粮棉轮作模式下氮磷钾施用量对玉米产量及产量构成的影响

为了明确河北省中南部干旱半干旱地区棉区棉花-小麦-玉米两年三熟粮棉轮作种植模式下玉米季的适宜施肥量,为生产上实现经济施肥提供理论依据,在大田条件下采用随机区组试验设计,将N、P_2O_5、K_2O施用量均分别设置0、75、150、225、300 kg/hm~2计5个水平,研究了各肥料不同施用水平对玉米产量构成及产量的影响。结果表明:随着施N量的增加,玉米穗长、穗粗、穗粒数、百粒重和产量均呈先增加后降低的变化趋势,其中,施N量为225 kg/hm~2时所有指标值均最高,在施N量≤225 kg/hm~2时产量随着施N量的增加而逐渐显著提高,而施N量225 kg/hm~2时产量增加不再明显;随着施P_2O_5量的增加,玉米百粒重和产量呈略有降低的趋势,但不同施肥量处理的调查指标差异均不显著;随着施K_2O量的增加,玉米穗粒数和产量呈逐渐增加趋势,但不同施肥量处理的产量差异均不显著。在当前粮棉轮作模式下,玉米季适宜的施肥量为N 225 kg/hm~2、K_2O 75 kg/hm~2,免施磷肥。

Effects of Nitrogen and Phosphorus and Potassium Rates on Maize Yield and Yield Components in Cotton-wheat-maize Rotation System

The aim of this experiment was to identify the optimum fertilizer rates for maize in cotton-wheat-maize rotation system in the arid and semi-arid areas of central and south of Hebei Province,and provide theoretical basis for economic fertilization in production. Adopting randomized block design in fields five treatments (0,75,150,225,300 kg/hm2) for each N,P2O5,K2O were designed to study the effect of fertilizer rates on maize yield and yield components. The results showed that with the increase of nitrogen grains per ear,hundred-grain weight and maize yield increased firstly then decreased,and when nitrogen rate reached 225 kg/hm2 the values were all the highest,and less than or equal to 225 kg/hm2, the yield increased with the increase of nitrogen rate,while the nitrogen rate greater than 225 kg/hm2, the yield increasing was not obvious. With the increase of P2O5 hundred-grains weight and maize yield de-creased, but there were no significant differences betweeen tre atments. With th e increase of K2O rate, grains per ear and yield increased gradually,and utilizing potassium increased yield significantly but there were no significant differences between treatments of utilizing potassium. For maize in cotton-wheat-maize rotation system the optimum fertilizer amount was N 225kg/hm2,K2O 75kg/hm2 and without P2O5.