包膜尿素对夏玉米产量及碳氮代谢的影响

Effect of Coated Urea on Grain Yield and Carbon-nitrogen Metabolism of Summer Maize

以玉米杂交种郑单958为材料,研究基施包膜尿素(120kg/hm2和90kg/hm2纯N,下同)和分施普通尿素(1:1和1:2:1的比例,总量均为120kg/hm2)对夏玉米产量、产量构成、干物质生产及碳氮代谢的影响。结果表明,基施包膜尿素120kg/hm2和分施(1:2:1)普通尿素效果基本一致,在子粒产量、穗粒数、生物产量及氮素累积量等方面均显著优于基施包膜尿素90kg/hm2和分施(1:1)普通尿素。前二者的子粒干物质和氮素累积主要来源于灌浆期叶片的光合生产和根系的吸收,表明基施包膜尿素120kg/hm2和分施(1:2:1)普通尿素,均有利于增大并延长叶片的光合生产能力和根系的吸收能力。另外,乳熟至灌浆中期,包膜尿素处理的植株营养器官总糖含量处于较合理的水平。

The objective of this experiment was to study and evaluate the effects of basal application coated urea and split application （1 ： 1 and 1 ： 2 ： 1） common urea under three application rates（0, 90 and 120 kg/ha） on yield and its components, dry matter production and carbon-nitrogen metabolism of summer maize cuhivars, Zhengdan958, and to provide some beneficial references for ameliorating the fertilization techniques and increasing crop yield in this area. The main results showed that effect of grain yield, kernel number, dry matter and nitrogen accumulation on sum- mer maize of basal application coated urea and split application （1 ： 2 ： 1） common urea treatments were close and they were bigger than other treatments, especially during the late growth stage. The main source of dry grain weight and N accumulation amount of the two advantage treatments were photosynthesis and root absorbed in milk stage, respectively. So we could conclude that the capacity of leaves photosynthesis and root absorbed was improved by these two treatments. Meanwhile the results also suggested that total content of soluble sugar and starch in leaf, stem and sheath had reached a suitable and lower value from dough to medium milk stage.