鲜食甜玉米需水规律及节水灌溉制度研究

【目的】研究鲜食甜玉米需水量、需水规律及节水灌溉制度,指导其科学合理灌溉。【方法】连续开展2 a鲜食甜玉米田间灌溉试验,以群众高产种植经验为试验处理,在试验小区内安装智墒和云智能气象站采集土壤墒情、气象数据。分析了甜玉米全生育期土壤水分动态变化规律;计算了甜玉米逐日需水量和作物系数,分析了其需水量规律;针对实际灌溉中存在的问题,对甜玉米灌溉过程中土壤含水率上下限进行了优化。【结果】甜玉米土壤水分变化主要集中在10～30 cm之间,根系最大吸水深度为50 cm;2016—2017年甜玉米全生育期需水量分别为197.7 mm和212.9 mm,平均需水强度分别为3.0 mm/d和3.1 mm/d;需水强度呈现抽雄吐丝期灌浆乳熟期拔节期苗期的规律;甜玉米作物系数(Kc)苗期最小,抽雄吐丝期最大,2 a全生育期Kc平均值分别为0.63和0.67;经过灌溉制度优化,甜玉米全生育期灌水4次,净灌溉用水量较实际分别减少31.87%和33.97%。【结论】甜玉米需水量较小,需水规律和普通玉米相似,农业生产中应根据降雨情况适时补充灌溉。

Water Consumption of Sweet Corn and Its Water-saving Irrigation Strategies

【Objective】Cultivation of sweet corn has increased over the past decades in some areas of China, but its demand for water and the associated irrigation strategies are poorly documented. The objective of this paper is to plug this knowledge gap.【Method】A two-year field experiment designed based on the principle of achieving high yield was conducted. During the experiment we measured the change in soil moisture and meteorological factors, and used them to calculate water requirement, water consumption and crop coefficient(kc) of the crops. These help us to optimize the irrigation strategy for sweet corn production.【Result】The water requirement, daily water consumption during the growth season of the sweet corn in 2016 and 2017 were 197.7 and 212.9 mm, 3.0 mm/d and 3.1 mm/d respectively. The daily water consumption varied with growth stage, being highest in the tasseling stage and least in the seedling stage. The average crop coefficient in 2016 and 2017 was 0.63 and 0.67, respectively, and the optimal calculation showed that changing irrigations times to four could reduce irrigation water by 31.84% to 33.97% compared to the currently used irrigation strategy.【Conclusion】Water requirement of the sweet maize was low and its water consumption was similar to normal corn. Appropriate irrigation is essential to safeguarding its production.