Tree structure and shaping method of two branches and one stem in apple dwarfing and dense planting

Tree structure and shaping method of two branches and one stem in apple dwarfing and dense planting

1 structure of two branches and one stem in dwarfing cultivation of apple

The dry height is 80 °120 cm above the ground, and two main branches extending between rows are cultivated. The horizontal angle of the two main branches is 180 °, the base angle between the main branch and the middle stem is 70 °~ 80 °, the waist angle is 60 °~ 70 °, and the tip angle is 50 °~ 60 °. The long-axis fruiting branches with different dispersing and drooping types were directly cultured on the two main branches. A total of 20 to 30 small and medium-sized fruiting branches with an angle of more than 90 °and less than 130 °were cultivated on the central leadership. The height of the tree is 3 meters. The crown is flat and conical. The branch-stem ratio of the main branch to the central stem was 1 ∶ 2: 3, and the branch-stem ratio of the central trunk and the main branch to the branch group was 1 ∶ 3 / 5.

2 the method of tree shaping and pruning with two branches and one trunk

2.1 determination of row spacing

Apple trees can be planted with a plant spacing of 1.5 to 2 meters and a row spacing of 5 to 5.5 meters, that is, wide rows and close planting, with a planting number of 61 to 90 plants per mu. This is the basis of two-branch and one-stem shaping.

2.2 fixed drying

Three-year-old seedlings were selected and dried between 1m and 1.3m, and the fourth and fifth buds were selected in the interrow direction to erase the second and third buds.

2.3 first year pruning

Wipe off the sprouts below 80 cm in time, and when the oblique branches on the middle stem grow to 30 cm, two robust branches facing the interrow are selected as permanent main branches. The two main branches and the central stem are not treated by taking or turning branches, and the over-strong competitive branches and other oblique branches are all sagging from the base to control the growth and strengthen the middle stem.

In winter pruning, only the middle stem and the two main branches extending between the rows were left, and all the other branches were removed from the roots. The extended branches of the middle stem were cut off at the semi-full buds of autumn shoots, and the second to third buds were erased to promote the thickening of the middle stem and inhibit the growth of competitive branches. For the weak ones less than 50 cm in length, the two main branches can be cut at the semi-full buds at the tip, erase the 2nd ~ 3rd buds, restrain the competitive branches and promote the growth of the main branches. if the small main branch is more than 50 cm, it will not be cut and a tree-shaped skeleton will be formed in the same year.

2.4 2nd year pruning

(1) Bud carving: from late March to mid-April, the buds on the middle stem are carved first, then the buds on 2 main branches are carved every 10 days or so, and the buds on the middle trunk are carved from less than 20 cm under the cut to more than 10 cm away from the upper main branch, and a bud is carved every other bud; the two main branches are left 20 cm at the base and 20 cm at the tip, and are carved with a steel saw blade 0.5 cm above the buds on both sides of the branch.

(2) sprouting: timely erase the sprouts on the back of the main branch and the sprout on the trunk.

(3) brace: when the branch on the middle trunk grows to 20-25 cm, it is supported with a toothpick to open the base angle.

(4) take branches or turn branches: in May, August, take branches or turn branches on the middle stem and the main branch, lateral shoots to open the angle and ease the growth potential.

(5) thinning: competitive and erect branches with a stem ratio of more than 1 / 2 on the middle stem and the main branch will be thinned after late August.

(6) drawing branches: for two main branches, the branches can be pulled when the length is about 1 meter, so that the base angle is 80 °~ 90 °and the waist angle is 60 °~ 70 °. Starting from September, the lateral branches of more than two main branches of the middle trunk should be pulled to 95 °~ 130 °and droop naturally, not into an arch.

(7) Winter pruning: remove the lateral branches and untreated competitive branches and overgrown branches on the upper trunk and the main branch, and remove the branches below the two main branches, and all the branches will be laid slowly without cutting.

2.5 3rd year pruning

(1) Bud carving: buds are carved on the annual branches of the middle stem and the two main branches and on the missing branches of the biennial branches. The method of sprouting is the same as in the second year.

(2) sprouting: erase the buds on the back of the main branch.

(3) support: when the branches of the same year on the middle trunk grow to 20-25 cm, the base angle is 90 °.

