Apple leaflet disease is a physiological disease caused by insufficient zinc content in the tree body. Therefore, zinc supplementation is often used to prevent and control. But apple tree leaflet disease is not only caused by insufficient zinc content. Unreasonable pruning measures, such as improper branching and heavy ring stripping, can also cause leaflet disease. Therefore, according to the characteristics of lobular disease, first figure out what causes the lobular disease, and then control the situation. 1. Characteristics of lobular disease After the lobular disease occurs, no matter what kind of lobular disease symptoms are basically the same, it is that the diseased branches germinate late in spring, after the leaves are stagnated, the quality is thick and crisp, the leaves are uneven in color and yellowish green, and the diseased branches are internodes Short, the leaf margin rolls up, and the leaves are small and cluster-like. Second, the difference between the two lobular diseases Leaflet disease caused by zinc deficiency in the tree is caused by soil zinc deficiency or the inability of zinc salts in the soil to be converted or used, or the imbalance between the elements. It is difficult to recover without soil improvement and supplemental corresponding zinc elements. Because the fertilization program and the amount of fertilizer in an orchard are basically the same, lobular disease caused by zinc deficiency is manifested in one area or one area, not individual plants, but the severity of symptoms is different, often due to low to high terrain, soil performance From infertility to fertility, water supply conditions from low to heavy and from heavy to light, and there are often bare areas with no leaves at the back of the lobular disease branches. Unreasonable pruning leads to leaflet disease. One is excessive sparse branches or excessive sawing during winter pruning, and there are wounds on the mouth, continuous mouth wounds, etc., which seriously weakens the growth of the central or backbone branches, causing changes in physiological functions, resulting in Leaflet. The second is that the ring peeling is too wide during summer shearing, the peeling protection is not enough, or the tree body between the ring peeling is lack of water, etc., so that the healing of the peeling is poor, causing the growth of the part above the peeling to be blocked, metabolic disorders, and lobular disease. The ring stripping width of dry land fruit trees is too large, and most of them have small leaf disease. The biggest difference between this type of lobular disease and zinc-deficient lobular disease is that the symptoms appear on individual plants or individual backbone branches, and more than 2 to 3 strong new shoots can be drawn below the large sawing or ring peeling. Most of them are sprouting buds, and it is more difficult to germinate the posterior branches of zinc deficiency leaflet disease plants. 3. Prevention and treatment of lobular disease Leaflet disease caused by zinc deficiency should be controlled by soil improvement and supplement of zinc fertilizer. The main measures are: â‘ Increase the application of organic fertilizer, improve the soil, strengthen soil and water conservation, and enhance tree vigor. â‘¡ Combined with autumn fertilization, supplement zinc fertilizer. In autumn, mature tree plants are applied with 0.5-1 kg of zinc sulfate. â‘¢ Combined with fertilization, supplement zinc fertilizer. Before the tree germinates in early spring, spray 3% zinc sulfate + 3% urea solution on the trunk and branches. In addition, you can also irrigate 2% to 5% zinc sulfate solution before germination, spray 1% zinc sulfate when the flower buds are red, spray 0.2% zinc sulfate + 0.3% urea solution during the flowering period of apples, use 0.2 after 3 weeks of flowering % Zinc sulfate + 0.3% urea solution. For leaflet disease caused by unreasonable pruning, the following measures are mainly adopted for prevention and control: â‘ Correctly select the left and right cuts to avoid mouth wounds, continuous mouth wounds and one-time removal of thick branches. When removing large branches, you can use the method of leaving piles or throwing braids, depending on the thickness, and remove them in 2 to 3 years, and apply 3% zinc sulfate solution to the shearing mouth before taking wound protection measures. â‘¡ When pruning trees that have caused leaflet disease due to improper pruning, light shearing should be the main method. The pruning method combined with four seasons is used to slow down the branches with leaflet disease, and can not be cut short, and strengthen the comprehensive management. After the branches return to normal in 2 to 3 years, they can be pruned according to the routine; the strong and vigorous branches germinated at the rear can also be used to update . â‘¢For trees with excessive ring peeling and poor healing, the bridge should be bridged up and down, and the peeling with poor healing should be wrapped with plastic film. â‘£ Strictly control the load of the tree body and maintain a strong tree vigor. Disclaimer: Some articles of this website are transferred from the Internet. If the legal rights of third parties are involved, please inform this website for processing. phone Triangle Half Lead Apron,450*450 Triangle Lead Gonad Shield,0.35Mmpb Half Lead Apron,Triangle Anti-Radiation Medical Shield Cover Longkou Kangxie Medical Instrument Co., Ltd , https://www.lkmradiology.com