(1) Thinning includes thinning in winter and thinning in summer, and branches are cut off from the base. The result of thinning is that the number of branches in the crown is reduced, which has the functions of enhancing ventilation and light transmission, improving photosynthetic efficiency, promoting flowering and fruiting, and improving fruit quality. Severe thinning will weaken the growth of the whole tree or local branches, while thinning fruit branches will strengthen the growth of the whole tree or local branches. This is because fruit consumes less nutrition, which is more conducive to the supply of roots and the growth of new shoots, so that growth and fruiting can be carried out at the same time, and the purpose of bearing fruit every year can be achieved. Thinning is often used in production to control overgrowth, thinning out strong overgrowth, overgrowth, drooping branches, crossed branches, merged branches and crowded branches around. Thinning can remove old branches, dead branches, diseased branches and insect branches, reduce nutrient consumption, concentrate nutrients, promote tree growth and enhance tree vigor.

(2) Short cutting is also called short cutting, that is, cutting off a part of 1 annual branch or single branch. The principle is "strong branches stay short and weak branches stay long". It can be divided into light cutting (cutting off 1/4 ~ 1/3 branches), medium cutting (cutting off 2/5 ~ 1/2 branches), heavy cutting (cutting off 2/3 branches) and extremely heavy cutting (cutting off 3/4 ~ 4/5 branches). Extremely heavy cutting has the greatest stimulation to branches, and generally only 1 ~ 2 branches are produced after cutting. Short cutting has the function of strengthening and changing the dominant position of the top, which is beneficial to the regeneration and rejuvenation of the branch group and adjusting the balance relationship between the main branches. It can enhance the growth potential, reduce the growth amount, increase the number of functional branches and leaves, and promote the nutritional growth of new shoots and new trees. The accumulation of photosynthetic products decreases, which is not conducive to the formation and fruiting of flower buds. Short cut is rarely used for pomegranate pruning, but only for the regeneration and rejuvenation of old and weak trees and the shaping of young trees.

(3) Shrinkage cutting is also called retraction, that is, cutting perennial branches to suitable branches. Because the root system has not moved for a period of time after contraction, the remaining branches and buds get more nutrition and water, so it has obvious growth promotion effect, which is conducive to the renewal and rejuvenation of tree potential, and promotes flower bud differentiation and flowering and fruiting. For the whole tree, due to the removal of a large number of growth points and leaf areas, the total amount of photosynthetic products is reduced, the root system is inhibited and weakened, and the overall growth is reduced. Therefore, the degree of branch shrinkage and branch cutting of the whole tree or branch group depends on the age of the tree and the number of branches, so that it can be retracted year by year and updated alternately, so that the bearing branches are close to the trunk and the fruit is firm; The weak branches are rejuvenated, and the quality of flower buds and the number of fruits are improved. When shrinking and cutting every year, as long as the retraction degree is appropriate and the fruit is suitable, there is generally no phenomenon of excessive growth or weak growth.

(4) Long release is also called slow release or throwing release, that is, 1 ~ 2-year-old branches are not pruned. Long-term planting has the advantages of relaxing the top and increasing the number of short branches and foliage branches, which has a good effect on slowing down nutrient growth, increasing the accumulation of organic nutrients in branches and buds, promoting the formation of flower buds, increasing the number of normal flowers and promoting the early fruiting of young trees. Long-term release should be based on the tree potential and the strength of branches. For plants that grow too fast, let the whole tree out slowly. Because pomegranate branches grow vertically, in order to solve the problem of poor illumination after slow release, it is necessary to change the growth direction of long-release branches by combining measures such as opening the main branch angle, thinning the branches not too densely, and pulling down.

(5) Injury regulation: For leafy trees, the measures of girdling, girdling, carving and softening the branches are adopted to make wounds, so that the xylem and phloem of the branches are temporarily injured, and the effects of inhibiting over-nutrition growth, relaxing tree vigor and branch vitality, promoting flower bud formation and increasing yield are called injury regulation.

(1) girdling, girdling and carving. Cut the branches once or several times with a knife, and the incision should be deep into the xylem, so as not to hurt the xylem. Cut two circles with a knife and peel off the bark in the middle. This is called girdling. The width of the girdling opening is generally 65,438+0/65,438+02 ~ 65,438+0/8 of the diameter of the girdling. After girdling, the stripped bark should be turned over, then embedded in the original peeling place, and coated with drugs to prevent disease and bandage, so as not to fall off, which has the effect of protecting the wound in dry areas. Cutting is to cut the base of the ring branch longitudinally into the xylem with a knife. The length of the cut wound is 5 ~ 10 cm, and the distance between the cuts is 1 ~ 2 cm.

(2) twist the tip (branch) and take the branch (tip). Twisting branches means twisting flourishing branches downward or twisting the base, which not only sprains xylem and cortex, but also changes the direction of branches. Holding a branch is to touch the flourishing tip with your hand from the base to the top, hurting the xylem and making a sound without breaking it.

The time of injury varies with different purposes: before germination in spring, it can promote the transformation of leafy trees to reproductive growth and weaken vegetative growth; Delaying the growth of new shoots before flower bud differentiation can improve the flower bud differentiation rate; Before flowering, the fruit setting rate can be improved; Before the fast-growing period of fruit, it can promote the fruit to expand and mature early. Generally, the bigger the wound, the more obvious the wound effect, but the principle of the wound is not to weaken the branches too much, and the wound can heal in time.

(6) adjust the angle. For the big branches with small angle, vigorous growth and poor illumination, as well as the available flourishing branches and strong branches, the original growth direction of branches should be changed by supporting, pulling, bending and falling, so as to make the upright posture become oblique and horizontal, so as to alleviate the vegetative growth and the advantages of the top of branches, expand the crown, improve the illumination conditions in the crown, make full use of space and light energy, increase the accumulation of carbohydrates in branches and promote normal flowering.

(7) Bud-wiping, bud-wiping and sprouting-removing are all thinning branches in the growing season, mainly to remove useless sprouting branches on the trunk, cuttings on the main branches, saws and other parts, and dig out sprouting tillers in the rhizosphere of the trunk. Brushing buds to remove sprouting can change the light conditions in the crown, reduce the ineffective consumption of nutrients and water, and is beneficial to tree formation and promote flowering and fruiting. The best effect is to wipe buds in spring and summer, dig roots and tiller, and cut sprouting branches in summer and autumn.