What are the main diseases of spinach? What is the method of prevention and control?

Spinach is a kind of vegetable with obvious seasonal ratio, but later, with the progress of planting technology and the research and development of varieties, it can basically be planted in the four seasons. Spinach has high nutritional value and can supplement iron, so what are the main diseases in the process of planting? What is the method of prevention and control?

What are the main diseases of spinach?

1. Downy mildew of spinach

Downy mildew of spinach is a fungal disease caused by oomycetes. The pathogen overwintered with hyphae on diseased leaves and seeds or oospores in diseased residual leaves. The mildew layer on the back of the plaque is the sporangium and sporangium of the pathogen. The sporangium spreads by airflow and produces new plaques. Condensation and high humidity are important conditions for bacterial infection. Downy mildew of spinach mainly harms leaves. The disease is serious under the conditions of high planting density, poor field ventilation, low-lying stagnant water, low temperature and high humidity.

2. White spot of spinach

Spinach white spot is a fungal disease, the pathogen overwintered in the soil with mycelium, and spread by wind and rain in the next spring. The disease is easy to occur under the conditions of weak growth, warm and humid conditions.

The symptoms of white spot disease of spinach are mainly on the leaves. The lower leaves developed first, the disease spot was small and round, the edge was obvious, the middle of the disease spot was yellow-white, the outer edge was brown to purple-brown, and gradually developed into white spot after expansion. When the humidity is high, the gray hair can be seen on some disease spots; when the dry-wet transformation is fierce, it is easy to break in the center of the disease spot. The germs spread mainly by wind and rain. The disease is easy to occur under weak growth, warm and humid conditions, low-lying terrain, wind and poor management.

3. Botrytis cinerea

It is mainly harmful to leaves. The primary light brown irregular spot, then expanded into a light brown wetting spot, and produced a gray mildew layer on the leaf back disease spot, namely the pathogen conidiophores and conidia. The seriously diseased leaves become dark brown and rotten, lose water and blacken under dry conditions, and a lot of gray mildew can be seen.

What are the main disease control methods of spinach?

1. Control methods of downy mildew of spinach.

The main results are as follows: (1) attention should be paid to the prevention and control of spinach downy mildew: selection of disease-resistant varieties, reasonable crop rotation, reasonable close planting, and increased application of phosphorus and potassium fertilizer. Carbendazim and sodium sulfonate were used to treat the soil to improve the seed germination rate, timely sowing and reasonable close planting.

(2) at seedling stage, we should pay attention to reasonable irrigation and topdressing fertilizer, the proportion of nitrogen, phosphorus and potassium should be reasonable, and foliar fertilizer should be sprayed timely to promote plant robust growth, improve disease resistance, thicken leaves, fresh leaf color and strong natural taste.

(3) Pharmaceutical control: at the initial stage of the disease, 50% Mecter wettable powder 800 times or 50% Anke wettable powder 2500 × 3000 times can be sprayed once every 7 to 10 days, 2 times for 3 times. Reduce the spread of downy mildew. Downy mildew can be treated with 58% Lusujing wettable powder 500 times, or 60% Coruba 500 times, or 72% urea manganese zinc 600 times. Alternately, once every 7-10 days, spray 2-3 times continuously.

2. Control methods of spinach white spot.

(1) strengthen the management and improve the disease resistance of plants.

(2) remove the disease and debris in time after harvest and concentrate on burying or burning, so as to reduce the source of the disease.

(3) in the early stage of the disease, spray 75% carbendazim wettable powder 500 times, or 50% carbendazim 800 times for prevention and treatment.

3. Control methods of spinach gray mold.

The main results are as follows: (1) select moisture-tolerant varieties such as spinach.

(2) strengthen field management to avoid low temperature and high humidity conditions. Low temperature not only weakens the vitality of the plant, but also lasts for a long time, the plant is in a state of immortality for a long time, and its resistance is weak, and it is easy to be infected with Botrytis cinerea in case of high temperature, so it is necessary to do everything possible to increase the temperature and reduce humidity in the field or greenhouse. It is the fundamental measure to prevent and cure the disease. (3) remove the diseased body in time after spinach harvest, burn it centrally or bury it deeply.

(4) reasonable watering and fertilization, timely drainage after rain to prevent the occurrence of disease conditions.

(5) at the initial stage of the disease, spray 500 times solution of Tex, or 800 times solution of 20% blue tide (pyrimidine), or 600 times liquid of pyrethromycin for prevention and treatment.