In the process of pear planting, it is easy to suffer from freezing injury. What effect will it have?

For example, the freezing injury in early spring usually damages the flower buds of pear trees, and even causes the flower buds to turn brown at the base, thus reducing the quality of the flower buds of pear trees. If it is heavy, it will cause the bud base to turn brown and then die slowly. Worse, the whole bud will die, which will seriously affect the normal germination, flowering and fruit setting of pear trees. In addition, freezing injury in early spring will also cause harm to pears. When the freezing injury is mild, the style will turn brown, which will affect the normal pollination and fruit setting. When the freezing injury is serious, the whole flower organ will turn brown and die, losing its normal function. Freezing injury in early spring has a far-reaching impact on young fruits of pear trees, especially the calyx end of young fruits. When illuminated, brown stripes will appear at the end of calyx, which will affect the quality of fruit. In severe cases, the small fruit will turn yellow and fall early.

Frost damage mainly harms young branches of pear trees, which is less harmful than the other two kinds of frost damage, but it is very harmful to the trunk of young trees and often causes young trees to die. Generally, the cambium of branchlets becomes brown necrosis after being damaged, resulting in weak growth of branches; Heavy will cause the death of the whole branch, seriously affecting the tree potential. Frost damage in late winter mainly harms the main branches and trunk of pear trees. When the branches are damaged, the bark surface tissue will turn brown, and the cortex at the base of the trunk will burst, which is easy to induce rot, resulting in slow growth, weakness and low yield of the branches. In severe cases, the inner and outer tissues of bark tissue will turn brown and die, leading to the death of branches, which in turn leads to the death of the whole pear tree. Measures to avoid freezing injury of pear trees. Strengthen the cultivation and management of pear trees and enhance the tree potential.

Farm manure and other organic fertilizers can enhance the tree vigor, scientifically control the number of fruits, and pay attention to the prevention and control of pests and diseases. All cultivation management is based on strengthening tree potential, which will naturally improve the frost resistance of trees. This is very effective for preventing and controlling freezing injury. In addition, the water in early spring. Take anti-freezing measures in the season when the temperature drops, fruit farmers should always pay attention to the weather forecast, especially when there is a cold current, and take anti-freezing measures for orchards and fruit trees, such as putting smoke in orchards and spraying water on trees. For areas prone to freezing injury in late winter (such as pear tree cultivation areas in the north), after winter, trees can be covered with cold-proof objects or the whole orchard can be covered with cold-proof objects to avoid freezing injury caused by low temperature in late winter. The degree of freezing damage of branches varies with the age of branches, and the order of freezing damage is 1 annual branches, 2-year branches and perennial branches. The occurrence of freezing injury is related to the development degree of branches.

Due to insufficient organization and underdeveloped protection organization, it is easy to freeze to death; Although the normally developed branches have stronger cold resistance than the tender buds, freezing injury can also occur when the temperature is too low. Only the pulp becomes discolored in mild freezing, and the phloem and cambium are damaged in severe freezing. Some branches have the same appearance, but they germinate late, their leaves are thin or deformed, and their growth is abnormal. After the xylem is cut, it turns brown and then forms a black heart. If it is serious, the whole branch will dry up. The characteristics of trunk freeze injury are trunk fracture, frozen cortex sinking or cracking, and internal browning tissue necrosis. In severe cases, all cortex and cambium at the base of the tissue are frozen to death, leading to tree decay or whole plant death. Root neck freezing injury Root neck freezing injury is caused by the drastic change of microclimate near the ground. After the root neck was frozen, the cortex changed color and died, which occurred locally, forming a black circle and the whole plant died. Root neck freezing injury is very harmful to fruit trees, which often causes tree weakness, disease or whole plant death.