Summer is coming, what are the common pests and diseases that peppers will happen at this time? How to prevent it? The more common diseases of pepper in summer include pepper virus disease, anthracnose disease and physiological disease, which cause the pepper to be fruited in the later stage, affecting the economic value of pepper. The more harmful pests are sassafras and scorpion. Let's take a look at the prevention and control measures for the main diseases of pepper in summer. Capsicum virus disease symptom: Capsicum virus disease is mainly mosaic virus disease. It often occurs in the top leaves, and the symptoms are leaf mosaic, yellowing, and leaf rolling; the plants appear to shrink or become streaky on the fruit. When several viruses are combined, the symptoms of streaks are caused, and the symptoms of dark brown streaks appear on the leaves and fruits. In severe cases, the whole leaves are deciduous, which makes the photosynthesis of peppers severely blocked. Sometimes malformed leaves appear on individual plants, the new leaves do not stretch, are needle-like, the plants grow slowly or "crazy", or the top becomes black and necrotic. Control method: The prevention and treatment of pepper virus disease should follow the principle of “prevention of disease prevention firstâ€. From May to early June and from late June to early July, the peak period of cotton aphid, which spreads viral diseases, is also a critical period for the prevention of anti-viral diseases. Insecticides can be minimized using imidacloprid, pymetrozine thiazide 10% cypermethrin emulsifiable concentrate, and 2.5% deltamethrin emulsifiable concentrate. For peppers that have already developed disease, you can use amino oligosaccharide, morpholinium hydrochloride or 2% Ningnan toxin in 7 days, and prevent 3-4 times. Capsicum anthracnose symptom: The leaves are infected, and the first is a fading green water-soaked spot, which gradually turns brown, with a light gray in the middle, and a small black spot on the lesion. The handle is damaged and brown spots are formed. The fruit is damaged, and it is initially flooded with yellow-brown round spots or irregular spots. The spots have raised concentric circles and many black dots. When wet, the surface of the lesions overflows with red sticky substances. The lesions on the fruit are easy to dry and shrink, and some are ruptured. Anthrax is the main disease of summer peppers, especially field peppers. High temperature and rainy weather or the use of nitrogen fertilizer is too much, flooding with large water is easy to cause anthrax. Once anthrax occurs, the incidence is fast, often causing large areas of defoliation and rotten fruit, especially in the middle and late stages of pepper growth, pepper anthracnose is more likely to occur. Control method: 1. Strengthen field management. Reasonable close planting, formula fertilization, avoid high temperature and high humidity, pay attention to drainage, timely remove diseased leaves, diseased fruits and residues, and pepper dressing properly increase the use of phosphorus and potassium fertilizer. 2. Chemical control: It is best to prevent it in advance. In the early stage of the disease, it can spray 70% methyl tonazole wettable powder 600-800 times liquid, or 80% mancozeb WP 500 times liquid; it can also use silane-like fresh amine 1200-1500 times. The liquid is sprayed once every 5-7 days and sprayed 3-4 times continuously. 3. Pepper physiological disease Summer peppers are most susceptible to physiological diseases due to the effects of high temperature weather and must be highly valued. Common physiological diseases include hot day disease of pepper, umbilical rot and physiological leaf curl of pepper. Chili day burn Chili sunburn is a physiological disease that often occurs in peppers. The cause of the disease is intense direct sunlight. The symptoms only appear on the sunny side of the bare fruit, and the epidermal cells of the fruit are burned by the sunlight, causing the imbalance of water metabolism. At the beginning of the disease, the diseased part faded, slightly wrinkled, and it was grayish white or yellowish. The flesh of the ward is dehydrated and thin, translucent, tissue necrosis is hard and tight, and it is easy to break. In the later stage, the diseased part is infected with pathogens or saprophytic bacteria, and it grows black, gray, pink or variegated layer, and the diseased fruit is perishable. Control method: Reasonable close planting and intercropping; reasonable irrigation. Large ridges and double rows of densely planted plants can shade plants and reduce fruit exposure in the sun. Intercropping with high-crop crops such as corn and sorghum, using high-stalk crops in shading conditions to reduce the risk of sunburn, improve field microclimate, increase air humidity, and reduce the risk of dry hot wind. At the peak of the results, water should be poured in small water and watered in the morning to avoid watering in the afternoon. Especially for sticky soils, it should prevent hypoxia caused by excessive watering. Spray the fungicide + foliar fertilizer in a timely manner, spray once every 7 days, and spray 2 or 3 times. Pepper umbilical rot Open-pitched peppers often occur in the growth and development period, also known as umbilical rot. The pedicel of capsicum is the same as that of tomato, which is caused by calcium deficiency. Conditions such as high temperature, dryness, multi-fertilizer and multi-potassium will inhibit the absorption of calcium and produce pedicel. Sometimes, the vegetative growth of the plant is too high, and calcium is distributed into the leaf buds. Only a small amount of calcium is distributed in the fruit, and in this case, rot is also produced. Control method: Apply more organic fertilizer to make calcium in a state of being easily absorbed. Foliar calcium supplementation: After entering the result period, 0.1%-0.3% calcium chloride or calcium nitrate aqueous solution is sprayed once every 7 days, 2-3 times a week. It can also be applied continuously with calcium fertilizer, which is very effective and can avoid umbilical rot. Chili physiological leaf The leaves of the pepper are rolled up in a longitudinal direction, thickened, brittle, and hardened: Sometimes in the upper part of the plant, the growth and development of the plant is stopped, the petiole and veins are hardened, it is easy to break, the leaves are twisted, and the flower buds and leaves fall off. Control method: Strengthen fertilizer and water management to prevent defermentation and dehydration. In the result period, the soil is often kept moist. As a result, the foliar topdressing should be carried out at the peak period to supplement the lack of nutrients in the roots. Chili tea jaundice In summer, there are many insect pests in the open air. In addition to aphids, cotton bollworms and thrips, tea jaundice is also prone to occur. The sassafras is not easy to be found in the early stage, and it is not visible to the naked eye at first. However, once it occurs, it will cause large areas of yellow leaves and fallen leaves of peppers. In the later stage, it is often impossible to prevent them. Therefore, tea jaundice should be prevented in advance. Prevention: 1. Select healthy seedlings, remove weeds and field litter in the fields, level the land, and destroy the wintering places to eliminate the wintering insects. 2. The insect has a short life cycle and strong fertility. Special attention should be paid to early prevention and control. It should be prevented once every 7 to 10 days for 3 consecutive times. The following agents may be used: bifenazate; bifenthrin; avermectin, or avidin. Large amount of water, low concentration, break through the net, the back of the leaf should be sprayed thoughtfully, spray once every 7~10 days, even spray 2~3 times to achieve better control effect. The above is all the content of today. The recent temperature is getting hotter and hotter. These common diseases have already occurred in the pepper fields in some areas. If you are not ready, you should study hard! Flame Retardant Net,Fire-Retardant Insect Screen,Flame Retardant Climate Screen,Shading Aluminum Thermal Screen Changzhou Green Nets Co.,Ltd. , https://www.czglnets.com
