Technical plan for the prevention and control of major diseases and pests in cotton in 2021

　　In 2021, the overall occurrence of cotton diseases and insect pests in China is moderate, and the common occurrence of diseases and insects includes: cotton aphid, cotton blind aphid, cotton leaf mite, cotton thrips, cotton bollworm, underground pests (slugs, grubs, golden needle worms, ground tigers), seedling diseases (standing blight, cataplexy, anthrax), blight, verticillium wilt, bell disease (epidemic, anthrax, red rot, etc.), locally occurring diseases and insects include: whitefly, twill nocturnal moth, red leaf stem blight, etc. In order to effectively do a good job in the prevention and control of major diseases and insect pests in cotton in 2021 and ensure the safety of cotton production, ecological safety and quality safety, this plan is specially formulated.

　　1. Prevention and control objectives

　　The rate of major pest control and disposal has reached more than 95%, the area of application of green prevention and control technology and the area of specialized prevention and control have reached 30%, the overall control effect has reached more than 85%, the loss rate of disease and insect harm has been controlled within 8%, and the reduction of pesticide use has been promoted.

　　Second, prevention and control strategies

　　Adopt the strategy of "prevention first, comprehensive prevention and control, harm control and drug reduction, and protection of bell and production" to prevent and control harm during the pre-sowing and seedling stages, growth period and bell stage. Priority is given to the use of resistant (resistant) varieties, agronomic and biological control technologies, giving full play to cotton's own compensation capacity, and using ecological regulation and the ability of natural predators to continuously control damage. Implement the use of drugs that meet the standards and precise drugs, give priority to the use of biological sources and environment-friendly pesticides, promote the integration of green prevention and control and professional unified prevention and control, improve the efficiency of prevention and control, and reduce the amount of pesticides.

　　III. Prevention and control priorities

　　(1) Northwest inland cotton area. Including Xinjiang and Gansu cotton areas. Focus on the prevention and control of cotton aphids, cotton leaf mites, cotton thrips, grass blind bugs, cotton bollworms, blight, verticillium wilt disease, seedling disease, and locally do a good job in the prevention and control of whiteflies and green blind bugs.

　　(2) Cotton area of the Yellow River Basin. It includes Hebei, Shandong, Henan, Tianjin, Shanxi and Shaanxi Mian. Focus on the prevention and control of cotton aphids, cotton blind bugs, cotton bollworms, whitefly, cotton leaf mites, blight, verticillium wilt, seedling disease, and bell disease.

　　(3) Cotton area of the Yangtze River Basin. Including Jiangsu, Anhui, Hubei, Jiangxi and Hunan cotton areas. Focus on the prevention and control of cotton blind bugs, cotton leaf mites, cotton bollworms, twill moths, blight, verticillium wilt, seedling disease, bell disease, red leaf stem blight, cotton aphids, cotton thrips, tobacco whiteflies, and red bollworms.

　　4. Prevention and control measures

　　(1) Agronomic measures

　　Clean the countryside, remove the cotton stalks in time after the cotton harvest, and remove the remains of diseases and insects. Autumn deep turning, conditional cotton area autumn and winter irrigation to protect the moisture, low the overwintering base of diseases and insects. Remove weeds from the edge of the field, weed weeding in the middle of tillage, and reduce the diversion of pests. Timely topping and taking out of the field for centralized processing. The northwest inland cotton area rationally arranges cotton fields, avoids cotton and large areas of spring corn, processed tomatoes, cruciferous crops adjacent crops, and stays away from jujube gardens and concentrated greenhouses, reducing the diversion of cotton bollworms, pasture blind bugs, and whitefly.

　　(2) Ecological regulation and biodiversity utilization

　　Crops such as alfalfa or early maturing rapeseed are planted in the fields around the cotton fields in the northwest inland cotton area, and flowers such as cnidium monnieri, cosmos, and pertussis are planted in other cotton areas, providing honey sources for natural predators, attracting and conserving natural enemies, and enhancing the control ability of natural enemies to cotton aphids, cotton bollworms and cotton leaf mites. Cotton in the area where cotton bollworms are commonly occurring is planted with corn and alfalfa strips, which induce adult cotton bollworms to lay eggs and concentrate on killing. Promote the planting of cotton and winter wheat flowers to protect and utilize natural enemies.

　　(3) Select disease- and insect-resistant varieties

　　Blight-resistant and verticillium wilt-resistant varieties are selected according to local conditions, and high-quality and high-yield varieties of insect-resistant cotton with good disease resistance are selected in the cotton areas of the Yellow River Basin and the Yangtze River Basin.

　　(4) Seed treatment

　　According to the main diseases and insect species at the seedling stage of each cotton area, appropriate insecticides, fungicides, plant growth regulators or special seed coating agents are selected to coat seeds or recoat. Insecticides can be selected from imidacloprid or thiamethoxine seed treatment agents, fungicides and plant growth regulators can choose Bacillus subtilis, amino oligosaccharides, brassinolide, phenylethiconazole, clonylonitrile and the like.

