Prevention of fruit cracking in growing litchi

The main results are as follows: 1. In the later stage of fruit development, root cutting and ring cutting are used to weaken the root activity, which has a good effect on reducing fruit cracking. However, the measures must be timely and appropriate, such as excessive control of root growth, which is disadvantageous to the normal development of fruit and the rapid recovery of tree potential after harvest.

2. in addition to balanced supply of nitrogen, phosphorus and potassium, trace elements such as calcium, boron, zinc and copper should also be supplemented in time, but excessive supply of nitrogen will lead to excessive vegetative growth of plants and increase the ability of root system to absorb fertilizer and water, resulting in excessive growth of pulp. 3. Using plant growth regulator 30 × 0.000001 naphthalene acetic acid to spray fruit ear at bud stage or after flowering, and before fruit coloring, such as extra-root topdressing, fungicide and bagging, etc., the anti-cracking effect will be better. Spraying the fruit with 10 × 0.000001 ethephon when the fruit is big and spraying it again every one month can reduce the fruit cracking. The use of 80 × 0.000001 ethylene at the initial stage of fruit cracking is beneficial to spraying the ear after drying in dew in the morning, which can enhance the elasticity of the pericarp, inhibit the rapid growth of the pulp, make the pericarp soft and reduce fruit cracking. Spraying 30 × 0.000001 cytokinin on the young fruit 15 days and 30-40 days after the female flower thank can promote the cell division and normal development of the pericarp and avoid fruit cracking. 4. The prevention and control of diseases and insect pests will increase the rate of fruit cracking, especially the peel infected by downy Phytophthora is often the breakthrough of peel cracking, which should be prevented as soon as possible and the cracked fruit should be removed in time.