Study On Irrigation Schedule Of Drip Irrigation Jujube In Akesu

In view of the scarce water resources, low irrigation water use efficiency of the fruitindustry in Akesu, and less methods for estimating hourly ET₀in greenhouse conditions, inorder to achieve water-saving, high yield through the water-regulated, and establish an hourlyET₀calculation model in greenhouse, this paper develop on the experiments in AkesuAgricultural Technology Demonstration Garden and in greenhouse at Yangling.The waterdeficit treatments are slight water deficit and severely water deficit at bud burst to leafingstage, slight water deficit flowering-fruit bearing stage, slight water deficit fruit speedinggrowth stage,and slight water deficit and severely water deficit at fruit maturing stage.Though the water deficit irrigation experiment,the paper analyses the effect of different waterdeficit treatments on the variation of soil moisture content, eco-physiological indicators, waterconsumption characteristics and yield, determines the suitable irrigation schedule and waterproduction function for jujube in Akesu. At the same time, comparing the similarities anddifferences of the hourly ET₀calculated by modified Penman-Monteith equation andPenman-Monteith equation in Greenhouse at Yangling, the main results of the research are asfollows:（1）The variation of soil moisture content of water deficit treatments was smaller thanfull irrigation treatment in whole growth stage. Contrast the dynamic change of the verticalsoil moisture after irrigation, the variation of soil moisture content of treatment1at bud burstto leafing stage was large on the0-50cm soil layer and small on the50-100cm, the variationof soil moisture content of treatment2and3on the0-40cm soil layer was both smaller thanfull irrigation.At fruit speeding growth stage on the0-40cm soil layer, the variation of soilmoisture content of treatment1and5was the largest and higher than both bud burst to leafingstage and flowering-fruit bearing stage.With the increase of irrigation water, waterconsumption and daily water consumption rate of jujube were increasing.（2）In whole growth stage, the variation of the chlorophyll content of all treatmentsshowed on the increase gradually, the chlorophyll content at flowering-fruit bearing stage andfruit speeding growth stage was the fastest increase. At the same growth stage, the chlorophyll content of all treatments decreased by the reduction of irrigation. In different irrigationtreatments, the leaf water potential of water deficit treatments in the overall day was less thanthe full irrigation, treatment3and full irrigation was in the greatest difference. New shoots atBud burst to leafing stage and flowering-fruit bearing stage were in the a rapid period, whichwas at fruit speeding growth stage become slow, began into the reproductive stage, differenceof new shoots between full irrigation treatment and the water deficit treatments was notobvious. Severely water deficit at bud burst to leafing stage and slight water deficit at fruitmaturing stage can decrease the weight and volume of fruits. Compared with full irrigationtreatment the water deficit treatments at different stages can increase the soluble sugar contentof fruit.（3）The relationship between yields and water consumption in whole growth stage wasparabola, and the correlation is0.9045. With water-regulated at bud burst to leafing stagereduction of yield was not obvious, at fruit maturing stage can improve yield andWUE.According to the water deficiency sensitive index of four water production functionmodels and result of analyze of all models, it showed that flowering-fruit bearing stage andfruit speeding growth stage were sensitive to water, the variation of the water deficiencysensitive index of Jensen and Stewart which were suitable for jujube in Akesu.According toanalyze it can get the best irrigation quota: the irrigation quota is370cubic meter per mu.（4）The negative values and coefficient of variation values of hourly ET₀calculated by themodified PM equation were less than those obtained by PM equation, the correlation betweenhourly ET₀calculated by the modified PM equation and the meteorological factors was verysignificant.