋势;施氮量超过150 kg/hm^(2)后,单株子粒产量对增施氮肥无响应。四单19的单株子粒产量对供氮水平的响应趋势与其母本444相同,施氮与不施氮处理间差异显著,75、150、225和300 kg/hm^(2)4个供氮水平下差异不显著,其父本Mo17对施氮与不施氮及不同供氮水平的变化均没有响应。吉单27和四单19两个品种的单株干物质积累与子粒产量的中亲优势、超亲优势和相对优势对供氮水平的响应趋势明显不同,吉单27的杂种优势随施氮量增加呈下降趋势,四单19的杂种优势随施氮量增加呈增长趋势。

In this study,2 hybrids and their parents were used as experimental materials to study the response of maize hybrid and their parent to nitrogen supply levels,as well as heterosis characteristics of productivity at different nitrogen supply levels.The results showed that the response trend of grain yield per plant of Jidan 27 to nitrogen supply level was the same as that of its parent Si144.The grain yield per plant of Jidan 27 increased with the increase of nitrogen application level from 0 to 150 kg/ha,but had no response to the increase of nitrogen application rate when the nitrogen application rate was more than 150 kg/ha.The response trend of grain yield per plant of Sidan 19 to nitrogen level was the same as that of parent plant 444,and there was significant difference between nitrogen application and no nitrogen application,while there was no response to increasing nitrogen application at 75,150,225 and 300 kg/ha levels,and its parent Mo17 showed no response to the changes of nitrogen supply level.The mid-parent heterosis,heterobeltiosis and relative advantages of dry matter accumulation per plant and grain yield of Jidan 27 and Sidan 19 were significantly different in response to nitrogen supply level.The heterosis of Jidan 27 decreased with the increase of nitrogen application,while that of Sidan 19 increased with the increase of nitrogen application.