According to the position of inflorescence, the choice of pruning method is closely related to variety characteristics, site ecological conditions, tree age, shaping method, branch development and bud fullness. Generally speaking, wine grapes can be pruned with short branches, but different varieties of table grapes are different: the varieties with inflorescence at 1 ~ 3 nodes and branching rate above 70% use short branches for pruning, such as Zuijinxiang; For varieties with more than 4 inflorescences and about 50% fruiting branches, trim the middle branches and the short branches of vegetative branches in the following year, such as seedless white chicken heart; For varieties with uncertain inflorescence position, medium and long shoots should be pruned, such as Meirenzhi. European and American hybrid grapes are not strict about the thickness of the cut, and the thickness of the cut of Eurasian grapes is 0.8 cm ~ 1.0 cm.
(2) Thinning The pruning method of pruning the whole vine (including 1 annual and perennial vines) from the base is called Thinning. Densification of branches is beneficial to improve the distribution of light and nutrients; Sparse the old and weak branches and leave new and strong branches to maintain the growth advantage; Sparing too many branches and leaving moderate branches can balance the tree potential; Sparse branches of pests and diseases to prevent the harm and spread of pests and diseases.
(3) Shrinking and cutting off a section of vines more than 2 years old is called shrinking and cutting. Its main functions are: updating the trend, cutting off the old branches of the previous section, leaving new branches, making them in a disadvantaged position; Prevent the expansion and outward migration of the result website; It has the functions of thinning branches and improving illumination, such as shrinking big branches and balancing tree potential.
(4) Regeneration of branches ① Regeneration of bearing mother branches.
Regeneration of two branches: when pruning in winter, leave two fully mature 1 annual branches near the old vines on each fruiting mother branch, with the upper 1 as the second-year fruiting mother branch and the lower 1 as the spare branch. When cutting in the winter of the following year, the upper bearing branch is thinned, and two branches near the base are selected from the branches sprouting from the lower preparatory branch, wherein the upper branch is used as the bearing mother branch of the next 1 year, and the lower branch is used as the short-cut preparatory branch, which is pruned every year.
Single branch regeneration: a method of simultaneously bearing fruit and cultivating preparatory branches on the same bearing mother branch. Pruning in winter leaves 2 ~ 4 bud eyes as fruiting mother branches. After germination in the second year, new branches with base 1 bud eyes are taken from inflorescences as preparatory branches for culture. When cutting in the winter of the following year, the upper branches are removed, and 2 ~ 4 buds are cut from the branches prepared at the base as the fruiting mother branches in the following year, and so on every year.
② Regeneration of perennial branches and vines.
After pruning every year, papules and scars on perennial vines increase, which affects the smooth flow of dredging tissues; In addition, for lightly cut vineyards, the lower part is exposed, and the produced part moves outward, which leads to the thinning of new shoots, the reduction of fruit ears and grains, and the decline of yield and quality. In this case, some large main vines or lateral branches need to be updated. Anything that removes the main vine from the foundation is called a big update. Before the big renewal, we must actively cultivate the tillers sprouting from the surface or the new branches growing from the base of the main vine, so it is called new vine. When the new vines are enough to replace the old vines, the old vines can be removed.
Generally, one-arm and one-arm trees do not need to be greatly updated, but the perennial fruiting mother branches should be updated in time, and the new shoots germinated by hidden buds should be selected as preparatory branches at the transverse arm and base of the branch group for culture; If there are no new buds, the branches and vines can be taken back according to the spatial position to promote the latent buds to germinate new buds. After the new buds meet the renewal requirements, the old branches and vines can be cut off.