What Is The Cause Of Freezing Damage To Kiwifruit? What Should I Do?

Kiwifruit is widely planted in our country, and the planting area is constantly expanding. With the advent of winter, antifreeze management of kiwifruit is very important, so what is the cause of freezing damage in kiwifruit? How to prevent kiwi fruit freezing damage? Let's take a look!

   1. The cause of occurrence

   Before the deep winter, the temperature is still relatively high, and then as time goes by, the temperature will drop sharply. If the work of overwintering is not done well, the kiwi tree will not be able to adapt to the changes in temperature, especially the cold resistance of the mother branch is very weak. And in the early spring, the temperature has not yet risen, but the vines of the tree have begun to germinate. The temperature does not reach the appropriate range, resulting in the freezing of the branches and the decline of cell viability, which affects the cells, causing damage to the branches of the tree and causing freezing damage to the kiwifruit.

   2. Symptoms

   After the kiwi fruit tree suffers from freezing damage, the surface of the fruit branches will shrink and the color will gradually become darker, especially the color in the cortex. In severe cases, cracks will appear on the surface of the branches, the xylem is dark in color, the growth rate is significantly reduced, and the germination ability of the branches is weakened. The growth of new shoots will also be greatly affected, and new shoots will not even germinate. Fruit trees that produce freezing damage will have a sharp increase in mortality, reduce tree vigor, produce various wounds, and cause various diseases and insect pests.

   3. The law of occurrence

   The law of occurrence of kiwi disease will vary according to the planting area, topography and the location of the fruit tree. Among them, the incidence of disease is more serious in areas with large temperature fluctuations between day and night, and the ventilated areas are more severe than the leeward areas. The main occurrence pattern is still reflected in the fruit branches. For example, the old branches have strong cold resistance, and the new branches are prone to freeze damage. The strong-growing branches are lighter than the weak-growing branches, etc., so everyone should follow these aspects when doing winter work.

   4. Preventive measures

   First of all, we must do a good job in cultivating and weeding, increase the application rate of organic fertilizer, and improve the cold resistance of kiwi trees for the purpose of cultivating roots and tree vigor. Do not leave too much fruit, clean up the garden after harvest, strengthen fertilizer and water management, and control the proportion of organic fertilizer when fertilizing. After the fall, reduce the application of nitrogen fertilizer, increase phosphorus and potassium, and promote the growth of branch tips. Then build a windbreak belt to cultivate soil in time to enhance the orchard’s thermal insulation capacity, prevent cold winds, and reduce the incidence of frost damage.