(1) Main branches and auxiliary branches form permanent branches of the crown skeleton and tree shape in the overall structure of the crown, which are called main branches, such as main branches, main branches and side branches. Temporary vegetative branches and various branches are collectively referred to as auxiliary branches or non-main branches. The main function of backbone branches is to form the skeleton of trees and bear branches; The main function of auxiliary branches is to form a crown and assist trees to grow and bear fruit.
Backbone branches at all levels act as permanent branches. Therefore, it is required that the distribution in the crown is uniform and reasonable, the subordinate relationship is clear, the structure is firm, the opening angle is appropriate, the growth is balanced, and the ventilation and light transmission are good, which is conducive to high quality and high yield and prolonging the fruiting period.
(2) When annual branches with leaves are produced in that year, new shoots, annual branches, biennial branches and perennial branches are called new shoots. Due to the different seasons of new shoots, they can be divided into spring shoots and autumn shoots. Spring buds are spring buds and autumn buds are autumn buds. The spring shoot tissue is rich and robust, which is beneficial to flower bearing and flower bud differentiation in the next year. Autumn shoots have poor tissue, poor cold resistance and weak flower-forming ability, but in some years and varieties, autumn shoots may also form flower buds. Therefore, technical measures are taken to promote spring shoots and control autumn shoots in production. When pruning, in order to inhibit the vigorous growth of trees and promote them to grow short branches, pruning is often carried out at the bud at the junction of spring shoots and autumn shoots, that is, "capping" pruning.
In deciduous fruit trees, the new shoots that sprouted that year are called 1 annual branches, that is, the new shoots before defoliation. Branches that grow for 2 years from germination to the second spring are called 2-year branches, and so on.
(3) A vegetative branch is a branch that only leaves but does not bear fruit in that year, which is called a vegetative branch, also called a growth branch or a development branch. Because of its different growth and development, it can be divided into long branches, leafy branches, thin branches and normal branches.
Most of the long branches are germinated by the stimulated hidden buds. This kind of branches grow vigorously, erect, fast, lack of tissue, large and thin leaves, long internodes and thin branches. The excessive growth of branches on young trees or trees at the initial fruit stage consumes a lot of nutrients, destroys the balance of tree potential and disturbs the tree shape, which is of no use value and should be drained as soon as possible; If there is space, it can also be controlled and used; Excessive growth of branches on aging trees can be controlled, utilized or thinned according to the planting location, space and other factors. Those with useful value should be picked as soon as possible to promote their growth, which can be used to update the crown or cultivate into fruiting branches. Those that are of no use value should be removed as soon as possible.
Thin and weak branches are mostly germinated by weak buds in inappropriate positions. The branches are slender, the leaves are small and thin, the buds are pointed and flat, the tissues are not full, the renewal ability is poor, the growth is weak, and it is difficult to become flowers. Except for a few that can be kept and used, the surplus should be thinned out as soon as possible.
The length of leaves and branches is mostly below 1 cm, the internodes are extremely short, and there are many rosettes. Generally, there are 4 ~ 9 leaves, which stop growing early and accumulate more nutrients, and are most likely to form flower buds. Care should be taken when pruning.
(4) fruiting branches (Figure 2) Branches with flower buds that can directly blossom and bear fruit are called fruiting branches. Some fruit trees, such as grapes, dates, chestnuts, persimmons, etc. , which can blossom and bear fruit on the new shoots of that year, is called 1 year fruiting branch; However, some fruit trees, such as apples, pears, peaches, plums, apricots and so on. A flower bud is formed on a branch that is born in the first year and blooms and bears fruit in the second year, which is called a two-year bearing branch.
According to the different types of fruit branches, they can be divided into long fruit branches, middle fruit branches, short fruit branches, short fruit branches and bouqueted fruit branches.
Fig. 2 Types of fruiting branches
1. Long fruit branch 2. Middle fruit branch 3. Short fruit branch 4. Short fruit branches.
Long branches on apple, pear and other fruit trees, which are more than 15 cm in length and have terminal buds; The long fruit branches of peach, plum, apricot and other fruit trees are more than 28 cm long, and more than half of the lateral buds are flower buds, especially the peach varieties in Central China, which have long fruit branches and should be protected and utilized when pruning.
The mesocarp length varies with tree species and varieties: the mesocarp length of apple, pear and other fruit trees is 6 ~15 cm; The middle branch length of peach and apricot trees is 1 1 ~ 25 cm.
The length of short branches of apple, pear and other fruit trees is below 5 cm; The length of short branches of plum, apricot and other fruit trees is below 10 cm. The older a fruit tree is, the shorter its branches are. Young apple trees and early fruit trees mainly bear long and medium fruit branches, while trees with full fruits and weak growth mainly bear short fruit branches. When pruning, attention should be paid to cultivation, protection and utilization according to different tree species and tree ages.
The short fruit branch group is a group of short fruit branches formed by continuous branches after the short fruit branches bear fruit, and it is also a unique fruit branch of apples and pears. The fruiting ability of short fruit branches is generally 4 ~ 7 years. When pruning, we should pay attention to renewal and rejuvenation to prolong the life of fruit.
Bouquet-shaped fruiting branch The length of this fruiting branch is only 1 ~ 2 cm. The terminal buds are mostly leaf buds, and there are dense flower buds on the branches, which look like bouquets when they bloom. They are unique fruiting branches of stone fruit trees such as peaches, plums, apricots and cherries. This kind of fruit branch increases with the increase of tree age and the weakening of tree potential, and the continuous fruiting period is only 1 ~ 2 years.
Axillary flower buds Some apple varieties, such as Fuji and Jinai, and pear varieties, such as Fengshui, are easy to form axillary flower buds. For example, young trees or trees with few flowers should be protected and utilized when pruning. But the results are generally not great.