What are the main points of prevention and control of cucumber blight?

Cucumber is planted in many places in our country, once it is attacked by diseases in the specific planting process, growers will certainly face the problems of yield reduction, quality reduction and so on. What are the main points of prevention and control of cucumber blight?

Symptoms of cucumber blight

The disease can occur from seedling stage to adult stage, and protected cultivation mainly harms the base of stem, leaf and fruit. The disease of the seedlings began at the tender tip, showing a water-stained dark green round spot at the beginning, and gradually turned reddish brown in the middle of the later stage, and the seedlings withered and died. At the adult stage, it mainly harms the base of the stem, the node of the tender stem, the spindle-shaped and oval dark green watery spot, the post-disease part constricts obviously, becomes dark brown and rotten when wet, and the edge of the spot is dark green when dry, brown, dry and fragile. The vine leaves withered above the damaged parts, and the leaves were often damaged in several places on a vine stem, and the whole leaves rotted when the humidity was high. Fruit damage, mostly occurred in the flower pedicel, the initial appearance of dark green round, near-round water-stained sunken spots, can be extended to the whole fruit, wet when the disease surface has white mildew, rapid decay, emitting fishy smell.

Cucumber blight is a soil-borne disease. The pathogen overwinters with ascomycetes, mycelia, chlamydospores and oospores in soil and soil miscellaneous fertilizer, and spreads mainly by means of running water, irrigation water and Rain Water splash, and can also be transmitted by fertilization. Invade from the wound and natural orifice to cause the disease. Sporangia and zoospores were produced in the disease department after the disease, and the disease spread rapidly with the help of airflow and Rain Water sputtering transmission.

II. Prevention and control of cucumber blight

1. Select disease-resistant varieties

Grafted seedlings, strong seedling planting, pay attention to rotation with non-melon crops, increase the application of biological bacteria organic fertilizer, phosphorus and potassium fertilizer and medium and trace element fertilizer, reduce the use of nitrogen fertilizer, prevent the excessive growth of melon seedlings, adjust the relationship between vegetative growth and reproductive growth, and maintain robust growth. improve the disease resistance of the plant itself.

2. Adjust the ecological environment and pay attention to reducing the microclimate air humidity in the field.

Field cultivation should carry out north-south direction, appropriately increase row spacing, improve ventilation conditions, reduce air humidity, facility cultivation, high temperature management (32-35 ℃) in daytime, increase ventilation at night, implement low-temperature management (10-16 ℃), reduce indoor air humidity, create an environmental condition unsuitable for epidemic infection and development, and control the occurrence of diseases.

3. Remove the source of the disease in time

All kinds of sick and disabled bodies should be removed in time, buried deeply on the spot, and littering everywhere is strictly forbidden to spread germs and spread diseases.

4. Chemical control

It is necessary to use drugs scientifically, and under the guidance of the principle of "prevention first, comprehensive prevention and control", field cultivation should strive to use medicine before every rainfall, and in case of continuous rainy weather, it is necessary to seize the interval between rainfall and spray pesticides to protect it. In protected cultivation, the medicine should be used before each irrigation, and the melon seedlings should be protected before watering.