Management of late fruiting stage and senescence period of planting pear trees

After pear trees enter the later stage of full fruit and senescence, such as poor management, lack of fertilizer and water, excessive load, aggravation of diseases and insect pests, it will accelerate the senescence and death of pear trees, and lose the value of cultivation.

First, the performance of pear trees in the late fruiting stage and senescence period.

In the later stage of full fruit, the yield decreased year by year, the growth of new shoots decreased, the growth potential turned to moderate, and the perennial fruiting branch group weakened year by year and partially withered. Results the position moved outward obviously, the sagging degree of the backbone branch was serious and the bald phenomenon occurred in the back part. Sometimes the dorsal arch was easy to grow branches, which was easy to produce big and small years, and the resistance to diseases and insect pests weakened year by year. After entering the aging stage (after the tree age reaches 30-40 years old), the yield decreases, the absorption and transport capacity of the root system decreases, and the baldness of the inner chamber and the base of the backbone branch is aggravated. The results showed that the site was limited to the periphery of the crown, there was almost no new shoot development, and the phenomenon of senescence and death of fruiting branches became more and more serious. When the branches are stimulated (heavy pruning and pruning, mechanical injury, etc.), the latent buds are easy to sprout into overgrown branches and root tillering branches, and the trees are often incomplete and lose their cultivation value.

Second, field management in the later stage of full-fruiting and aging period:

The main results are as follows: 1. The soil fertility decreased due to the consumption of soil nutrients by trees. Therefore, sufficient organic fertilizer must be applied to maintain tree potential and yield. The main type of fertilizer is farm manure, and the amount of fertilizer should reach the standard of 1 jin of fruit and 1 jin of fertilizer. if there are more flower buds, more nitrogen fertilizer can be applied, supplemented by phosphorus and potassium fertilizer; otherwise, phosphorus and potassium are the main fertilizer, supplemented by nitrogen fertilizer. Fertilization methods, in addition to the general ditch application method, because the root system is relatively weak in this period, so we should pay attention to the depth of fertilization, do not break too many roots. The dormant period is the key period of basal fertilizer application, and it is better to apply it before defoliation after harvest. Topdressing should be carried out before flowering, after anthesis and before fruit ripening, and quick-acting organic fertilizer or chemical fertilizer, mainly phosphorus and potassium fertilizer, should be selected. Under the premise of not affecting the effect of spraying, after mixing the elements needed by fruit trees into the solution, foliar spraying is carried out, and the effect is faster.

2. Timely irrigation is best before freezing, irrigation for one time (frozen water). It can meet the need of water at flowering stage. Irrigation can be carried out according to soil moisture during the growing period. Stagnant water should be removed in time in the rainy season to prevent root system suffocation and death. After irrigation and rain, ploughing and loosening the soil should be done in time. Grass mulching or mowing mulching in pear orchard can increase soil organic matter and maintain soil moisture, which should be popularized.

3. Reasonable burden, timely flower and fruit thinning and reasonable fruit branch retention during winter pruning play an important role in maintaining tree potential. Fruit retention should be reasonably retained according to orchard management conditions (fertilizer, water, soil, etc.). It is advisable to keep one fruit with 15-20 leaves. While removing the intermediate fruit, leave no leafless fruit, residual fruit, disease and insect fruit; in the case of sufficient yield, do not leave double fruit.

4. To control the outward movement of the fruit site, making use of the characteristics that the latent buds of pear trees are easy to grow new branches, heavy retraction, eye injury, ring cutting and other methods can be adopted to solve the problems of rear baldness and fruit site relocation. For the aging tree orchard whose yield per unit area can no longer meet the production requirements, new plants should be planted between rows and plants 3-4 years in advance, or large seedlings should be cultivated outside the garden for transplanting to prepare for the renewal of the whole garden. However, we should not rush to deal with the aging trees, and then gradually eradicate the aging trees when the young trees have certain economic benefits. In the case of young and old plants in the same garden, pest control should be done well.

Third, the pruning of pear trees in the later stage of full fruit and senescence.

The main task of pruning in this period is to maintain tree potential and yield, to solve the problems of outward migration of fruiting parts, weakening and withering of fruiting branches. The amount of pruning should not be too heavy to maintain enough leaves to enhance the tree potential. For incomplete plants, it is necessary to make full use of the overgrown branches of latent buds to increase the number of branches and make the crown as complete as possible. Adopt the method of retraction and renewal, renew the drooping branch and fruit branch group, should be from the top down, from the outside to the inside, year by year light cut, not too hasty. If there are sprouting branches in the dorsal bend of the drooping branches, they can be cultivated and retracted at the front end, and the branches germinating in the wound and root can also be used properly. Results the branch group was easy to senescence and death after continuous years, so it should be carefully renewed and pruned during pruning, which could retract the weakening branches at the end to the more vigorous place at the back, and the general degree of retraction was about 2:1.

IV. Integrated control of diseases and insect pests

Prevention and control should focus on the protection of trees, especially on the control of branch diseases and insect pests, such as pear rot, pear carcass blight, ring disease and so on. For the prevention and control of other diseases and insect pests, comprehensive control can be taken according to the specific conditions of the garden, in order to protect leaves, maintain tree potential, stable yield and high quality.