| Peach trees grow vigorously,and the redundant growth of branches is serious,which not only causes the canopy to be closed and affects ventilation and light transmission,which is not conducive to the formation of quality,but also significantly increases the cost of pruning labor.Paclobutrazole is commonly used in production to control the growth of new shoots,but paclobutrazole has shortcomings such as affecting the mechanical strength of branches,reducing fruit quality and long residue period,and technical measures to replace paclobutrazole control are urgently needed in production.The use of physical means such as root pruning and the new growth regulator calcium cyclic acid to control the growth of peach branches may be an effective means to replace paclobutrazole,but it has been reported less in peach production.In this experiment,three groups of treatments were set up for each of the 3-year-old early-maturing variety ’Middle Peach Purple Jade’ and the late maturing variety’Xiahui No.8’ as the test materials,DK(blank treatment),D1(four-week root pruning),and D2(two-sided root pruning),to study the effects of root pruning on peach growth and fruit quality.Using the 3-year-old ’Xiahui No.6’ as the test material and water as the control(CK),the spray concentration of 100 mg/L(T1),200 mg/L(T2),300 mg/L(T3),400 mg/L(T4)and500 mg/L(T5)calcium cyclotate was used as the test material and water as the control(CK),in order to provide a theoretical basis for controlling the growth technology of peach tree shoots.The results of the study are as follows:1.Root pruning can affect the development of new shoots and leaf photosynthetic performance of peach trees.Both D1 and D2 treatments could reduce the growth of new shoots,and compared with the control,the growth of new shoots of the early maturing variety’Chinese peach purple jade’ decreased by 27.31% and 18.03%,respectively.The growth rate of the late-maturing variety ’Xiahui No.8’ decreased by 24.83% and 24.33%,respectively,which were significantly different.D2 treatment significantly increased the net photosynthetic rate and stomatal conductivity of peach tree leaves,and the early maturing variety ’Middle Peach Purple Jade’ increased by 15.51% and 9.84%,respectively,and the late maturing variety ’Xiahui No.8’ increased by 8.27% and 10.87%,respectively.D1 treatment reduces net photosynthetic rate and stomatal conductance.D1 and D2 have less difference in transpiration rate after treatment.2.Root pruning can affect the growth and development of peach tree leaves.Both D1 and D2 treatments could increase the soluble sugar content in leaves,and the early maturing varieties ’Zhongpeach Ziyu’ and the late maturing variety ’Xiahui No.8’ treated with D2 were increased by 26.89% and 11.52%,respectively,and the D2 treatment was increased by40.68% and 24.24%,respectively,which were significantly different.Both D1 and D2 treatments could reduce leaf area index,and the early maturing variety ’Middle Peach Purple Jade’ and the late maturing variety ’Xiahui No.8’ were reduced by 7.81% and 9.93%,and the D2 treatment was reduced by 6.49% and 8.05%,respectively,which were significantly different.3.Through the determination of fruit quality,we found that after root pruning,the single fruit weight,soluble solids content,vitamin C,total phenols and flavonoids of D2 treated in the early maturing variety ’Peach purple jade’ increased by 5.33%,9.26%,13.57%,29% and19.33%,respectively,and reduced the titratable acid content by 27.59%.The processing works best.Compared with DK,the weight,hardness,soluble solids content,vitamin C,total phenols,flavonoids and anthocyanins of the late ripening variety ’Xiahui No.8’ increased by19.22%,11.54%,4.25%,15.47%,13.89%,4.96% and 4.41%,respectively,and the D1 treatment reduced the titratable acid content by 25.93%,and the comprehensive benefits were the best in D2 treatment.The results showed that the fruit quality of the tree was improved by light root pruning,and the fruit quality was improved by D2 treatment.4.After spraying different concentrations of calcium cyclic acid,it was found that different concentrations of calcium cyclic acid could inhibit the growth of new shoots.Compared with the control,the effect of spraying 300mg/L calcium cyclonic acid in the first 7days after treatment was better than spraying other concentrations of calcium cyclic acid.After 7 days of treatment,the effect of spraying 400mg/L calcium cyclic acid was better than that of spraying other concentrations of calcium cyclic acid.Different concentrations of calcium cyclic acid could increase the net photosynthetic rate of leaves,and compared with the control,the net photosynthetic rate of leaves treated with 300mg/L increased by 17.16%,which was significant,and there was no obvious difference in other concentrations.5.Spraying calcium cyclic acid can affect the growth and development of peach tree leaves.Compared with the control,the chlorophyll A content of calcium cyclic acid treated peach leaves at 100 mg/L,200 mg/L,300 mg/L,400 mg/L and 500 mg/L increased the chlorophyll A content by 4.99%,31.54%,11.89%,12.35% and 10.21%,respectively.The starch content of leaves increased by 1.59%,6.61%,12.37%,12.89% and 13.09%,respectively.6.Through the determination of fruit quality,it was found that compared with the control,compared with the control,the weight of 100 mg/L,200 mg/L,300 mg/L,400 mg/L and 500mg/L was increased by 17.71%,20.92%,10.92%,13.65% and 16.71%,respectively.Compared with the control,the contents of vitamin C treated with calcium cyclic acid at 100mg/L,200 mg/L,300 mg/L and 500 mg/L were increased by 1.79%,0.92%,3.19% and1.25%,respectively.The soluble solids content increased by 1.78%,3.39%,3.55% and 3.23%,respectively.The results showed that the fruit quality could be improved by spraying calcium cyclic acid,and the comprehensive benefits were the best in T3 treatment. |
