| Popis: |
【Objective】Rainfalls in the growth season of summer maize in most areas in northern China are insufficient to meet its demand, and supplementary irrigation is thus required. The purpose of this paper is to investigate the efficacy of different hose-micro-sprinkler irrigation amounts at improving yield and water use efficiency of the maize. 【Method】The experiment was conducted in 2018—2019 at a field, with the four irrigation amounts determined by topping up the soil water in depth of 0~10 (W10), 0~20 (W20), 0~30 (W30) and 0~40 (W40) cm to the field capacity at sowing, beginning of jointing and tasseling stages, respectively. The traditional border irrigation was taken as the control (CK). During the experiment, we measured plant growth, yield components, evapotranspiration and water use efficiency (WUE) of the crops in each treatment. 【Result】With the increase in soil depth used to determine the irrigation amount, the plant height, leaf area index (LAI), aboveground dry biomass and grain yield either increased monotonically or concavely. After the soil reference depth exceeded 20 cm, the efficacy of increasing irrigation at improving crop growth declined. Among all treatments, W20 gave the highest value for all four measured indicators. Irrigation amount impacted both evapotranspiration and WUE at significant level, with the evapotranspiration increasing while the WUE decreasing with irrigation amount. No significant difference in grain yield we found between W20, CK and W40 treatments, and compared to the CK and W40, W20 reduced irrigation amount and water consumption by 47.33%~54.73% and 9.86%~13.85% respectively, with its WUE increasing at significant level by 11.48%~19.26%. 【Conclusion】Considering irrigation amount, grain yield, evapotranspiration and WUE, our results suggested that topping up soil water in the depth of 0~20 cm by the hose-micro-sprinkling irrigation to the field capacity at sowing, beginning of the jointing and tasseling stages respectively, was most effective. |
