In recent years, the types of cucumber diseases in greenhouses have increased year by year, which has brought about various degrees of damage to cucumber production. Now we introduce the symptoms and prevention and control experiences of several diseases and pests for the reference of farmers.
The early stage of bacterial keratopathy is a fresh green water immersed spot, which gradually turns light brown. The lesion is limited by veins and is polygonal, gray-brown or yellow-brown. When the humidity is high, the leaves overflow with milky white turbid beady bacteria liquid. After drying, it has white marks, and the disease department is brittle and easy to perforate. The lesions on stems, petioles, and fruits were water stained round spots, white mucus when wet, and white after drying. Control: It can be sprayed with 1000 times of streptomycin soluble powder or 500 times of 30% DT fungicide or 1000 times of 5% chlorothalonil dust agent in the early stage of disease, which has higher control effect.
Fusarium wilt is extremely viable and can survive in soil for more than 5 years. High temperature and high humidity are favorable conditions for the occurrence of blight. Excessive nitrogen fertilizer, acidic soil disease is more serious. The occurrence of root-knot nematode-rich plots and flood-fed land is heavier. Prevention and control: In addition to the selection of disease-resistant varieties, it is possible to adopt crop rotation with non-melon vegetables for more than 3 years to reduce the accumulation of pathogens in the soil; in the early stage of disease, use 50% carbendazim WP 500 times or 70% thiophanate-methyl WP 800 times spray, can also be used 70% Dukesson WP 1000 times or 50% ripping net 800 times Irrigation, irrigation 250 ml per plant, every 7 days irrigation 1 times, continuous irrigation 3 times. Grafting is also an ideal method for preventing cucumber wilt disease. Rootstock is a rootstock with low temperature and resistance to wilt and blackcurrant pumpkin. Cucumber is the scion, which is connected by grafting or grafting. The disease prevention effect is excellent.
In the early stage of the downy mildew, irregular spots with light yellow irregular shapes appear on the back of leaves or leaves. With the development of the disease, the lesions gradually expand and are limited by the veins to form a polygonal yellow spot. When the disease is severe, the small lesions merge into large lesions. In the wet conditions, the back of the lesion grows a layer of gray and black mold. Diseased leaves develop from bottom to top, and the leaves of the whole plant die when they are severe. Prevention: The first application of base fertilizer, appropriate application of phosphorus and potassium fertilizer, strong seedling cultivation, watering under the membrane to reduce the number of watering. Strengthen ventilation and reduce air humidity. Followed by chemical control, specific choice can be used 25% WP wet dexamethasone 800 to 1000 times, 75% chlorothalonil WP 500 to 600 times, 72% WP WP 600 to 800 times, 72 % Pric water 600 to 1000 times spray. Can also use 20 to 30 grams of chlorothalonil smoke agent shed per acre each time. The drug is administered once every 7 to 10 days, and 3 to 5 times of continuous prevention and treatment are performed.
Root knot nematode disease Cucumber root knot nematode disease symptoms mainly in the root, mild symptoms of the disease strain is not obvious, serious disease strains are shorter, poor growth, poor fruiting, wilting at noon under drought conditions. Pulling up the diseased melons will result in the emergence of necrotic root nodules of different sizes on the lateral roots or fibrous roots. Some appear beaded, making the roots thicker and dissecting the root knots, revealing that there is a small milky root knot nematode in the diseased tissue. Prevention: Deep-turning soil, free irrigation, increased organic fertilizer, etc., root knot nematode disease during cucumber growth, 50% phoxim EC 1500 times or 30% Jiasheng Microcapsule Suspension 500 Doubling liquid irrigation, each strain of 0.25 to 0.5 kg of irrigation liquid, usually irrigation can be 1 time.
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