Suction bud can be used to propagate seedlings, and it is also the follow-up mother plant, which bears fruit in the following year. When it is used as a successor plant, the quantity, morning and evening and location of its occurrence directly affect the fruit yield and quality in the next year. The strong mother plant absorbs buds early, more and lower, which is beneficial to the next year's fruit. If the mother plant absorbs many buds, except the seedlings, 1 ~ 2 plants with low growth position are generally selected for the next year's results, and the rest are removed early to avoid consuming nutrients.
Using sucking buds as seedlings will bear fruit early after planting, but because the size and strength of sucking buds are very different, it is necessary to choose planting according to classification to achieve consistent fruit maturity. There are few sucking buds of Kane species, so the fully mature sucking buds with hardened leaves, open leaves, 25 ~ 30 cm long buds and brown small roots under the basic leaves should be selected as seedlings.
Phylogenesis
The evolutionary history of biological races. Fruit trees mainly refer to the history of the emergence and development of a certain family, genus and species.
The different stages and ages of individual development of fruit trees reflect the development process of this fruit tree system in different degrees in morphological characteristics. For example, the seedlings of cultivated types are characterized by small leaves, many needles and many branches, which are easy to take root, reflecting the characteristics of primitive wild fruit trees in the early stage of system development; With the development of individual development in the middle stage, it shows the characteristics of large leaves, large buds and gradually disappearing needles in the adult fruit-bearing stage, and the characteristics of cultivated fruit trees appear. These characteristics reflect the advanced stage of system development. For decades, the imprint of this phylogeny can still be clearly observed in trees.
Phylogenetic development is also reflected in physiology. The senescence of adult fruit trees growing from seedlings always starts from the higher secondary branches at the top of the crown and gradually moves to the lower secondary branches, which reflects that the higher secondary branches are old in phylogeny. On the contrary, the germination of fruit trees always comes from the lower-level backbone branches, which reflects that the younger the lower-level backbone branches are, the stronger their vitality is.
The evolution of organisms is completed by two closely related development processes: individual development and systematic development. In the development of biological system, three factors play a major role, namely heredity, variation and selection. ① Inheritance is the basis of biological evolution. Genetic performance is the similarity between the previous generation and the next generation, that is, the offspring produce individuals similar to their parents in the same way and manner as their parents. Because of the potential ability of heredity, the stability and continuity of species are guaranteed, and biological races can multiply and develop. ② Organisms are variable. So that organisms have the possibility of survival and development, and can better adapt to the changed external living conditions, and the variation of biological genetic material can pass this variation on, providing raw materials for biological evolution and ensuring the evolution and development of organisms. ③ Selection determines the direction of biological evolution. Inheritance and variation are two factors in biological evolution, and selection determines the development direction of biological variation and inheritance. Due to the leading role of selection, the so-called "directed evolution" appeared in the development of biological systems. Selection is divided into manual selection and natural selection. Through artificial selection, the organisms that are beneficial to human beings are preserved and the individuals that are unfavorable to human beings are eliminated; Natural selection is the selection of organisms within its scope by external environmental conditions, that is, organisms suitable for this condition are retained, while those unsuitable for this condition are gradually eliminated. Both artificial selection and natural selection are of great significance to biological evolution. All fruit tree varieties used in production are cultivated by the interaction of artificial selection and natural selection from wild fruit trees.
summer pruning
Pruning refers to the pruning of fruit trees from germination to defoliation, also known as growth pruning. It mainly includes measures such as delaying pruning, re-cutting before flowering, removing buds, removing cores, thinning branches, twisting tips, smoothing branches and supporting. Summer pruning is generally not enough to assist winter pruning, but on fruit trees such as grapes, apricots and citrus, as well as young and prosperous trees such as apples, pears and peaches, summer pruning can more effectively adjust the intensity of vegetative growth, balance the tree vigor, or rapidly expand the crown, promote flowering and fruiting, and improve the quality.
Pruning principle
Summer pruning is carried out in the growing season of fruit trees and the period of relatively vigorous life, which is sensitive and direct to summer pruning. Therefore, summer pruning should also consider the biological characteristics of fruit trees, and choose different measures and suitable periods according to the purpose and requirements of summer pruning. In summer, the vegetative growth and flower bud formation potential of different fruit trees, the precocity and heterogeneity of buds are mainly utilized. Therefore, it is generally limited to plants with sufficient light and heat resources, good fertilization conditions and vigorous fruit tree growth to give full play to the summer effect.
Pruning action
Summer pruning not only has the function of general winter pruning, but also has some special physiological functions: (1) For fruit trees with large growth and many branches in summer, we can make full use of their growth, carry out summer pruning, realize garden shaping or accelerate the formation of young trees. (2) Cutting branches with leaves can obviously weaken the top advantage, promote the germination of lower buds, and make the tree look relaxed and compact. (3) According to the nutrient level and flower amount of the tree, thinning dense branches, redundant branches and excessive flower branches before and after flowering can adjust the relationship between growth and fruiting and effectively overcome the big and small years. (4) After the growth of spring shoots stops, thinning the dense and vigorous branches at the periphery or between layers according to the degree of canopy closure can improve the illumination in the inner room and cultivate the stereoscopic effect; ⑤ Pruning after harvesting can delay the flowering in the second year and reduce the male flowers; Retraction and pruning of early-maturing peaches after harvesting can control the crown, force the secondary branches to become flowers, and realize close planting and stable production; Pruning grapes in summer can prevent excessive growth, promote fruit setting, and force winter buds to germinate for the second time (see grapes).
