Effects of nitrogen applicaton level on system productivity, nitrogen absorption and accumulation in mung bean ‖ oat intercropping system | 施氮量对绿豆‖燕麦间作系统生产力及氮吸收累积的影响

Chinese. 以白绿11号和白燕2号为材料,研究不同施氮量（0、30、60、90和120kg/hm2）对绿豆‖燕麦间作系统生产力、生物产量及氮素吸收利用率的影响。结果表明：绿豆‖燕麦具有间作产量优势,间作系统比单作系统生产力平均提高了30%。间作系统生产力、生物产量、氮素吸收率并未随着施氮量的增加而增加,不施氮或施氮量较低时,燕麦与绿豆间作通过种间氮营养互补机制在不降低产量的同时,可以获得较高的土地当量比（LER）、生物产量及氮积累量;高氮肥量和种间互作使作物发生氮素＂奢侈吸收＂,且高氮条件下,豆科固氮酶受到抑制或失去活性,发生＂氮阻遏＂。

English. This study,the effects of nitrogen application rates on the productivity,nitrogen uptake and dry matter yield were investigated in mung bean ‖ oat intercropping system. Under the condition of different fertilizer amount （0,30,60, 90 and 120 kg/hm2） ,naked oat ＂Baiyan2＂ and the mung bean ＂Bailvl 1＂ were used as the experiment materials. The results showed that, compared with sole cropping system, on average, intercropping significantly increased system productivity by 30%. The productivity,dry matter yield,and nitrogen uptake and utilization efficiency did not go up along with the increase of nitrogen application rate. Under high nitrogen fertilizer and intercropping, all nitrogen fixers have a character that they will loss ability of nitrogen fixation, called ＂ammonia repress＂, indicating that over abundant nitrogen uptake exited. Without or with lower the supply of N fertilizer, intercrops of mung bean and oat showed higher productivity,LER,biological yield, nitrogen uptake and utilization efficiency, but without influencing the total intercrop grain yield.