Causes and control measures of abnormal defoliation of citrus in winter

Citrus is one of the most common fruit trees in our life. It is an evergreen fruit tree with few leaves in autumn and wint

Causes and control measures of abnormal defoliation of citrus in winter

Citrus is one of the most common fruit trees in our life. It is an evergreen fruit tree with few leaves in autumn and winter. Once abnormal defoliation occurs, it will inevitably affect the yield and quality in the coming year. So what caused the abnormal defoliation of citrus in winter? Come and have a look with me.

1. Causes of abnormal defoliation of citrus in winter

1, nutritional deficiency

When citrus lacks trace elements such as nitrogen, phosphorus, potassium, calcium and boron in winter, it will cause leaves to turn yellow and fall off, which is one of the main reasons for citrus falling off.

2. Water imbalance

When the soil is too dry, the growth of plant roots is inhibited. When the evaporation of plants is greater than the absorption of roots, leaves will wither and curl, and petioles will fall off in severe cases. In addition, when water accumulates, the soil permeability is poor, which inhibits the root respiration. After a long time, the root system will rot, which will also cause the branches and leaves on the ground to turn yellow and fall leaves, and even cause plant death in serious cases.

3. Bad lighting

The growth and development of leaves are inseparable from photosynthesis. If the plants are closed and the light is insufficient, the leaves in the inner room will become bigger and thinner. The leaves are dim and even yellow. However, the weak light in winter will not be improved for a long time, which will cause a large number of fallen leaves in the branches of the inner room.

4. Keep hurting

During the growth period of citrus, red spider, scale insect, anthracnose and macular disease will all cause the greatest harm. If not prevented in time, a large number of leaves will fall in spring and winter.

5. Other reasons

In addition, phytotoxicity, fertilizer damage, strong wind, freezing damage and ring cutting may all cause abnormal defoliation of citrus.

Second, prevention and control measures

1, strong tree potential

In production, phosphorus, potassium fertilizer and organic fertilizer should be applied in combination with deep ploughing to make the root system take root deeply, and foliar fertilizer should be sprayed at the same time, reasonable pruning and timely irrigation and drainage should be carried out to cultivate vigorous tree vigor and improve the antibody of trees. For plants suffering from phytotoxicity, foliar fertilizer and brassin can be sprayed on the branches and leaves of the crown to reduce defoliation caused by improper girdling. For defoliation caused by improper girdling, foliar fertilizer should be sprayed in time or the girdling mouth should be bonded with electric tape, and at the same time, pesticides such as sulfur mixture which is easy to defoliate should be avoided within one month after girdling.

2, do a good job of pest control.

Before overwintering, it is necessary to do a comprehensive garden cleaning work to reduce the base of pests and diseases. Adding 2,4-D to garden cleaning is beneficial to antifreeze and leaf protection. For a large number of fallen leaves caused by anthracnose and macular disease, once found, it is necessary to prevent and control them in time to reduce the harm, and spray them in time during the growing season to protect the leaves.

3, pay attention to antifreeze

In addition to planting in the right place, applying sufficient base fertilizer and painting the trunk white, we should also pay attention to spraying fallen leaves after citrus is picked in winter and before freezing. The second is to take emergency anti-freezing measures, spray potassium dihydrogen phosphate solution in time before frost to slow down the thawing of trees and restore the function of leaves.

Step 4 supplement nutrition

Attention should be paid to element deficiency in production, and once it is found, it should be prevented in time, so as to suit the remedy to the case and apply whatever fertilizer is lacking.

The above is an introduction to the causes and preventive measures of abnormal defoliation of citrus in winter. I hope I can help you. If you want to know more, please pay attention to us.

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