High grafting and replacement method and Post-grafting Management of Chestnut

Chinese chestnut (scientific name: Castanea mollissima), also known as chestnut, Fagaceae, is native to China, distributed in Vietnam, Taiwan and Chinese mainland region, growing in the altitude of 370-2800 meters, mostly in mountains, has been widely cultivated. Chestnuts are rich in nutrients, and their vitamin C content is higher than that of tomatoes and ten times higher than that of apples. The minerals in chestnuts are also very comprehensive, including potassium, zinc, iron and so on. Although the content is not as high as hazelnut, it is still much higher than ordinary fruits such as apples, especially the potassium content is three times higher than that of apples.

I. Variety selection

A high-grafted tree can be a real tree or an original grafted tree. The main and secondary varieties in the same orchard should be matched reasonably, a high-yielding improved variety can be selected as the secondary variety, and the high grafting should be used as the pollination tree to improve the seed setting rate.

Second, the method of high connection and replacement

In the selection of scions, the first thing is to ensure the purity of varieties. Secondly, the branches with well-developed, full buds and disease-free insects should be selected on the trees with strong growth. Male flower segments without buds cannot be used as scions. The scions were collected during the dormant period of Chinese chestnut and properly stored in wet sand. Generally grafted in early spring, pay attention to scion and rootstock should be cut along with grafting, the section should be as deep as xylem, the scion should not be soaked after cutting, and the grafting action should be rapid.

Before high grafting, select 3-4 or even more than 10 evenly distributed main branches or secondary main branches to prepare for high grafting. The strength of the selected main branches or secondary main branches will be retracted, while a certain number of auxiliary branches will be retained. In principle, the number of auxiliary branches retained is more weak trees, less strong trees, more than 20-year-old trees or old trees retain 1 stick 3 of the whole tree, adult trees retain 1 stick 4, and less than 10-year-old trees or young trees retain 1 stick 6-1 stick 5 or not.

The high grafting position is high, and the growth is slow after that, but the fruit is early. Otherwise, the opposite is true. Therefore, it is appropriate to use high splicing and abdominal splicing. The strength of the selected main backbone branch was retracted and sawed off 10-30 cm above the branch point of the main branch and secondary main branch, and the cutting method was used at the sawing point. A few more buds are grafted in the middle and lower part of the branch by abdominal grafting.

III. Post-takeover management

The wound at the high joint should be disinfected and antiseptic, the large wound should be waxed or bandaged with plastic film, and the main branches and trunk should be whitened with lime water. Check the high grafted tree frequently. If the scion survives and sprouts, the sprouting on the rootstock should be wiped off at any time. When the new tip of the scion grows to 30 cm long, the coring is carried out to control the overgrowth and increase the number of branches. When the secondary branch grows to 30 cm long, coring is carried out to thicken the diameter of the grafted branch and enrich the lower branch bud. Using the pre-stored scion, after judging that the scion did not survive, cut the anvil below the original interface in time.