Study On Water Requirement And Optimal Irrigation System Of Jujube Under Drip Irrigation In Arid Oasis

Object:Different irrigation quota in nanjiang arid oasis region drip jujube growth,the influence of water consumption and different growth stages in Chinese jujube,further clear drip irrigation water requirement of Chinese jujube,analysis of different irrigation water for drip irrigation,jujube jujube tree crown breadth,new tip,the influence of the weight of,different irrigation quota jujube space-time change of soil moisture content,and determine the drip jujube optimal irrigation system.Methods:In the Xinjiang production and construction corps 14th Kun Yu city 224 group 5 and 7 was carried out by two years of drip irrigation jun jujube research test,test for irrigation water single factor 5 levels（The irrigation amount of W1,W2,W3,CK and W4 were 5400,5850,6300,6750 and 7200,respectively）,jujube growth period starting April until the end of October the growth period of Chinese jujube,jujube root zone soil moisture content under different moisture gradient measurement,jujube growth physiological indexes,jujube yield and water use efficiency.Results:（1）There were obvious stratification of soil moisture in the study area,which was manifested as 80-100 cm deep soil>20-80 cm root soil>0-20 cm surface soil.Jujube trees had a poor water retention effect on 0-20 cm soil surface,but a better water retention effect on 20-100 cm soil surface.The variation laws of different soil layers are similar,and they all increase first and then decrease with the passage of time.At the same time,increase the amount of irrigation water,soil moisture would migrate to deep soil to a certain extent.In flowering and fruiting stage and fruit expansion stage,the longitudinal movement range of the wetting front was mainly concentrated in 0-80 cm soil layer after irrigation,and the lateral movement range was mainly concentrated in 0-30 cm from the drip irrigation zone.（2）The ET₀ values from 2020 to 2021 are 940.38 mm and 1147.93 mm respectively.The water consumption of jujube trees in the whole growth period is 529.89-681.66mm,which is as follows:germination stage<new shoot stage<fruit maturity stage<flowering and fruiting stage<fruit expanding stage.The peak period of water consumption of jujube trees was fruit expansion period and flowering fruit-setting period,and the water consumption of jujube trees accounted for 68.95%-74.29%.In the first four growth stages of jujube,jujube trees are sensitive to water changes,and water consumption intensity of jujube trees increases significantly with the increase of irrigation amount,but there is no significant difference in water consumption intensity of jujube trees among different treatments at fruit maturity stage.The water requirement for jujube growth increased significantly from May,peaked in August,and decreased in September and October.（3）W2 treatment(5850 m³·hm^-2)had the largest crown width,the best growth in the new stem and the best growth in jujube hanging.W2 irrigation treatment had the best photosynthetic characteristics in both flowering and fruit setting stage and fruit expansion stage,which was suitable for the growth of jujube.The fruit setting rate of jujube trees in W2 and W3 treatments was 56.03%and 15.95%higher than that in CK treatment,respectively,while the fruit setting rate of W1 and W4 treatments was 17.59%and 24.13%lower than that in CK treatment,respectively.W2 treatment(5850 m³·hm^-2)was most beneficial to the fruit setting of jujube trees.The comparison of fruit longitudinal diameter and transverse diameter showed as follows:W4<W1<CK<W3<W2.Under the condition of saving 13.33%water（W2 treatment）,jujube fruit had the largest vertical and transverse diameter.The order of single fruit weight from small to large was W4<CK<W1<W3<W2,in which the single fruit weight of W1,W2 and W3 treatments increased by 9.76%,23.57%and 19.52%,respectively,compared with CK treatment,while the single fruit weight of W4decreased by 2.65%.W2 treatment had the largest single fruit weight and could be regarded as the optimal treatment under the experimental conditions.（4）The order of jujube yield from small to large is W1<W4<CK<W3<W2.The order of WUE from small to large was W4<CK<W1<W3<W2.The higher the irrigation amount was,the lower WUE was.Compared with CK treatment,WUE of W1,W2 and W3 treatments increased by 5.35%,19.66%and9.57%,respectively.W4 treatment decreased by 13.18%.Conclusion:Under the experimental conditions,the growth,yield,water use efficiency and water saving of jujube trees under W2 treatment(5850 m³·hm^-2)are the optimal irrigation treatments.The fitting function relationship showed that the most suitable irrigation amount was set as5982.10～6122.00 m³·hm^-2,and the number of irrigation was 10 times,and the fruit ripening stages were 1 time,1 time,3 times,3 times,and 2 times at the germination stage,the new shoot stage,the flowering and fruit setting stage,and the fruit expansion stage,respectively.