The Effects Of Different Pruning Methods On Growth And Fruit Quality Of Arid Dwarf Middle Stock ‘Yanfu3’ Apple Trees

Pruning is an important fruit production management technical measures and plays an important role in fruit tree growth and fruit quality.The 4-year-older dwarfing interstock’Yanfu 3’ was employed as experimental materials in a rain-fed raising area.Effects of growth rate,photosynthetic parameters,leaf quality and fruit quality were measured by setting different pruning methods(pruning amount in winter,spacing between shoots and branching angle).The results showed that:1.The degrees of winter pruning had certain influence on the growth and tree-shape culture of the ’Yanfu 3’ apple tree in arid area.Compared to CK treatment,the stem diameter of A3 treatment were increased by 23.3%.The net photosynthetic rate,leaf area,leaf thickness,leaf dry fresh ratio,fruit solids,and vitamin C increased by 22.7%,7.9%,23.7%,2.3%,7.7%,and 55.2% when the trimming was 30% of total shoots,respectively.When the amount of pruning was 30% of the total shoots,the parameters of tree structure,photosynthetic parameters and fruit quality were significant superior than other treatments and controls by analysis of comprehensive indicators.2.The different spacing of engraving bud had a significant effect on the growth of fruit trees.The results showed that trunk diameter,net photosynthetic rate,leaf area,soluble solids,and fruit shape index were increased by 20.7%,13.7%,23.1%,8.1%,and 7.1%,respectively.compared with CK treatment.Moreover,the spacing of engraving bud was 15 cm,the thickness of leaf,stomatal conductance,vitamin C and fruit weight were higher under than other treatments.And there are significant promoting effect on photosynthesis and leaf quality.3.The branching angle had an important influence on the tree-shape culture of the apple tree of ’Yanfu 3’ in the arid region.The results showed that the trunk diameter of dwarfing interstock ’Yanfu 3’ apple tree was significantly promoted when the branch angle was 95 to105.And the stomatal conductance,leaf area and dry-to-fresh ratio of the leaves treated with T3 were higher than other treatments,ncreased by 20.2%,10.8%,and 4.2% compared with CK treatment,respectively.Besides,the net photosynthetic rate and leaf thickness were increased by 29.5% and 25.0%,compared with CK.And the value of leaf SPAD,external and internal quality have been improved by treated of T3 and T4.In summary,the protoming effects was most obvious for growth and fruit quality of dwarfing interstock ’Yanfu 3’ in the arid region when the number of branches reached 30% of the total branches,the spacing of buds was 15 cm and the branch angle was 95° to 105°.