The occurrence and prevention of cotton aphid
I. Occurrence of cotton aphid in cotton fields Fangcaohu Farm Cotton aphids occurred between 2000 and 2003, occurred moderately mild in 2000, occurred moderately in 2001, occurred exceptionally lightly in 2002, and occurred young in 2003. In recent years, cotton field cotton aphids began to appear in the early stage of budding (the end of May), and mainly occurred in budding period (early June), flowering period (July and August), and boll opening period (mid-September and mid-September). Cotton plants in the center of the field have generally been seen in early June. Winged beetles generally spread in Honda and nearby cotton fields in mid-June or early July. They will enter the flood season from the beginning of July to the end of July, and the migration peaks will be from mid-July to late July. Before the end of June, cotton aphids took center stage in the cotton fields, and gradually entered the full occurrence period in early July. The most intense occurred in late July and early August. Cotton jackets generally subsided in early September. Mild occurrence of cottonseed in 2003: In June, only a small number of central strains occurred in the cotton fields. In the first few days of July, the cotton aphids in a few cotton fields gradually began to spread into dots. From July 13 to 16, there were only a few wings in the area. Qian moved to the end of July and basically subsided. 2. The relationship between the occurrence of cotton aphid and climate The occurrence and growth of cotton aphid in cotton fields are affected by many factors, such as the base number of overwintering, climate, cultivation techniques, natural enemies and prevention and control methods. However, the climate factors are very important. The main factor affecting the growth and decline of cotton pupa in June is the temperature, and the amount of precipitation has no obvious effect on it. The period from July to September is the peak of the migration of cotton aphids. The occurrence and growth of cotton aphid are affected by the temperature and precipitation. For example, in July 2003, the average temperature was 24.3°C, and the monthly precipitation was 52mm. The average temperature in August was 22.8°C and the monthly precipitation was 8.2mm. In July 2002, the average temperature was 25.2°C, the monthly precipitation was 24mm, and the average temperature in August. At 21.8°C, the monthly precipitation is 22.5mm. In August of these two years, the occurrence of cottonseed meal was lighter. 3. Key prevention and control methods for cotton aphid and control methods 1. Elimination of overwintering in Wuyuan Fangcaohu Farm is cold in winter. Cotton aphids winter in the living room, greenhouse, greenhouse flowers and crops. When the spring is warm, the flowers are moved out of the house or opened. When ventilated, the jacket moves into the cotton field. Therefore, before the cotton aphid migrated into the cotton field, the cotton aphid on the flower was fully and thoroughly eliminated in mid-late March. The cotton aphid on the greenhouse crop in early May must be completely and thoroughly eliminated. Flower scorpion with 3% carbofuran granules 2 to 4 grams per pot, greenhouse spray for a spray agent, available 80% DDVP EC 1000 to 1500 times. 2. Prevention and control of the central pupa-to-winged pupa From the middle of May, the investigation of the cotton fields, especially the cotton fields near the residential areas, was intensified. Once the central loquat plant is found, it should be well marked, timely controlled, and monitored as a key field. Do a piece of it and completely cure it. During this period, the “prevent, check, wipe, pick, pull, drip†six-word prevention and control method was adopted. If there are few strains in the center, you can use 1:100 of 40% omethoate cream, or wipe or remove by hand. In cotton fields where cotton aphid occurs early and there are more spreads in the central plant, the hazard ratio in cotton fields should be carefully investigated as soon as possible. If the beneficial/harmful ratio is 1:600 ​​and the beneficial insects have an upward trend in the cotton fields, they may not need to prevent them and give full play to their natural enemies. (3) The prevention and control of the migration of Daoyu in the initial stage of the general migration from early June to late June, with the increasing temperature, the rapid development of cotton aphid breeding, winged clams continue to produce, and spread in residential areas and to nearby cotton fields. This period is the focus of the prevention and control of cotton aphid, but also the difficulty of prevention and control. Yellow-board seizures should be used as an important means of forecasting, that is, placing a sampaning board around the residential area where the cotton locust occurs and adjacent to the cotton field. In order to ensure the effect of the decoction caused by yellow plates, it is necessary to continue the prevention and control of the central loquat strains and spottings while attracting yellow plates. The more thorough prevention and control of cotton aphids, the less fins they produce, and the slower the spread of the central cotton field into spots. 4. Interesting and comprehensive prevention and control of spread After the beginning of July, the winged pods of cotton fields gradually entered the peak of migration, and they spread and spread from the end of July to the beginning of August. The method of fumigation and spraying of poisonous soils can be used. 5. To protect and utilize natural enemies, and to control and harm them with benefits. (1) A small amount of cotton black pods and cotton long tube pods often occur at the seedling stage of cotton. Generally, they do not need to be protected, which is conducive to attracting and breeding natural enemies. (2) Prevent and control the spread of cotton aphid by spotting at the stage of spotting of cotton aphid in the field. General use of 40% omethoate 1:100 times the heart of the heart, wash urine mixture spray control, in order to protect natural enemies. (3) Under the circumstances that cotton aphids in cotton fields generally occur due to certain special factors, pesticides that have strong lethal aphid and less toxic to natural enemies can be used to reduce the number of pesticides to protect farmland ecology and protect natural enemies. Effectively adjust the proportion of harm in the cotton field, and then let the natural enemies rise quickly to a level that can completely control the damage. If natural enemies are difficult to control, appropriate methods of chemical control should be adopted according to the climate and the physiological state of cotton plants. (4) In the prevention and control of other pests in cotton fields, the protection of natural enemies and the role of concurrent administration should also be considered. The use of pesticides that have a small impact on natural enemies and can be controlled, such as the use of specific acaricides to control cotton leafhoppers, can help protect natural enemies. In short, the prevention and control of cotton aphid is carried through the entire process of cotton production. It is an important part of the comprehensive control of pests and diseases of cotton fields. It must be based on the strengthening of field investigations, adherence to agricultural control, biological control as the center, and the use of crops ( The mutual regulation between cotton, other crops, pests (cotton aphid, cotton leafhopper, cotton bollworm), natural enemies (ladybugs, grasshoppers, spiders, etc.), fully exerts the inhibitory effect of ecological factors, and achieves harm control. Benefits, improve social, economic and ecological benefits.