Introduction to the symptoms and control techniques of tomato powdery mildew

Tomato is a common vegetable, which can be eaten raw or cooked, and can be processed into ketchup, juice and other food. Tomatoes are planted in all parts of our country, like to grow in warm places, the requirements for the soil is not very strict. However, tomato powdery mildew is easy to occur if it is mismanaged, so what are the symptoms of this disease? What are the main points of prevention and control techniques?

Symptoms of tomato powdery mildew

Once the tomato is attacked by powdery mildew, if it is not treated in time, the yield will be reduced and the fruit quality will be poor. Because tomato powdery mildew is mainly harmful to tomato leaves, petioles, rhizomes and fruits. There will be a white powder in the early stage of the disease. in fact, the hyphae and conidia of powdery mildew will not be many at first, only sparse white spots, and will slowly thicken with the disease in the home. In addition, there will be yellow-green spots on the edge, which will lead to the death of the whole tomato plant if not treated at this time, that is to say, "there is no harvest".

Tomato powdery mildew is easy to appear in a relatively dry environment, and the main pathogen is in the north. Tomato powdery mildew will spread and spread with the airflow, infect the newly growing leaves, and then continue to infect through the airstream. So prevention in advance is very necessary, let's take a look at the specific prevention and control methods.

2. Technical points for control of tomato powdery mildew.

1. Select tomato varieties with strong disease resistance, and pay attention to the humidity management in tomato planting shed, because drying is one of the causes of the disease. After tomato harvest, it is necessary to clean up the remains of tomato disease in time and reduce the source of the disease during the overwintering, which is also one of the effective ways to curb the discovery of the disease.

2. In the early stage of tomato powdery mildew, and when it is not very serious, smoke method or dust method can be used for disinfection. Spray some powder powder in the evening, the one-time dose should be strictly in accordance with the instructions, no more than 2 jin per mu. If it is the choice of smoke disinfection, it should be lit with a dark fire for one night, otherwise it is difficult to achieve the effect.

3. In the process of planting tomato, we should strictly control the planting density, fertilization method, air humidity, watering method and so on. In order to keep the dry environment in the tomato greenhouse, we only need to maintain the appropriate humidity.

4. When the disease is more serious, it has to be treated with professional medicine. be sure to go to the pesticide market to ask how to use it, and you must use it in strict accordance with the instructions. Spray on the back of the leaves as far as possible, at intervals of one week at a time, and pay attention to the alternate use of drugs to avoid drug resistance.

Through the above introduction, I believe you have a certain understanding of tomato powdery mildew. I hope it will be helpful to you.