What are the common pests and diseases of spinach? How to control? The following is mainly from the three main diseases of spinach to tell you about the integrated control measures for common spinach diseases, I hope you have planted spinach to help Oh!

A, spinach white spot disease

Harmful symptoms: spinach white spot disease is mainly manifested in the leaves. The lower leaves first, the spot is round to nearly round, the middle of the spot yellow-white, the outer edge of the brown to purple-brown, expanding gradually developed into a white spot. When the humidity is high, gray hairs can be seen on some spots, and when the wet and dry changes are intense, the middle of the spot is easy to rupture. Spinach white spot disease fungus to mycelium with the disease residue in the soil overwintering, the following spring the disease spread by wind, rain spread. Weak growth, warm and humid conditions are easy to develop, low-lying, harboring wind, poor management of the disease.

Prevention methods: choose a flat terrain, adequate organic fertilizer ventilation plot planting spinach, appropriate watering, fine management, improve plant resistance. After harvesting, remove the disease residue in a timely manner, centralized deep burial or burned to reduce the source of disease. In the early stage of the disease, spray 30% of the suspension of the green to protect 400 ~ 500 times liquid, or 1:0.5:16 Bordeaux liquid, 75% Chlorothalonil wettable powder 700 times liquid.

Two, spinach wilt

Symptoms: Spinach wilt generally occurs more seriously in the adult stage. The performance of the old leaves darkened and lost luster, leaf flesh gradually yellowing, gradually expanding upward, downward development of the root brown this death. Early onset of the plant is obviously dwarfed. When the weather is dry and the temperature is high, the diseased plants rapidly shrivel up. In humid and low-temperature conditions, the diseased plant can continue to survive for a period of time, and sometimes can grow new lateral roots. But a hot weather that is quickly withered.

Prevention methods: 3~5 years crop rotation with onion and grass crops, avoiding continuous cropping. Application of Japanese enzyme bacteria compost or fully rotted organic fertilizer, and the use of formula fertilization techniques to improve host resistance. Use raised beds or ridge cultivation, timely drainage after rain, and strictly prohibit flooding. Finding the center of the disease plant timely pulled out, disease holes and around the drenching 50% benomyl wettable powder 1500 times liquid, 40% polysulfide suspension 500 times liquid, or 10% of the chlorosis of the water 300 ~ 400 times liquid, sprayed every half a month, for 2 ~ 3 times.

Three, spinach downy mildew

Harmful symptoms: spinach downy mildew is the highest incidence of spinach disease, the disease is caused by a fungus called spinach downy mildew. The symptoms of field damage are: the main damage to the front of the leaf blade, lesions yellowish; lesions expand, connected to each other into a piece, and later turn brown and die. Leaf blade abaxial spot produced gray-purple mold layer. The disease gradually develops from the outer leaves to the inner leaves, expanding upward from the lower part of the plant. Drought leaves withered yellow, high humidity, more rot, serious whole plant leaves turn yellow and die.