施氮量与密度对西南地区主栽青贮玉米品种产量和品质的影响

Effect of Nitrogen Application and Density on Yield and Quality of Mainly Planted Maize Varieties in Southwest China

以试验前期筛选适合西南地区高产优质青贮玉米品种为研究对象,采用再裂区试验设计,分别在两年三地进行试验,探究氮肥、密度、环境及其互作对青贮干物质产量、品质的影响。2018年结果表明,减氮施肥能替代传统施肥,干物质产量随施氮量的减少先增加后降低,随密度的增加逐渐升高。2019年在雅安和合川试点,减氮10%和30%与常规施氮(纯氮300 kg/hm^(2))相比,各品种干物质产量随密度增加先升高后降低,在密度82500株/hm^(2)时产量最高;在怀化试点,减氮10%处理下的干物质产量显著高于常规施氮和减氮30%处理,干物质产量随密度增加而增加。氮密互作对青贮玉米品质影响不明显。综合分析两年干物质产量及品质,在种植密度71250~82500株/hm^(2)搭配减氮10%~30%时,青贮玉米产量达到最高且品质没有降低或降低不显著。

To explore the effects of nitrogen fertilizer,density,environment and their interaction on the yield and quality of silage maize,we selected high yield and high-quality silage maize varieties suitable for southwest China in the early stage of the experiment as the research object.The experimental design of the split-split-plot was adopted,and the experiments were carried out in two years and three places.The results of 2018 showed that nitrogen reduction fertilization could replace traditional fertilization,and the dry matter yield increased gradually with the increase of density.In Ya’an and Hechuan in 2019,compared with conventional nitrogen application(300 kg pure nitrogen/ha),the dry matter yield of each variety increased first and then decreased with the increase of density,and the highest yield was obtained at the density of 82500 plants/ha.In Huaihua,the dry matter yield under 10%nitrogen reduction was significantly higher than that under conventional nitrogen application and 30%nitrogen reduction,and the dry matter yield increased with the increase of density.The effect of nitrogen density interaction on silage maize quality was not obvious.When the planting density was 71250-82500 plants/ha and nitrogen was reduced by 10%(270 kg pure nitrogen/ha)-30%(210 kg pure nitrogen/ha),the yield of silage maize reached the highest and the quality was not decreased,or the decrease was not significant.