灌水对水肥一体化制种玉米产量和水分利用效率的影响

研发和推广应用高效节水技术是提升扬黄灌区制种玉米产量、支撑制种玉米产业增效和持续发展的重要途径。为了给建立制种玉米水肥一体化技术模式下的科学高效灌溉制度提供科学依据。在甘肃扬黄灌区滴灌水肥一体化条件下，研究了不同灌溉定额和灌水次数下制种玉米的产量表现和水分利用效果。结果表明，灌溉定额从2 250 m3/hm2增加到3 000 m3/hm2时，制种玉米增产幅度达33.84%，但灌溉定额高于3 000 m3/hm2并继续增大时增产效果不明显，生育期耗水量增加，水分利用效率降低明显。灌水次数从10次增加至20次时，制种玉米产量及水分利用效率均呈降低趋势，灌水次数多于15次并继续增加时，制种玉米减产显著。灌水次数和灌溉定额之间不存在互作效应。在灌溉定额偏低条件下，增加灌水次数会造成制种玉米严重减产。当生育期灌溉定额为3 000 m3/hm2、灌水次数为10次时，折合产量较高，为7 386.9 kg/hm2，较其余处理增产-2.77%～93.58%；水分利用效率最高，为17.83 kg/(mm·hm2)，较其余处理提高5.32%～78.30%；种植纯收益较高，为29 683.6元/hm2，较其余处理增加-511.8～20 675.4元/hm2；产投比最高，为3.03，较其余处理增加0.07～1.38。可见，灌水10次、灌溉定额为3 000 m3/hm2时灌溉水利用效果相对优化。

Effects of Irrigation on Yield and Water Use Efficiency of Seed Corn under the Condition of Water and Fertilizer Integration

Research and extension on efficient water-saving technologies are of great importance in increasing the seed corn yield, supporting seed corn industry efficiency enhancement and sustainable development in Yanghuang irrigated area. To provide reference for scientific irrigation system establishment under the water and fertilizer integration mode for seed corn, the yield performance and water use efficiency of seed corn under different irrigation quota and irrigation times were studied under the condition of water and fertilizer integration of drip irrigation in Yanghuang irrigated area of Gansu Province. The results showed that when irrigation quota increased from 2 250 m3/ha to 3 000 m3/ha, the yield of seed corn increased by 33.84%, however, when the irrigation quota was at or higher than 3 000 m3/ha, the results of yield increase along with the increase of irrigation quota was not significant, the water consumption increased during the growth period, and the water use efficiency decreased significantly. When the irrigation times increased from 10 times to 20 times, the yield and water use efficiency of seed corn showed a trend of decrease. When the number of irrigation times was more than 15, the yield decreased significantly along with the increase of irrigation times. No interaction effect between irrigation times and irrigation quota was detected. Especially under the condition of low irrigation quota, increasing irrigation times would reduce yield of seed corn seriously. When compared with other treatments, under the treatment of 3 000 m3/ha irrigation quota and 10 times of frequency, average seed corn yield was high which was 7 386.9 kg/ha and was increased by -2.77% to 93.58%, water use efficiency was the highest which was 17.83 kg/(mm·ha) and was increased by 5.32% to 78.30%, the net income was the highest which was 29 683.6 RMB/ha and was increased by -511.8 to 20 675.4 RMB/ha, and the production investment ratio was the highest which was 3.03 and was inceased by 0.07 to 1.38. Therefore, the irrigation water utilization efficiency was relatively optimized when irrgated 10 times at the irrigation quota of 3 000 m3/ha.