Effects of Drought at Different Growth Stages and Different Water Availabilities on Growth and Water Consumption Characteristics of Summer Maize

By the experiment for test-pits under a rain shelter,the effects of drought at different growth stages and different water availabilities on growth,water consumption,yield and water use efficiency(WUE) of summer maize were studied.The results showed that drought at different growth stages would inhibit the increase of plant height and leaf area index (LAI).The more severe the drought hit,the smaller the plant height and LAI.Suitable for water treat-ment,the plant height and LAI were growing better than the other treatments.The yield showed the first rise after falling trend with drought time occurring later.The output reduction in seedling stage with the light-water deficit treatment was the least,that was 9.88%,while the grain number per spike in tasseling stage with the severe water deficit treatment was the lowest,was 349.98,and then the yield reduction was the greatest,was 32.67%.The water consumption of the severe water deficit at jointing stage treatment was the lowest at 258.09 mm.Any growth stage of drought-hit,its days as the water consumption decreased the severity of drought.Through the yield and water con-sumption of summer maize analysis,both showed a good relationship between the quadratic curves.WUE of the light-water deficit at jointing stage was the highest,2.202 kg/m 3,followed by treatment of dry weight in seedling stage.And because of the magnitude of production decrease was more than water-saving in late stage,WUE decreased.Fi-nally,according to the results of yield and WUE in different treatments,properly reduce the limit of soil moisture for water-saving and high-yield in summer maize was put forward in this paper.