氮肥对北疆滴灌复播青储玉米光合特性及养分利用的影响

为了解氮肥对北疆滴灌复播青储玉米生理指标的影响，提高氮肥利用效率，通过田间小区试验，研究了一管一行毛管布置模式下，不同氮肥处理（100、170、240、310、380 kg?hm －2）对复播青储玉米光合特性、土壤铵态氮分布的影响。结果表明，不同氮肥处理条件下复播玉米叶片净光合速率、蒸腾速率日变化曲线均呈单峰型；土壤铵态氮含量总体上随施氮量的增加先减少后增加；产量随施氮量的增加先增加后减小。综合分析认为，一管一行毛管布置模式下，240 kg?hm －2的施氮量处理下水氮耦合效果最佳，土壤铵态氮含量总体最少，产量与叶片水分利用效率最高，净光合速率较高。

Effects of nitrogen fertilizer on the photosynthetic characteristics and nutrient utilization of drip irrigated silage maize by sequential cropping in north Xinjiang

In order to investigate the effects of nitrogen (N) fertilizer on the physiological indexes of drip irrigated silage maize by sequential cropping in north Xinjiang, to increase N fertilizer utilization efficiency, through the field plot experiments have researched the effects of photosynthetic characteristics and soil NH₄⁺-N distribution under the layout pattern of one row with one lateral pipe and different N fertilizer treatments (i.e., 100, 170, 240, 310 kg·hm^-2 and 385 kg·hm^-2). The results showed that: For different N fertilizer treatment condition, the daily change curves of the net photosynthetic rate of the leaves and transpiration rate of the sequential cropping maize displayed a single peak type. Holistically, soil total NH₄⁺-N content decreased at first and then increased with increasing the N application. The yield increased at first and then decreased with increasing N application. Through the comprehensive analysis, we think under the layout pattern of one row with one lateral pipe, the N fertilizer application treatment of 240 kg·hm^-2 was the best effect of water-N coupling with the lowest soil total NH₄⁺-N content, highest yield and water use efficiency of the leaf, and a relatively high net photosynthetic rate.