施用不同氮肥对盐碱地湖南稷子生产性能以及养分吸收的影响

为探讨盐碱地湖南稷子(Echinochloa frumentacea)高效生产的最佳施氮种类和施氮量，采用单因素随机区组设计，通过在湖南稷子拔节期设置不施肥(CK)、尿素和硫酸铵(N1,N2)轻施肥(F1:50 kg·hm^-2)、中施肥(F2:100 kg·hm^-2)、重施肥处理(F3:150 kg·hm^-2),研究不同氮肥和施氮水平下湖南稷子田间农艺性状、养分吸收及氮肥利用率的变化，探讨盐碱地湖南稷子实现高效生产的适宜氮肥和施氮量。结果表明：与对照相比，施氮量为F2和F3时能够显著提高盐碱地湖南稷子产量及氮磷钾吸收量(P<0.05),植株不同部位氮含量上升，施氮量F3时能够显著提高氮肥利用效率(P<0.05),且同一施氮量下追施硫酸铵后湖南稷子产量、养分吸收及氮肥利用率均高于尿素。综上所述，氮肥追施量在150 kg·hm^-2时，有利于盐碱地湖南稷子的产量的提升和养分的吸收，且同一条件下追施硫酸铵较追施尿素效果显著。

Effects of Different Nitrogen Fertilizers on Performance and Nutrient Uptake of Echinochloa frumentacea in Saline-alkali Land

In order to explore the optimal type and amount of nitrogen application for the efficient production of Echinochloa frumentace in saline-alkali land,a single factor randomized block design was used. No fertilization (CK),light fertilization,medium fertilization,and heavy fertilization with urea and ammonium sulfate (N1,N2) were set in the jointing stage of Echinochloa frumentace (F1:50 kg·hm^-2,F2:100 kg·hm^-2,F3:150 kg·hm^-2),to study the changes in agronomic traits,nutrient uptake and nitrogen use efficiency of Echinochloa frumentace under different nitrogen and nitrogen application levels,and to explore the optimal nitrogen and nitrogen application rates for efficient production of Echinochloa frumentace in saline-alkali land. The results showed that:Compared with the control,nitrogen application rates of F2 and F3 significantly increased Echinochloa frumentace yield and nitrogen,phosphorus,and potassium uptake in saline-alkali land of Echinochloa frumentace (P<0.05),and nitrogen content in different parts of the plant increased continuously. The nitrogen application rate of F3 significantly increased nitrogen use efficiency (P<0.05). The yield,nutrient uptake,and nitrogen use efficiency of Echinochloa frumentace were higher than those of urea at the same nitrogen application rate. In conclusion,when the topdressing amount of nitrogen fertilizer was 150 kg·hm^-2,it was beneficial to increase the yield and nutrient absorption of Echinochloa frumentace in saline-alkali land,and the topdressing effect of ammonium sulfate was more significant than that of urea under the same condition.