At present, citrus has entered the summer shoot hair and young fruit growth period. As the temperature rises, the rainy days alternate, and the weather is high and humid, which is conducive to the spread of citrus diseases and insect pests. From May 20 to 21, the orchard survey in Binzhou, Zhonghua and other towns in Binyang County found that the main pests and diseases of citrus are: wood lice, mites, thrips, aphids, leafminer moths, aphids, canker diseases and anthrax, and each town should guide fruit farmers to carry out targeted prevention and control according to the actual situation in the field.
1. Citrus psyllid and yellow dragon disease: Citrus wood lice is the only vector insect for the transmission of citrus yellow dragon disease, which likes to lay eggs and breed on new shoots and spread yellow dragon disease. At present, it is the summer shoot extraction period, according to field surveys, the occurrence of wood lice is more common, and the density of insect mouths is significantly higher than that of the same period in previous years, especially in unmanaged orchards, with a maximum of 23 heads per plant and an average of 0.78 heads per plant (the control target is less than 1 head per 100 plants). Therefore, all localities should attach great importance to the prevention and control of pygosites 1-2 times during the summer traction period to cut off the way of transmission of citrus huanglongbing disease.
2. Citrus mites (red spiders, rust spiders): May to June is the key period for the occurrence and control of mites in the first half of the year, and the predicted degree of occurrence is 3 (4), that is, moderate local heavy occurrence, with an area of 55,000 mu. Red spider insects need to be controlled at a population density of 2-3 heads per leaf. The juvenile stage and the fruit expansion stage are the main control periods of rust spiders, and the insect population density reaches 2-3 heads per leaf.
3, citrus thrips: citrus thrips have become the main pest of citrus in our county in recent years, is one of the "culprits" caused by flower peel fruit, to be paid great attention to. The larval stage is the main period for the occurrence of pests of the insect, and it must be controlled in a timely manner in the near future.
4. Citrus aphids: The summer shoot extraction period is the peak period of citrus aphids, and the number is the largest at this time. According to the survey, the current xia shu victimization rate is as high as 48%, an average of 13%, and should be sprayed immediately for prevention and control.
5. Citrus leafminer moth: mainly harmful to new shoots and young leaves, which occurs widely in the summer shoot extraction period, larvae sneak into the leaves to eat leaf flesh, form a white insect path, the whole leaf curls and deforms, and it is necessary to prevent and control it as soon as possible.
6. Citrus beetles: Adult citrus sativae are white, arrow-shaped, and wide at the front and back. It often begins to occur on shady plants that grow vigorously in citrus groves and then spreads around the entire orchard, and must be controlled in time during the larval bloom period (mid-May-mid-June).
7. Citrus canker disease: harmful citrus leaves, branches and fruits, rough lignification on the surface of the disease spots, central depression, late cracking like a crater, the occurrence of citrus is particularly serious, the degree of predicted occurrence is 3 (4), that is, moderate local heavy occurrence, the occurrence area of 30,000 mu. Spraying 1-2 times during the summer shoot extraction period can play a role in fruit preservation.
8. Citrus anthrax: citrus anthrax is mainly harmful on the leaves, and the pathogens are spread by wind and rain, insects, and invade the leaves from wounds or skin holes, and the disease spots formed are arranged into concentric chakras of black dots. To prevent and treat 1-2 times in the near future.
Prevention and control methods:
1, citrus psyllids and yellow dragon disease: the selection of thiazidone, imidacloprid, thiamethoxine and other agents with water spray to prevent pyllids, found yellow dragon disease disease plants, should first control the pyllid, and then immediately dig up.
2. Citrus mites: avermectin, acetamide, spironate, bromofertilate and other agents are used for control with water spray.
3, citrus thrips: the use of thiamethoxine, imidacloprid, acetamidine and other agents with water spray control.
4. Citrus aphids: use imidacloprid, acetamidine and other agents to mix with water spray control.
5. Citrus leafminer moth: spray control of avermectin, imidacloprid and other medicinal solutions.
6. Citrus ticks: use thiazide ketone, Avi • Chlorpyrifos and other agents to spray control with water
7. Citrus canker disease: spring thunder wang copper (Garrinon), copper hydroxide (can be killed) and other medicinal spray prevention.
8. Citrus anthrax: selected daisen manganese zinc plus imidoxamine (or phenoxymethaciazole) with water spray prevention.
Wood lice on citrus shoots
Source: Binyang County Plant Protection Station