The Technology Optimization Of Water And Fertilizer Management On Dwarf Close-planting Jujube With Drip In Extremely Arid Region

In this paper, a total of eight field trials of Hami jujube are designed under differentfertilizer treatment programs. The growth and physiological changes of close planting jujubeunder different fertilizer combination treatments, as well as the climate field changes causedby drip irrigation are monitored. Based on these measured data, analysis is made: waterconsumption regularity of jujube under different irrigation treatments; the field microclimateeffects for growth index of jujube during flowering and fruiting; the effects of water andfertilizer on drip dwarf close jujube physiological characteristics, yield and fruit quality.Based on the experiment, conclusions can be listed as follows:(1) The water consumption coefficient of drip dwarf close jujube varies in differentgrowth periods, in order of most coefficient,it goes: white-mature period, ripe peroid, shootand fruit growing period, flowering and budding period. The increased drip irrigation is goodfor shoot growth of dwarf close jujube, among them, the larger amount of irrigation (Ctreatment) is most obvious, but too much irrigation (D treatment) is not conducive to thegrowth of new shoots.(2) The drip irrigation can increase field relative humidity. Compared to regional average,field relative humidity increased30%to50%after3-4days. The irrigation amount increasesmore, soil temperature in each layer depth dropped lower. The soil temperature of the largestirrigation amount (D treatment) is1.3℃to2.1℃lower than the minimum irrigation amount(A treatment).(3) Different fertilizer and water combinations treatments have different effects onphotosynthetic characteristics of dwarf close jujube. Stomatal conductance under lowerfertility and smaller irrigation amount reachs a larger value in the morning, while under higherfertility and a larger irrigation amount achieves greater values in the afternoon, among them,C2treatment handles the maximum stomatal conductance with average daily value0.17mol/m2s; high irrigation and fertilizer make the leaf maintain a high transpiration rate, andthen slow down or shorten the " lunch break " level or time; on the contrary, water has lessimpact for leaf photosynthesis under low irrigation condition. C2treatment has the highestphotosynthetic rate than others.(4)Under the same circumstances, dwarf close jujube with high irrigation level hadhigher yields, among them, C2treatment reached a maximum as534kg/667m2. Drip irrigationon increasing production showed a positive effect, but when the irrigation amount increasedto992mm/667m2,jujube production begins to decrease. Fertilizer and water combinationtreatments significantly affect jujube soluble sugar content. The highest soluble sugar contentis34.3%in C2treatment.(5) Stomatal conductance, transpiration of drip dwarf close jujube showed nosignificant correlation with jujube production and soluble sugar content, but waslevant to photosynthesis; resemble relative humidity of several field trials and operations such as shooterasing and flower thinning by farmer made the air relative humidity have less impact onflowering and fruit setting rate; soil temperature didn’t have effect on yield significantly.(6) According to the results, the dwarf close jujube drip system is optimized as appendix.