What should I do if Ponkan gets Huanglong disease?

A: comrade Nong Wenguang: Hello, citrus Huanglong disease is a destructive disease, which spreads rapidly, and existing citrus varieties are susceptible to the disease. therefore, comprehensive measures must be taken to control citrus Huanglong disease in order to achieve good results. 1. Strictly carry out quarantine, and strictly prohibit the transfer of seedlings and diseased materials (such as scions) from the disease area to the new area and disease-free area. In the disease area, seedlings with or may be diseased should be planted relatively centrally in a controlled area to prevent further spread. All newly opened orchards should be planted with disease-free seedlings. 2. Establishing disease-free nursery and cultivating disease-free seedlings are the key measures to control citrus Huanglong disease. It is necessary to cultivate disease-free seedlings without Huanglong disease and some dangerous diseases (such as canker, split skin disease, etc.). For new orchards in new areas and disease-free areas. 3. Dig out the diseased plant. In view of the fact that there is no effective way to treat citrus trees with Huanglong disease. And the diseased tree left in the field is a source of disease. Therefore, as soon as the tree is found to be Huanglong disease, digging it immediately is an important measure to prevent the spread of Huanglong disease. The practice is: every year in spring, summer and autumn, especially in autumn, carefully check plant by plant, find diseased plants or suspected diseased plants, dig up and burn them immediately. Before digging up diseased trees, 40% omethoate and 1000 times of omethoate should be sprayed on the diseased trees and nearby plants to prevent citrus planthopper from spreading from the diseased trees. New citrus orchards with disease less than 10% and old citrus orchards with disease less than 20% can be replanted with disease-free seedlings after diseased plants are removed. 4. Control citrus planthopper. Citrus planthopper is an insect that spreads Huanglong disease. Grow on the new buds and shoots of citrus. The shoot is controlled by controlling water and fertilizer, so that the new shoot is neat and consistent, and the shooting period is shortened. When the new shoot is drawn to 1Mel 2cm, spray 1Mel insecticide twice. In winter, citrus planthoppers like to fly to Jiuli incense near the orchard to spend the winter. Spraying insecticide on Jiuli incense plays a certain role in reducing the number of wood lice. In addition, planting shelterbelts around the orchard can hinder the migration of wood lice. 5. Strengthening the management, especially the water and fertilizer management of the fruiting trees, keeping the trees strong and vigorous and improving the disease resistance, play an important role in reducing the occurrence of Huanglong disease and the loss caused by the disease. 6. Transform the ward into a new area. For some orchards where citrus Huanglong disease is very serious and has lost its economic value, the disease area should be rebuilt, that is, all the citrus trees in the whole orchard (including those that may have been infected but have not shown symptoms) should be excavated, and then replanted with disease-free seedlings. By doing a good job in pest prevention, digging up diseased trees in time and strengthening management, the disease area can be transformed into a disease-free new area. The above is for reference only.