不同灌溉制度对覆膜春玉米的耗水规律及产量的影响

Study on effects of different irrigation treatments on evaportranspiration and yield in spring maize

研究了不同灌水定额和灌水次数处理下覆膜玉米的耗水规律和产量,试验结果表明：灌溉定额相同时,灌水次数的变化对产量有较大影响;灌溉次数较多的处理土壤平均含水率波动幅度较小,土壤水分能保持在一个比较稳定的范围。相同的灌水次数下,适当增加灌溉定额在一定程度上可增加作物产量,但超过一定值之后,产量并无显著提高。玉米的耗水量随着灌溉水量的增加而增加,玉米在拔节-抽雄、抽雄-乳熟期的耗水量最大,对水分亏缺最敏感,是需水关键期。水分利用效率随着灌溉量的增加而减少。

A study is made on the water-consuming law and yield of spring maize under treatments of different irrigation quota on each application and frequcency.The experimental results show that with the same irrigation quota,irrigation frequency affects significantly maize yield and soil water content fluctuation of high irrigation frequency treatment changes more slowly than that of low irrigation frequency treatment,and soil water variation keeps in a stable range.With the same irrigation frequency,the yield improves with irrigation quota in some scope.Water consumption increases with irrigation quantity,the high soil water consumption time in the whole growing period are jointing～tassel emergence and tassel emergence～milky maturity stages.In these stages spring maize is sensitive to water stress.They are the critical stages of water requirement,and WUE decreases as the irrigation quantity increases.