The latest control methods of lettuce pests

Lettuce is a kind of vegetable with high economic benefit. It has high edible and planting value. It is widely planted in China. However, once it is disturbed by diseases and insect pests during planting, it can not be eaten basically. Therefore, attention should be paid to the prevention and control of diseases and insect pests during planting. So what are the pests of lettuce? Let's take a look at common pest control methods for lettuce.

1. Soft rot

Soft rot mainly occurs in the late growth stage or heading stage of lettuce. Its pathogen mainly lurks in the soil or diseased plants for winter, and spreads infection through watering and fertilization. Generally, when the plant appears wound, the infection invades from the wound. At the beginning of the disease, the infected part was infiltrated and translucent. With the development of the disease, irregular water-stained spots were formed, and brown viscous substances appeared, accompanied by foul smell, which finally led to the decay of the whole seed ball.

Control methods: ploughing and soil preparation, using sun sterilization, removing diseased plants, reducing pathogens, strengthening fertilizer and water management, applying organic fertilizer, improving disease resistance, paying attention to drainage after rain, so as to avoid damage to roots caused by accumulated water in the field. When the diseased plants are found, they should be pulled out of the field in time, and then the diseased points should be disinfected. In the early stage of disease, 500 times of 50% wettable powder or 5000 times of streptomycin sulfate can be sprayed once a week, depending on the severity of the disease.

2. Downy mildew

Downy mildew is the main disease in lettuce production process, which usually occurs in spring and autumn, and can damage from seedlings to adult plants, and the adult plants are more seriously damaged. The main damage to lettuce leaves, when the disease leaves appear pale yellow spots, in humid environment, the back of the leaves appear frost mold layer, serious will spread to the leaves, to the late stage of the disease, leaves die.

Control methods: reasonable rotation, reduce disease degree, use high ridge or plastic film mulching cultivation, select varieties with strong disease resistance, disinfect seeds before sowing. Strengthen fertilizer and water management, apply organic fertilizer as base fertilizer, apply sufficient base fertilizer, minimize or not topdressing, reasonably plant closely, increase permeability and reduce disease occurrence probability. Discovered diseased plants were pulled out in time and taken out of the field for centralized burning. At the same time, Jinlei and Pulike liquid agents were sprayed for prevention and control.

3. Sclerotium disease

Sclerotinia sclerotiorum mainly damages the stem base of lettuce. Yellow-brown water-stained spots appear at the stem base when the disease occurs. Finally, the disease develops and gradually spreads to the whole stem, causing the phenomenon of rotten leaves and rotten hearts. Finally, the whole plant wilts and dies. At high temperature, flocculent hyphae were also produced at the lesion site, which transformed into black sclerotinia in the later stage.

Control method: clean up the field after harvest, clean up the sick leaves, deeply turn the soil, bury the germs deeply in the soil, spread quicklime, turn the ground, make ridges, water, and finally cover the film tightly, and kill the germs in the soil by using this method. When it occurs, it can be controlled by spraying 40% Sclerotium WP 500 times solution or 45% Tekdo suspension emulsion 800 times solution.

4. Insect pests

Lettuce is a leaf vegetable, plus its leaves are green and tender, not only do we like it, aphids also have a special liking for it, often gather on the leaves, constantly suck the juice of the leaves, so that the mesophyll tissue disappears, leaving only one epidermis, preferably withered and dead.

Control method: aphid outbreak with 10% imidacloprid wettable powder 1500 times solution or yellow board trap.

The above is the lettuce pest control methods, I hope to help you, want to know more about vegetable cultivation knowledge, please pay attention to us.