Summer cuttage
According to the cutting method can be divided into:
Delayed pruning
Postpone winter pruning until the fruit trees germinate. When the fruit tree germinates, the storage nutrition of the tree body is transferred to the top of growth, and cytokinin and auxin are also concentrated at the top, which promotes the lateral bud germination and controls the tree potential. It is mostly used for young trees, and the effect is more obvious for Guoguang apples with low branching rate and germination rate. The time to postpone pruning depends on the potential of the tree. Too strong trees and growing branches can even be pruned after the growth begins.
Pruning before flowering
Refers to the adjustment of flower branches and leaf branches when winter buds can accurately identify flowers and leaves after germination. Some apple varieties are difficult to identify flower buds when they are cut in winter. In the years with few flowers, if it is pruned normally, sometimes some buds will be cut off, resulting in few flowers and affecting the yield. Therefore, when pruning in winter, consciously reduce the thinning times of short and medium branches. When the flower buds can be clearly distinguished, all the flower buds are reserved, and the unfruitful branches are adjusted according to the pruning requirements. Cutting before flowering is also to cut off excessive flowers after germination, and adjusting the proportion of leaves and fruits can avoid the occurrence of big and small years. The number of female flowers can be increased by removing the tail branches after germination or when the mixed buds are red (see chestnut). In areas where the freezing injury of flower buds is serious in winter, more flower buds should be reserved during cutting in winter, and then re-cutting should be carried out according to the freezing injury of flower buds during germination.
Wipe and remove buds
In early spring, at the beginning of growth, the buds without long branches are erased in the bud stage in advance; Adventitious buds often germinate in the crown cavity, especially around the big branch scissors and incisions, and should also be cut off at the initial stage of germination. For grape, citrus and other fruit trees with many sprouting branches and vigorous growth, bud wiping and shoot cutting (see bud wiping and shoot cutting control) can save nutrients and improve the lighting conditions in the crown.
Pick a heart
Remove the top of the lush new bud. After enucleation, it can inhibit its growth in a certain period of time, reduce nutrient consumption, improve the photosynthetic capacity of leaves below enucleation, enrich buds, and improve the flowering rate or fruit setting rate of other parts. Picking can be divided into three periods: at flowering stage and after flowering, picking the branches on the fruit table or near the flowers and fruits can improve the fruit setting rate and have better effects on grapes, apples and pears; During the rapid growth period in summer, denucleation of vigorous main branches, leading branches or long branches at the gap of tree crown can promote branching, open the branching angle, accelerate the formation of tree crown, or supplement space (see plastic surgery in the garden); In autumn, gently pinching the middle and long branches of Wangzhuang tree that have stopped growing can make its lateral buds germinate or sprout short branches to form some flower buds, so that the lateral buds are full and the branches are full (see flower promotion technology).
Torsional tip
Mostly before the middle and long branches stop growing or before the flower buds form. For the vigorous middle branch or fruiting branch, twist the upper part of the branch to make it hurt, so as to slow down the growth and promote the formation of flower buds.
Smooth branch
It is divided into spring and autumn. Spring is in the middle and late May, and autumn only grows in autumn. Hold the middle and lower part of the upright or obliquely growing branch with one hand, and hold the upper part of the branch with the other hand. Hold the thumb against the branch, bend down slowly and move forward continuously, and repeat from the base if necessary (see figure). It is also called taking branches to destroy the wood of branches without cracking the cortex. After pruning, the branches become horizontal or drooping, coupled with wood damage, the growth slows down and it is easy to form flower buds. Strolling through branches can also change the angle and orientation of branches, transform and utilize abandoned branches, and form backbone branches or branches. Apples, hawthorn, pears, chestnuts, etc. Can be applied.
Pull branches
Generally, it should be carried out in the rapid growth period of branches in spring. For the main branches and side branches with vertical or small angles, use ropes and aluminum wires to spread them to a certain angle and direction, adjust the tree shape or improve the germination rate and flowering rate. Many fruit trees, such as young apples, pears, hawthorn, peaches, plums, apricots, chestnuts and oranges, can be reshaped faster and bear fruit earlier by pulling branches. If the branches are pulled by wire, thick paper, rubber or old soles should be padded to prevent the wire from being embedded in the branches. The function of supporting branches is similar to pulling branches. China is often supported by wooden sticks. Wood strips about 3 cm square are commonly used abroad, with nails at both ends, which are relatively stable after support.
In addition, in the growth period of new shoots in spring, or when the leaves of new shoots are dense in early summer, redundant and dense new shoots are removed from the base to improve the illumination in the inner room; Cutting off 1/3 ~ 2/3 new shoots in early autumn or late growth period can also improve the light conditions, promote the transformation of cut buds into flower buds, or promote the fullness of axillary buds (see pruning); For another example, when the growth of jujube head begins to slow down, thinning the over-dense new jujube head, removing the core or smearing the bud can also improve the growth of new jujube head and cultivate good fruiting branches.
It is more accurate to judge the tree structure and branch density of fruit trees before defoliation Therefore, the adjustment of the age structure of mature trees can be carried out in autumn. After thinning the big branches in autumn, the wound can be healed before winter, which can reduce the disease or freezing injury, and at the same time, it can also reduce the stimulation to the dark buds of the cut branches and prevent the branches from sprouting in the next spring.
Pruning in summer has a great influence on tree vigor, because it cuts off new branches with leaves and reduces the nutritional area. Therefore, we should give priority to light pruning and sparse, with fewer wounds to prevent excessive pruning.
Summer shoot
See the vegetative branches.