　　(5) Protection and utilization of natural enemies

　　1． Protect and utilize natural predators. In the early stage of cotton growth, attention should be paid to the protection and utilization of natural natural enemies in cotton fields, and the role of natural enemies in controlling harm should be brought into full play. After wheat and rapeseed are harvested, the straw is placed in the field for 2-3 days, which is conducive to the transfer of natural enemies such as ladybirds to the cotton field. During the occurrence period of seedling aphids, when the natural enemy units in the cotton field (1 seven-star ladybird, 2 spiders, 2 aphid lions, 4 aphid flylets, and 120 aphid cocoon bees are 1 natural enemy units) and the aphid population ratio, the cotton area of the Yellow River Basin is higher than 1:120, the cotton area of the Yangtze River Basin is higher than 1:320, and the cotton area of the northwest inland is higher than 1:150, no drug control is applied, and the natural enemy is used to control aphids. In the cotton area of the Yangtze River Basin, chemical pesticides are generally not applied to control seedling aphids from the seedling stage to the bud stage.

　　2． Artificial release of red-eyed wasps. Adult cotton bollworms artificially release eggs parasitic bee borer yellow red-eyed bees or pine caterpillar red-eyed bees in the prime stage, and the amount of bees released is 10,000 heads/mu each time, and the bees are released 2-3 times per generation, with an interval of 3-5 days, reducing the amount of cotton bollworm larvae.

　　(6) Booby traps insect pheromones

　　Cotton bollworm overwintering adults from the beginning to the end of the final adult, a large area of continuous patches using cotton bollworm sex attractant, per acre set up a swing core and dry moth trap. In the cotton area of the Yangtze River Basin, the twill moth is often occurring, and a large area of continuous patches use twill moth sex attractants, 1 swing core per mu and a nocturnal moth-type trap, and the cluster traps adult insects to reduce the amount of eggs in the field. Continuous application of biological food attractants, in the nocturnal moth family pests (cotton bollworm, ground tiger, clover nocturnal moth, etc.) 1-2 days before the main pest generation feathering, drip in a strip manner, every 50-80 meters on the top of a row of cotton plant leaf surface evenly applied, can trap adult insects.

　　(7) Prevention and treatment of environment-friendly pharmaceuticals

　　1． Cotton aphids. When the benefit-harm ratio was lower than the target, when the rate of 3 true leaf pre-leaf curled plants in the cotton area of the Yellow River Basin and the cotton area of northwest inland cotton reached 5%-10%, or the rate of 4 true leaf post-rolled leaf plants was 10%-20%, the drug spot was picked. When the average amount of aphids in the upper, middle and lower three leaves of aphids per plant was 200-300, the whole field was controlled. Flufenacil nitrile, dipropylcycloxate, flufenacilamide, enidazonamide, praydazone and other agents are used alternately.

　　2． Cotton bollworm. When the 100 young larvae of transgenic Bt gene cotton exceeded 100 plants and the cumulative egg volume of 100 non-Bt gene cotton plants was 100, the drug was controlled. Preferential selection of cotton bollworm karyotype polyhedral virus, kale moth karyotype polykernoid virus, short stable bacillus, Thuringiensis (trans-Bt gene cotton field prohibited) and other microbial pesticides, chemical pesticides using lice urea, flullicilurea, indiivir, polycycline and so on for prevention and control.

　　3． Cotton blind bugs. When there are 12 heads/100 plants at the bud stage, 20 heads/100 plants at the flowering stage, 40 heads/100 plants at the bell stage, 5 heads/100 plants at the bud stage and 100 heads/100 plants in the cotton area of the Yellow River Basin, the new victimization rate in the cotton area of the Yangtze River Basin is 3% or the number of insects in the 100 plants is 5. The time of application should be before 9 a.m. or after 4 p.m., and the drug should be applied inward from Tanabe, and the agent should be selected from thiamethoxazine, flufenacilamine nitrile, etc.

　　4． Cotton leaf mites. When the spot occurs, or when the mite plant rate is less than 15%, the central plant is selected, and the mite plant rate exceeds 15%. The medicinal agents are pyridoxine, avermectin and so on.

　　5． Cotton thrips. Seed coating control is the main one at the seedling stage and bud stage, and seed coating can be selected with thiamethoxine and imidacloprid. During the flowering period, insects can be controlled according to the situation, and agents such as CQMa421 and thiamethoxazine can be used.

　　6． Seedling disease. Mainly for seed coating prevention, the selection of chlorine nitrile, fine nail cream, azoxystrobin mixing or re-coating. In the early stage of the disease, especially in the case of low temperature and rainy weather, the drug was timely controlled, and the spray was carried out by bacillus subtilis, polyantimycin, and xomyrrhinol.

　　7． Blight and verticillium wilt. Coated with Bacillus subtilis seeds. From the seedling stage to the bud stage before the onset of the disease or the early stage of the disease, spray or with water droplets of Bacillus subtilis, amino oligosaccharides, ethosin.

　　8． Bell disease. Before the onset of the disease or when the disease is first seen, the flower buds and young bells are sprayed for prevention, or the prevention before the rain during the flowering period and the timely spray control after the rain.

　　Precautions: (1) Give priority to the use of biological pesticides and pay attention to the protection of natural enemies. (2) Reasonable rotation and alternating use of different mechanisms of action agents avoid the single use of the same agent multiple times a season. (3) Strictly implement the operating procedures for the use of pesticides and comply with the pesticide safety interval.

Source: National Agricultural Technology Center