(4) taking branches or turning branches: the position and method are the same as those in the second year.

(5) Ring cutting: for Fuji varieties which are difficult to form flowers from late May to early June, they can be cut in the middle stem or at the base of the main branch to control the growth of new shoots, promote capping and easily form flowers.

(6) the methods of branch drawing and winter pruning are the same as the previous year.

2.6 pruning and culture and renewal of fruiting branches in the 4th year and beyond

(1) the main branch is permanent and does not need to be renewed, and 1.5 meters of work lane should be left between the rows. When the main branch reaches the required length, and after a large number of fruits, it can leave 3-5 cm shrunken buds at the base of the main branch. If the base angle, waist angle and tip angle are not in place, they should be pulled in place in time. When the central stem reaches the desired height and a large number of fruit is hung, the weak branch is used to change the head.

(2) Culture and renewal of fruiting branch group. The small and medium-sized fruiting branch groups were cultured directly on the middle trunk, but the small and medium-sized branches on the middle trunk could not be pressed on the lower main branch, otherwise the growth and fruit of the main branch would be affected; the loose long-axis fruiting branch group cultivated on the two main branches was reasonable, and the oblique, horizontal and drooping branch groups were scattered and orderly. The branch group released slowly and did not cut for years, and then retracted after 3-5 years, when the secondary shoot of Guotai was weak. If there is a new branch group nearby, the weak branch group can be thinned and replaced by the new branch group.

3 technical effect

3.1 convenient for mechanical operation, high yield and good benefit this tree shape realizes wide row and dense planting with the same number of plants per unit area as the non-main branch tree with main branches.

The row spacing is more than 2.5 to 3 times of the plant spacing, which is convenient for mechanized operation and labor-saving cultivation, reduces the labor cost, and has higher yield and better benefit than other trees with main branches in the first 10 years.

3.2 facilitate management and improve labor efficiency

The tree shape reduces the height of the tree, raises the trunk, facilitates management and fruit, and improves the economic benefits of the orchard. This also improves the ventilation and light transmission environment at the base of the crown, which is beneficial to the cultivation of long-axis fruiting branches, simple pruning and improving labor efficiency.

3.3 Saving production costs and reducing production input

The tree shape does not need frame wood input, which saves the production cost and promotes the further popularization of dwarfing and dense planting technology. Because there are two main branches extending between the rows, like the two wings of the plane and the wings of the bird, they play the role of balancing the tree body, making the middle stem upright without frame input, and only this item saves 800 to 1,500 yuan per mu or more. At present, the biggest bottleneck restricting the development of dwarf rootstock fruit trees is the input of seedlings and timber. The research of this technology can greatly accelerate the popularization of dwarf rootstock orchard cultivation technology.

3.4 robust trees are conducive to early flowering and early fruiting.

The tree-shaped directional culture of the main branches, so that all the main branches extend to the rows, the garden appearance is neat, the branches do not intersect each other, and the two main branches are symmetrically balanced and there is no crown deviation. Because there are two large main branches, the power is scattered, the tree body is robust, there are few branches, and it is easy to form horizontal, oblique and drooping fruiting branches, with a large number of branches per mu, more medium and short branches, easy to flower and bear fruit early. [Jishan Huayao]

3.5 overcome the phenomenon of "neck jam" with good ventilation and light transmission

The invention overcomes the phenomenon of "neck jam" with main branches, such as small crown sparse layer shape, free spinning shape, improved spinning shape and so on, and the shortcomings of a small number of trees per mu. Because there are only two main branches, there are 1 to 3 less main branches than other tree-shaped bases with main branches, so the distance between plants can be narrowed, the phenomenon of "neck jam" will not occur, and the upper and lower trees can be balanced. Moreover, it has no side branches, good ventilation and light transmission, reasonable structure, simple tree shape and convenient management.

3.6 simplified pruning technology, easy to popularize and apply

The tree shape perfectly combines the advantages of cultivating small fruiting branches on the upper part of the tree-shaped central trunk, such as fine spinning, high spinning and trunk, with the advantages of cultivating loose long-axis fruiting branches on the small crown happy-shaped main branch. it not only increases the growing position and the number of branch groups, but also simplifies the pruning technique, and the method is easy to master and easy to popularize and apply.