Research On The Key Technology Optimization Of Transplanting Container Well-branched Trees In Replant Cropping Field

Baishui County,Shaanxi Province,as a high-quality apple producing area in China,is now facing the problems of orchard aging,tree weakness,apple yield and fruit quality reduction.At present,nearly 1/3 of the orchard area is facing the current situation of continuous cropping of apples.There are many studies on continuous cropping obstacles,and the transplanting of Apple container seedlings is one of the main methods to improve this problem.In this experiment,the 4-year-old dwarf rootstock"Changfu No.2"was used as the test material to determine the appropriate seedling container material and soil organic matter ratio,and the 5-year-old container seedlings were transplanted to the field for aboveground and underground treatment,so as to optimize some key technologies for the establishment of large seedlings garden.In order to further weaken the impact of continuous cropping obstacles on the initial stage of orchard construction,achieve early fruit and high yield,and provide scientific guidance for the healthy and sustainable development of orchard ecological environment,the following conclusions are drawn:1.The non-woven bag and PVC root restrictor were used as containers to prepare substrates D,E and F respectively.A total of 6 experimental treatments were combined.The2-year-old dwarf self rootstock"Changfu 2"was used as the test material,and the data were collected after 2 years of cultivation.The contents of soluble solids,titratable acid,fruit hardness,fruit weight,fruit number per plant,nitrogen,phosphorus and potassium in soil and roots were determined.The results showed that using different containers,there was no significant difference between the experimental treatments and the control（CK）in the internal quality of fruit.In terms of single fruit weight and single plant yield,the non-woven substrate e was higher than other treatments,and the substrate D and F had no significant difference,both higher than the control（CK）.Under the same substrate,the contents of root nitrogen,phosphorus and soil phosphorus of non-woven bags were slightly higher than those of PVC root restrictors,and there was no significant difference between non-woven bags and PVC root restrictors in the contents of soil nitrogen,potassium and root potassium,which were higher than those of the control（CK）.In conclusion,the combination of non-woven bags and substrate e was the most suitable for cultivating apple seedlings.2.After the container seedlings of apple were transplanted to the field,three different pruning（W,Y,Z）and control（CK）were used for aboveground treatment to measure the amount of flower buds,leaf growth,leaf photosynthesis,internal quality of fruit,yield and so on.The results showed that W was the best in flower bud differentiation,leaf growth and leaf stomatal conductance,Z was the best in leaf net photosynthetic rate,transpiration rate and intercellular CO₂concentration,y was the best in single fruit weight and single plant yield,but there was no significant difference in fruit quality between different pruning treatments and the control.Compared with CK,the three pruning treatments increased in flower bud amount,leaf growth,leaf photosynthesis and yield,and there was no significant difference in fruit quality.In conclusion,W pruning is the most suitable for promoting plant leaf growth and photosynthesis,and Y pruning is the most suitable for increasing yield.3.After the apple container seedlings were transplanted to the field,the underground microbial fertilizer was treated with three treatments（L,M,N）and the control.The amount of flower buds,leaf growth,leaf photosynthesis,fruit internal quality,yield,and the contents of nitrogen,phosphorus,and potassium in some parts of the plant were measured.The results showed that N had the highest amount of flower buds,and the contents of nitrogen,phosphorus and potassium in flower buds were the highest;There was no significant difference in leaf area,chlorophyll content and shutter weight among different bacterial fertilizer treatments;N was the highest in net photosynthetic rate,transpiration rate and stomatal conductance.Intercellular CO₂concentration was second only to L,and there was no significant difference.L and M had no significant difference in four indicators of photosynthesis,but they were slightly better than the control treatment;In the internal quality of fruit,there was no significant difference between the three bacterial fertilizer treatments and the control treatment.In the single fruit weight and single plant yield,the three bacterial fertilizer treatments were significantly higher than the control treatment,in which N was the highest,and significantly higher than L and M;Among the contents of nitrogen and potassium in leaves,the content of N was the highest,and the content of L was the highest among the contents of phosphorus in leaves;Among the contents of soil nitrogen and phosphorus,N was the highest,and m was the highest among the contents of potassium;Among the contents of nitrogen and potassium in root system,N was the highest,and M was the highest.In conclusion,applying L and M bacterial fertilizer at the same time is most suitable for plant growth and yield.