减施氮肥对不同密度夏玉米产量和干物质积累特性的影响

Effect of Nitrogen Fertilizer Reduction on Yield and Dry Matter Accumulation in Different Planting Densities of Summer Maize

以夏玉米品种郑单1002为材料,采用两因素随机区组设计,设4个施肥(N1,复合肥225 kg/hm^(2);N2,复合肥180 kghm^(2);N3,控释肥180 kg/hm^(2);N4,复合肥180 kg/hm^(2),有机肥1 500 kg/hm^(2))和两个密度(D1,6万株/hm^(2);D2,7.5万株/hm^(2))处理,研究减施氮肥对不同高密植夏玉米产量和干物质积累等方面的影响。结果表明,D2处理显著提高夏玉米产量24.74%,两个密植条件下N3和N4处理均未造成显著减产。D2处理显著提高吐丝期和成熟期及花后干物质积累量,降低花后干物质积累量对子粒的贡献率,减氮处理对干物质积累特征均无显著影响。N2、N3和N4处理显著提高两个密植夏玉米氮肥偏生产力16.00%~22.90%,仅D2N4处理显著提高氮肥农学利用效率16.32%。夏玉米在75 000株/hm^(2)高密植水平,施氮180 kg/hm^(2)(减氮20%)配施有机肥可达到高产高效的生产目标。

A two-factor randomized block test design was conducted with Zhengdan 1002, which analyzed the grain yield and dry matter accumulation of summer maize. The results showed that, D2 increased summer maize yield by 24.74%, significantly. And N2 declined yield of summer maize in this planting density. While the treatments of N3 and N4 had no significant influence on the yield of summer maize both in D1 and D2 planting densities.D2 significantly increased dry matter accumulation of silking and maturation stages, and the amount of dry matter after anthesis, while it decreased contribution proportion of post-anthesis dry matter to grain. The influences of N2,N3 and N4 treatments had no significant different with N1 on dry matter accumulation characteristics. In additionally, treatments of N2, N3 and N4 significantly increased nitrogen partial factor productivity by 16.00%-22.90% under two planting densities, while the nitrogen agronomy efficiency only obtained significantly higher increased by16.32% in the treatment of D2 N4. In conclusion, summer maize could achieve high yield and high efficiency aims of 75 000 plant/ha planning density and nitrogen fertilizer reduction by 20%(180 kg/ha) combined application with organic fertilizer.