不同施氮量对黔西北山区玉米生长及产量的影响

Impact of Different Nitrogen Fertilizer Application Rates on Corn Growth and Yield in Mountain Area of Northwest Guizhou

为了给黔西北山区玉米生产合理施用氮肥提供科学依据,以黔兴201为材料,采用田间试验研究5个不同施氮水平对玉米生长及产量的影响。结果表明:1)当施氮量为450～675kg/hm2时,黔兴201的叶面积系数较适宜,最大叶面积持续期长,干物质积累与分配合理,易形成较高产量,即在一定范围内增施氮肥可增加叶面积系数、叶绿素相对含量、穗粒数、干物质积累量和产量,氮肥施用量超过一定范围产量下降。2)氮肥对产量的模拟方程为y=7 233.25+10.807 3x-0.008 48x2,在95%可靠区间内,黔兴201玉米品种的最佳氮肥施用量为563.76kg/hm2时,其理论产量为9 132.12～12 129.50kg/hm2,纯收益达最大;在施氮量为637.23kg/hm2时,可获9 177.69～12 175.47kg/hm2的理论产量。

To provide a scientific reference production in northwest Guizhou, a field test was for rational application of nitrogen fertilizer in maize conducted to study the effects of five application levels of nitrogen fertilizer on the growth and yield of Qianxing 201. Results： 1） higher yield would be obtained easily owing to optimum LAI, long duration of maximum leaf area and rational accumulation and distribution of dry matter when the application level of nitrogen fertilizer ranged from 450 kg/hm2 to 675 kg/hm2. In a certain scope, increasing application amount of nitrogen fertilizer could enhance LAI, SPAD, kernels per spike, accumulation amount of dry matter and yield, while the yield would decrease when exceeding the scope. 2） the stimulant curve equation about the relation between yield and nitrogen application ration was y=7 233.25＋10. 8073x-0. 00848z2. According to this equation in 95% confidence interval,the best nitrogen application rate was 563.76kg/hm2 and the theoretical yield reached 9 132.12～ 12 129.50 kg/hmz , and the net return reached the maximum. The theoretical yield of 9 177.69～12 175.47 kg/hm2 would be obtained when the application amount of nitrogen fertilizer was 637.23 kg/hm2.