Fruit Frost Damage Management and Remedial Measures
In the winter, when temperatures drop to zero, some orchards that are cultivated or managed improperly are often susceptible to low temperatures, resulting in frost damage to fruit trees. After freezing damage to the fruit trees, the blockage of the resinous substances, root absorption and transportation, leaf transpiration, photosynthesis and growth of plants are all destroyed. Therefore, the management system should restore the transmission system as soon as possible to heal wounds and promote dormant buds. Germination, restore normal growth. I. Symptoms of frost damage in fruit trees 1. Frozen root damage: Roots grow underground, freezing damage is not easy to find, but the effect on the above-ground part is very significant. It shows that the buds are late or irregular in the spring, and some are lightly affected by freezing. Although they can sprout, they grow slowly. The new shoots that have been taken out seriously are withered and dry. After rooting, it was found that the outer skin became brown, and the cortex was separated from the wood and even fell off. 2. Freezing damage to roots and stems: Freezing damage to roots and stems is caused by severe changes in the microclimate near the ground. The absolute minimum temperature is lower than the temperature and the temperature difference is large. Especially in the case of water accumulation in the roots and greediness, the frost damage of roots and stems occurs more easily. Sometimes it freezes on the side of the rhizome and turns brown in the ring to die. 3. Frozen stem damage: The main trunk is broken and the branches are frozen. The skin layers of the frozen branches become subsidence or cracking. The internal browning tissue is necrotic. In severe cases, the cortex and formation layers of the tissue base are all frozen to death, and the affected branches wither, causing the decline of the tree vigor or death. 4. Frost damage on branches: The year-long branches of fruit trees are more resistant to cold. Late-growth shoots that grow immature are most susceptible to freezing injury and die. Some shoots appeared to have no change in appearance but germinated later, and the leaves were thin or deformed. After the cut, the color of the xylem became brown. 5. Freezing damage to flower buds: The cold damage of flower buds often occurs in the early spring. Since the flower buds lift the dormancy period, the temperature in spring rises, and when frost occurs again, the flower buds suffer freezing injury. When the damage is light, the germination is slow, deformed, or stays at a certain stage of development for a long time. In the spring, it is not easy to see if it is dry, thin and easy to fall, and some appearances are not easy to see. However, the internal visible buds of the buds have turned brown, and when severe, they can die. . Second, the cause of frost damage Biofilms in fruit trees are the most sensitive to low temperatures, and low temperatures can reduce biofilm activity. The appearance of ice crystals in the cell gap causes the loss of water in the cell, which increases the concentration of inorganic and some organic compounds that are toxic to the biofilm, accumulates in the vicinity of the biofilm, and undergoes irreversible changes. This is caused by freezing damage. process. Low temperatures, cold winds, and cold winters in winter can cause freezing damage to fruit trees. Winter temperatures change dramatically, and the temperature difference is large. If the low temperature lasts for a long time, the branches of trees will be frozen. Cold winds can promote the evaporation of soil moisture and reduce soil and air temperature, which is unfavorable for over-wintering. Drought can aggravate the transpiration of shoot moisture. At the same time, because of the low ground temperature, the water supply is not timely, and it is easy to have physiological drought. As the temperature rises in spring, the cold resistance of the fruit trees will also decrease. In the event of cold currents and droughts, flower buds and shoots will be most severely frozen. Of course, in addition to climatic conditions, the local conditions of the orchard and inappropriate cultivation and management measures will aggravate the occurrence of frost damage in fruit trees. Third, protection against frost damage of fruit trees 1. Choose a suitable garden: Newly developed orchards, choose leeward sunny areas as much as possible, and avoid creating gardens with low-lying hills or shade. Because this kind of place cools down early in the autumn, the spring is born is gentle, in the winter night cold air accumulates, the accumulated temperature is lower. 2. Orchard-covered grass: Grass-covered grass can increase moisture and moisture, inhibit the growth of weeds, increase the content of organic matter in the soil, deepen the soil before covering the grass, apply enough basic fertilizer, and cover with weeds after watering. The thickness of about 20 cm, a little cover on the soil, can greatly reduce the degree of frost damage of fruit trees. 3, to strengthen the management of fertilizer and water: Practice has proved that a reasonable fertilization, irrigation, not only is conducive to the growth of fruit trees, but also to improve their ability to fight drought. Increasing organic manure, phosphorus and potash fertilizers are beneficial to the affinity of the protoplasm to water and enhance the plant's resistance to adverse environmental conditions, which is conducive to overwintering of fruit trees and increasing yield. Control of irrigation, appropriate reduction of water content in the plant tissue, can also enhance the cold resistance of fruit trees. 4, a reasonable pruning branches: pruning can increase fruit production, control of pest damage and proliferation, increase plant nutrient accumulation, is conducive to cold winter. Subtract excessively dense shoots to achieve ventilation and light control for vegetative growth. 5, spray chemical agents: Some plant growth regulators, not only can promote or inhibit the growth of fruit trees, improve yield and quality, but also enhance plant metabolism, regulate plant growth. Promote rooting, increase the sugar content and coloring degree of the fruit, and can enhance the cold resistance of the fruit tree. 6. Other measures: Before the winter, white trunks are coated with lime slurry to prevent and control pests and diseases, and to improve cold resistance and frost resistance. Saplings can also be protected by the trunk wrapping or semicircular soil protection in the north. Our Retractor And Fixer Products is good in quality and competitive in price. We are manufacturer and supplier Retractor And Fixer following your specific requirement. We are looking forward to your E-mail and establishing cooperative relationship with you! We would provide professional Laboratory Tester with good services for you! Retractor And Fixer Retractor And Fixer,Medical Leg Cushion,Hand Foot Elevation Cushion,Hospital Back Support Cushion Ningbo Cland Medical Instruments Co., Ltd. , https://www.cland-med.com