How to renew the old apple-pear garden? Renewal and renovation Technology of Old Apple Pear Garden

How to renovate apple pear orchard? Renovation Technology of Old Apple Pear Orchard

Fund projects: Science and Technology Innovation and Entrepreneurship Project for Returned Overseas Students in Jilin Province (2013), Modern Agricultural Industry Technology System Construction Project (CARS-29).

1 thinning

The spacing of planting plants in orchards built in 1990s was 2.5m×6~ 7m, and the cross among trees in orchards without thinning was serious, so thinning should be carried out gradually. The tree vigor can be controlled and the fruit can be produced normally by thinning or retracting the crossing or overlapping branches extending to the trees and making the main branches or lateral branches extending to the rows bear more fruit. After 3 to 4 years, the method is implemented step by step until the normal expansion of the crown of the permanent tree is not affected.

2 Tree transformation

The original trunk is two-layer shape, which is laborious and laborious, and the yield is also low. When transforming, the second layer is removed directly, and the single-layer open-center shape is changed, or the stumps 30~40cm are reserved when cutting off, and the sprouted strong branches are cultured into about 2.5 m central trunk and changed into inverted umbrella shape, which can effectively solve the problems of closed canopy and poor ventilation and light transmission in the crown.

3 Update pruning

3.1 main branch regeneration

The main branches weakened by rot or tree vigor can be retracted to the position with strong branches and strong buds, and the vertical branches on the back sprouted at the base can be directly used to stretch to about 45° and slowly released. In the second year, the extended branches are moderately truncated (about 40cm), the competitive branches are thinned out, and the angle is opened by about 70°. The upper branches on the back are removed, and other branches are slowly released without cutting (Figure 1). In the third year, about 30cm of extended branches were cut off, the strong buds on the outer side of the cultivated branches were cut short, the over-dense branches were thinned out, and the other branches could be cultured into fruiting branch groups.

Fig. 1 Regeneration of backbone branches

3.2 collateral regeneration

The lateral branches with bare belt longer than 50cm due to aging or weakening of tree vigor due to rot and other reasons and reduced fruiting parts shall be renewed. At the base of lateral branch, select strong annual branch or strong annual upright branch or inclined branch (diameter> 1.3cm) at 50cm from trunk, slowly put or lightly cut the head (about 10cm) and then pull the branch 45°. In the second year, more than 70% of medium and short fruit branches can be cultivated, with 2~3 fruits per branch, and the rest can be thinned. In the third year, the full lateral branches with diameter> 3cm and length of about 1.5m can be cultivated. From the third year, the fruit yield can be increased year by year, and the angle will naturally open.

3.3 renewal of branch groups

A fruiting branch group is reserved every 40cm on both sides of the main branch and the lateral branch, distributed in disorder, and the over-dense annual branches are thinned out. 1-year-old branches cultured as fruiting branch groups are reserved and slowly released without cutting; the flowering branch groups in the second year are flattened and begin to bear fruit; and for the excessively long fruiting branch groups, retraction pruning is carried out to avoid crossing of branch groups. For the thin and weak branch group, it can be retracted to the upright and full bud or thinned out, and the fruiting branches can be cultured by using several branches around the saw mouth in the next year. The upright and vigorous branches can be thinned out, and the oblique and moderate branches can be reserved for the fruiting branch group culture (Figure 2). The moderate branch group adopts the methods of cutting and slow combination to achieve moderate growth and not bald at the base.

Fig. 2 Fruiting branches sprouting from main branches

4 Configuration of pollinating trees

Most orchards in Yanbian area were not planted or planted less pollinated trees when they were established, and some orchards were changed to main varieties because of low economic benefits of pollinated trees, almost all relying on artificial pollination. However, with the increase of artificial cost and the increasingly serious phenomenon of artificial shortage, it is necessary to configure pollination trees. In order to solve this problem, the method of high-grafting pollinated branches is adopted. The grafting period is early April, and the annual branches in the middle and upper parts of the crown are high-grafted pollinated branches. One plant is grafted with 3~4 pollinated branches, and the survival rate is also high. The second year can bloom and play the role of pollinated trees (Figure 3). Pollinating trees preferred to extend fragrant pear, there are traditional Korean pear or Xie Huatian and so on.

Fig. 3. Pollinated branch of high grafting

5 Integrated pest management

The management of dormancy period and initial stage of occurrence was done well, and the economic and effective purpose was achieved. Before and after Qingming, the overwintering adult of P. pyriformis was sprayed with 100~200 times of oil emulsion at its peak period of hibernation, which effectively reduced the number of overwintering adults. The 5°Be sulfur mixture was sprayed at the initial bud stage to control the newly hatched nymph and eggs of P. pyriformis, and at the same time, it played a role in controlling the conidia of leaf marks and bud base overwintering and clearing the garden. The nymph of Psyllid and the initial occurrence of Scab could be effectively controlled by spraying spiroethyl ester and difenoconazole at the beginning of petal shedding. At the same time, biological control of pear fruit borer was carried out by using hanging pear fruit borer deflection silk, and then related pest control was done according to climate change.

6 Fertilization management

Base fertilizer is applied in early spring and chemical fertilizer is applied in mid-July. According to the recommendation of "expert system of balanced fertilization of pear trees" developed by professor Zhu Liwu of Anhui Agricultural University, the balanced fertilization was carried out. Pure nitrogen was applied 0.4~ 0.6 kg per 100kg fruit, and the ratio of nitrogen: phosphorus: potassium was 2∶1∶2. The fertilizer amount was reduced, the tree vigor was stabilized, and the purpose of improving quality and increasing efficiency was achieved.