Effects Of Pruning Methods On The Growth And Fruit Quality Of The Trunk-shaped ’junzao’ Jujube

In order to explore the appropriate pruning method for the trunk-shaped tree shape of‘Junzao’jujube in the cultivation process of the fruiting branch group under labor-saving cultivation,,three pruning methods of the 3-year-old trunk-shaped‘Junzao’jujube（heavy truncation and cultivated touhou-branch,no pruning and cultivated touhou-branch and no cultivated 1-year-old touhou-branch）were compared in growth,canopy characteristics,photosynthetic capacity,fruit quality and yield,and It aims to provide a feasible reference for actual production.The results showed that（1）Three pruning methods have significant effects on the growth of trunk-shaped‘Junzao’jujube.When the heavy truncation and cultivated touhou-branch were placed,1-year-old touhou-branchs tend to grow thicker,but they are easy to extend when they are placed without short cut;no cultivated1-year-old touhou-branch is higher than others in leaf length,leaf width and leaf area,the chlorophyll SPAD value show that heavy truncation and cultivated touhou-branch>no pruning and cultivated touhou-branch>no cultivated 1-year-old touhou-branch.In terms of leaf nitrogen content and the number of results per plant,it show that no pruning and cultivated touhou-branch>heavy truncation and cultivated touhou-branch>no cultivated 1-year-old touhou-branch.（2）The three pruning methods had significant effects on the canopy characteristics and photosynthetic capacity of the trunk-shaped‘Junzao’jujube.The leaf area index is higher,the average leaf inclination angle is stable,and the scattering amplitude without interception is larger,and the light interception ability is stronger when the heavy and short cut branches are placed.When not truncating the stalks,The average leaf inclination is high and the amplitude is large,and the canopy has good light transmission;The canopy is small and the unintercepted scattering is high by no cultivated 1-year-old touhou-branch When the heavy truncation and cultivated touhou-branch were placed,The distribution of canopy branches and leaves was more reasonable and the net photosynthetic rate of the leaves was higher 16.92%than no cultivated1-year-old touhou-branch,It is beneficial to cultivate the fruiting branch group.（3）There was no significant difference in yield among the three pruning treatments.The titratable acid content and the soluble protein content of the fruit show that heavy truncation and cultivated touhou-branch were significantly higher than no cultivated 1-year-old touhou-branch by 0.09%and 17.92 mg·100g^-1,but vitamin C content show that heavy truncation and cultivated touhou-branch lower than no pruning and cultivated touhou-branch and no cultivated 1-year-old touhou-branch.by 7.55 mg·100g^-1,and fruit of no cultivated 1-year-old touhou-branch had good commerciality.（4）The three pruning methods had significant effects on the nutrients of some branches of‘Junzao’jujube.The C/N ratio of the no pruning and cultivated touhou-branch was significantly increased by32.95%compared with no cultivated 1-year-old touhou-branch.The C/N of the secondary branches of the1-year-old touhou-branch was significantly higher than 11.87%of its primary branches when the branches were cut heavily and placed,however the C/N of the primary branches was significantly lower by 14.92%;There was no difference in the total phosphorus and soluble sugar content of various touhou-branch,when the heavy truncation and cultivated touhou-branch.It performed well in branch nutrients when it was not placed in the same year.The soluble sugar content in the branches of the heavy truncation and cultivated touhou-branch was 3.67 g·kg^-1higher than no pruning and cultivated touhou-branch.To sum up,it is suggested to cultivate the fruiting branch group by heavy truncation,and directly cultivate center stem extension branch,and then pull the branch to expand the crown.When the primary branch or secondary branch of 1-year-old touhou-branch grows to about 6 knots,It can complete the3-year-old trunk-shaped Junjujube tree,which is more suitable for pruning and cultivation.