灌溉定额和绿肥交互作用对小麦/玉米带田产量和养分利用的影响

Effects of irrigation quota and green manure interaction on crop yield and nutrition utilization in the wheat/corn intercropping system

【目的】研究灌溉定额、绿肥及其交互作用对河西绿洲灌区带田小麦、玉米产量和养分利用的影响,探寻适合灌区带田的水肥管理模式。【方法】试验采用裂-裂区设计,主区处理为灌溉定额,设三个水平为4500、6000和7500 m^3/hm^2;裂区处理为绿肥,设两个水平为不种绿肥和种植绿肥;裂-裂区处理为化肥,设两个水平,为不施化肥和施用化肥,化肥处理氮、磷、钾肥料用量分别为N 525 kg/hm^2、P2O5 150 kg/hm^2、K2O 90kg/hm^2。【结果】与4500 m^3/hm^2的灌溉定额相比,6000 m^3/hm^2和7500 m^3/hm^2的灌溉定额极显著增加了小麦和玉米的籽粒产量及其收获指数,增加了小麦和玉米籽粒的氮磷钾吸收量及其养分收获指数,小麦籽粒产量形成的氮生理效率和玉米籽粒产量形成的氮磷钾生理效率;极显著降低了小麦百公斤籽粒氮需求量和玉米百公斤籽粒氮磷钾需求量。绿肥种植与否对小麦、玉米籽粒产量均没有显著影响。种植绿肥极显著降低了玉米籽粒的收获指数和钾收获指数。灌溉定额4500 m^3/hm^2与种植绿肥交互作用下,玉米磷收获指数最低;灌溉定额6000m^3/hm^2与种植绿肥交互作用下玉米磷收获指数最高。种植绿肥处理显著增加了玉米百公斤籽粒氮磷钾需求量,显著降低了玉米百公斤籽粒磷钾生理效率。4500 m^3/hm^2灌溉定额下种植绿肥进一步加剧了干旱的胁迫程度,导致玉米百公斤籽粒氮、磷需求量显著增加,对钾的需求量极显著增加,磷生理效率显著下降,钾生理效率极显著下降。【结论】灌溉定额是河西绿洲灌区带田小麦玉米籽粒产量和收获指数、籽粒氮磷钾吸收量和氮磷钾收获指数、百公斤籽粒氮磷钾需求量和氮磷钾生理效率的决定因素。亏缺灌溉定额(4500 m^3/hm^2)下,种植绿肥会降低小麦/玉米带田籽粒产量及肥料利用效率。在6000 m^3/hm^2的灌溉定额下,建议河西绿洲灌区小麦/玉米带田应配合种植绿肥,提高产量和肥料效益。

【Objectives】Effects of irrigation quota, green manure plantation and their interaction on crop yield and nutrient utilization were studied in wheat/corn intercropping system in Hexi oasis irrigation area to identify an appropriate water and fertilizer management mode.【Methods】The experiments was conducted in a split-splitplot design with irrigation quotas (4500, 6000 and 7500 m^3/hm^2) as the main plots, and green manure (planting and not planing green manure) and chemical fertilizer (fertilizer and no fertilizer) as the sub?sub plots, respectively. The chemical fertilizer treatments were applied with N 525 kg/hm^2 , P2O5 150 kg/hm^2, K2O 90 kg/hm^2 .【Results】Compared with irrigation quota of 4500 m^3/hm^2, 6000 m^3/hm^2 and 7500 m^3/hm^2 significantly increased grain yield and harvest index, grain NPK uptake and NPK harvest index, N physiological efficiency for grain yield formation of wheat, NPK physiological efficiency for grain yield formation of corn and significantly decreased N requirement for 100 kg of wheat grain yield formation and NPK requirement for 100 kg of corn grain yield formation. Green manure had no significant effect on wheat and corn grain yield. Green manure significantly decreased the harvest indexes of corn seed and K. 4500 m^3/hm^2 + green manure and 6000 m^3/hm^2 + green manure had the lowest P harvest index and highest P harvest index for corn, respectively. Green manure significantly increased the NPK requirement for 100 kg of corn grain yield formation and significantly decreased the PK physiological efficiency for corn grain yield formation. Planting green manure under 4500 m^3/hm^2 irrigation quota further intensified the drought stress and induced a significant increase in NPK requirement for 100 kg of corn grain yield formation and a significant decrease in PK physiological efficiency for corn grain yield formation.【Conclusions】Irrigation quota is the determinant for the grain yield and harvest index, NPK uptake and NPK harvest index of grain, the requirement of NPK for 100 kg of grain production and the physiological efficiency of NPK fertilizers for grain yield formation of wheat and corn in wheat/corn intercropping system of Hexi oasis irrigated area. Under deficit irrigation quota of 4500 m^3/hm^2, planting green manure would lead to decreased wheat and corn production and fertilizer use efficiencies in Hexi oasis irrigated area. If the irrigation quota of 6000 m3/hm^2 is possible, green manure is recommended for the belt production of wheat and corn in Hexi oasis irrigated area.