施氮肥对羊草栽培草地生产性能及品质的影响

Effects of Fertilization on Yield and Quality of Leymus chinensis Cultivated Grassland

以农菁4号羊草栽培草地为对象,研究了不同施氮期(返青期、拔节期和孕穗期)和施氮量(0kg/hm^2、60kg/hm^2、90kg/hm^2、120kg/hm^2)对羊草生产性能及品质的影响。结果表明:施氮肥有效增加了羊草的产量。其中,返青期施肥的增产效果最好,施氮量为120kg/hm^2(N3)的产量最大,为20488.9kg/hm^2;抽穗期施氮量60kg/hm^2处理的增产效果最好,为62.8kg/kg。施氮肥能够增加羊草的粗蛋白(CP)含量,降低粗纤维(CF)、酸性洗涤纤维和中性洗涤纤维的含量。拔节期施氮肥为90kg/hm^2(N2)的粗纤维含量最低,当施肥量大于90kg/hm^2时,羊草粗蛋白含量显著高于未施肥(N0)。羊草在返青期施氮肥120kg/hm^2可获得较高的产量,在拔节期施氮肥90kg/hm^2可获得较高的品质。

The effects of applying N time （turning green, jointing and booting） and N levels （0 kg/ hm2, 60 kg/hm2, 90 kg/hm2, 120 kg/hm2） on the yield and quality of Leymus chinensis Nongjing No. 4 cultivated grassland were studied. The results showed that： nitrogen effectively increased the hay yield of Leymus chinensis Nongjing No. 4. Applying nitrogen in turning green period （A1） had the best effect on increasing yield compared with the other two periods （A2 ＆ A3）, and the hay yield was the largest （20488. 9 kg/hm2） when the applying nitrogen rate was 120 kg/hm2 （Ns）; applying nitrogen at rate of 60kg/hm2 （N1） in the heading period（A3）had the best effect on increasing yield （62.8 kg/kg）. Nitrogen could increase the crude protein （CP） content, hut reduced crude fiber （CF）, acid detergent fiber （ADF） and neutral detergent fiber （NDF） content. The crude fiber （CF） was the lowest when the nitrogen was applied at the rate of 90 kg/hm2 （N2） in early jointing period（A2）. The crude protein （CP） were significantly higher when applying nitrogen rate was beyond 90 kg/hm2 （N2） than unfertilized （N0）. Applying nitrogen at rate of 120 kg/hm2 in turning green period had higher yield, and applying nitrogen at the rate of 90 kg/hm2 in jointing period had a higher quality of Leymus chinensis.