降雨量和氮素对黑土区春玉米产量的影响

为了研究在田间旱作农业条件下主要生长因子对玉米产量的影响,采用同一品种春玉米、同一“3414”肥料试验设计方案,在土壤有效氮量中等,有效磷、钾含量均较高的黑土上进行了连续3年的玉米田间试验.结果表明,影响玉米产量的3个主要因素分别是玉米生育期降雨量、氮肥施用量和土壤氮素水平.玉米生育期降雨量对产量的影响最大,生育期降雨量越大,玉米产量越高,二者之间呈正相关关系.只有在生育期降雨大于280 mm的情况下,施用氮肥才有较为明显的增产效果,低于此值,氮肥增产效果不明显.与不施肥相比,施用氮、磷、钾肥平均增加水分利用效率24.3％.玉米产量与播前土壤碱解氮之间旱正比,高水平的土壤碱解氮有利于玉米产量的提高.

Effects of precipitation and nitrogen on spring corn yield in black soil regions

The objective of this study was to distinguish effects of main growing factors on the corn yield under dry-farming conditions. A corn field experiment with three factors and four levels for each factor was conducted using the same corn cultivar and the same design in three consecutive years on a black soil classified as typic udolls of which the available nitrogen is middle but both available phosphorus and potassium are high. The results showed that, the most limiting factors to corn yield were respectively precipitation in growing season (PGS), rate of nitrogen fertilizer and available nitrogen contents of soil. Only when the PGS was greater than 280 mm, was nitrogen fertilizer effect statistically noticeable. The appropriate combination of nitrogen, phosphorus and potassium fertilizers increased the water use efficiency by 24.3% compared to no fertilizer treatment. Corn yield was positively correlated with the available nitrogen contents of soil too, meaning that higher soil available nitrogen contents are favorable to the increase in corn yield.