1. Blight
Cotton blight, commonly known as rot disease and black root disease, occurs in all cotton regions of the country. After cotton seedlings are damaged, yellowish-brown lesions develop on the stem base near the ground, and then turn into dark brown, and gradually rot and rot. When the disease became thinner, the diseased seedlings died or fell down. Cotyledons form an irregular, yellow-brown lesion after victimization, and later the diseased department breaks off and becomes perforated. In the adult period, brown spots appear on the leaves, and the perforations are exfoliated.
Control methods: 1, a reasonable rotation: with grass crops: rotation for 2 to 3 years. 2, a reasonable fertilization: fine soil preparation, increase the application of organic fertilizer or 5406 fertilizer. 3, improve the quality of sowing: spring cotton to 5 cm deep Shishida 14 °C suitable for sowing, general sowing 4 ~ 5 cm deep is appropriate. 4, to strengthen seedling management: appropriate early seedlings, diligent cultivators, reduce soil moisture, increase the temperature, nurturing strong seedlings. 5, seed dressing seed dressing, with a seed weight of 0.5 to 0.8% of 50% carbendazim, or seed weight of 0.6% of 50% thiophanate-methyl, seed dressing.
Second, wilt
Fusarium wilt, also called plant cancer, is the enemy of cotton production and has spread rapidly in recent years. Fusarium wilt is characterized by: dwarfing plants, grayish-green leaves, brittleness, stalk bending, shortening of stem knots, depression of the roof, and vascular bundles in stems turning grayish brown or light black. Incidence conditions: high temperature and high humidity, even planting, sunny days after the rain, will die, into a film death.
Prevention methods: 1. Soil improvement: Based on the application of organic manure, nitrogen, phosphorus, and potassium, an additional 0.5 kilograms of weight herbicide per acre will be added, and then ploughing can remove most of the soil bacteria, and can make the soil Increase the air permeability, eliminate the content of alanine in the soil, remove the hardened, improve the saline-alkali, enhance the resistance of the plants, and reduce the damage of the yellowish wilt. 2, the amount of nitrogen fertilizer. 3. Watering at an appropriate time. On average, there are two bells per plant. The first water is poured when the weather is dry. The watering will promote the occurrence of disease. 4. The seedling, bud and flowering period are sprayed 2-4 times with the first aid. Or hymexazol, etc., prevent yellow wilt. 5, on the diseased plants can be surgically controlled, set on the base of the cotton stem 5 to 6 cm with a knife to open 2 to 3 cm longitudinal mouth, insert two with the yellow liquid first aid soaked for more than 4 hours of the matchstick, take The above methods can effectively control the damage of cotton wilt, and can also control the blight of other crops.
Third, black rot
Black rot cotton roots are black in the epidermis, slightly raised, no new roots grow, the plants are short, the leaves are soft, slow-growing, and easy to die at high temperatures. After death, the plants appear black and dry, and the uprights do not fall. Blocky. After long periods of rain, the water was long, the terrain was low, and the saline-alkali or heavy nitrogen fertilization plots were not in time. Before the planting of sweet potato, sugar beet, Chinese cabbage, cabbage, and radish plots, the disease was prone to develop.
Control methods: 1, leveling the land, prevent water accumulation, timely drainage. 2. After the rain, the cultivating loose soil breathes in time to increase the root activity. 3. Increase the use of lime powder 15 kilograms per mu, 10 kg of ferrous sulfate or the application of heavy scorpion agent, fertility treasure can reduce and control the occurrence of the disease. 4, increase organic fertilizer and phosphorus and potassium fertilizer, control and appropriate application of nitrogen fertilizer; 5, the incidence of yellow with first aid, rot speed Kang 20 grams each, add 15 kilograms of water, spraying foliar or irrigation roots can effectively prevent black rot.
IV. Viral diseases
Cotton virus disease mainly includes lobular virus disease, mosaic virus disease, beetle disease wilt disease, purple leaf disease virus defoliation, falling flower, fruit drop virus disease, virus disease called plant AIDS, rapid spread, serious damage, reduced production invisible It is the first enemy of the plant.
Control methods: The use of virus doctors, anti-toxins, virus extinguishers, and blight disease can be prevented in the early stage of cotton growth.
Fifth, stem blight
Cotton can be damaged from the seedling stage to the end of boll-lining period. The early stage is the damage to the cotyledons, true leaves, stems, and growing points, resulting in rotten species, leaf spots, stem blight, decapitated deciduous trees, and even the entire plant withered. Late infestation of loquat leaves and young bells Causes defoliation and deadlock. Cotyledons and true leaves at the beginning of the disease are yellow-brown small round spots, with purple edges, and then expanded into round or irregular brown spots. Many small black spots (pathogens) are scattered on the surface. The stems and petioles were affected. The lesions were reddish-brown at the beginning, and later expanded into dark brown spindle-shaped ulcers, central depressions, and purplish reds. When the condition is serious, the diseased part is broken off and the stems die.
Control methods: 1, rational rotation, rational close planting, improve ventilation and light conditions. 2, seed dressing, cottonseed sulphur after degreasing, mixed with carbofuran and carbendazim ratio of 1:0.5 seed coating agent, both disease prevention can also treat aphids. 3, spraying, seedling stage or adult disease, 65% can be used on behalf of Sen 800 times, or 70% thiophanate-methyl 1000 times spray control.
Face Mask,Mouth Mask,Surgical Face Mask,Face Mask Disposable
Shaoxing Gangfeng Hospital Products Co.,Ltd. , https://www.gangfenggauze.com