How to control bacterial angular leaf spot of cucumber in summer

Cucumber is a vegetable that people love to eat in summer, and this vegetable can be eaten almost all year round. Cucumber is also the crop that farmers grow most in their fields; cucumber vines can generally be seen in rural areas. However, cucumber is also a vegetable with relatively many pests and diseases when grown, especially in summer when the diseases are quite serious, which leaves many growers completely confused. So below, Shuaishuai will tell everyone how to control bacterial angular leaf spot of cucumber!

I. Conditions for disease onset

1. The pathogen of this disease likes to attach to cucumber seeds. This pathogen does not move around, but overwinters in the residues of diseased plants, and then wakes up the next year to infect cucumbers. Moreover, its lifespan is very long, generally able to live for as long as two years. Its main modes of transmission are rain transmission and irrigation water transmission. After being absorbed by the plant with water, or directly entering the interior of the plant through stomata or wounds on the plant, it causes disease. It can spread a second time, and after one rain it can repeatedly infect again.

2. When cucumbers are grown in greenhouses, the air humidity inside is generally relatively high, which easily causes the pathogen to become purulent, and the diseased pus easily infects other parts and plants. At the same time, the resistance of cucumbers will decline. If everyone does not pay attention to this disease, it can easily spread and infect repeatedly.

3. The optimal temperature for disease onset is between 24-28 degrees, with a maximum of 39 degrees and a minimum of 4 degrees. This pathogen is not tolerant of high temperatures. If the temperature reaches as high as fifty degrees, it will die within ten minutes. The optimal humidity is around 80 percent. If there is a lot of water on the leaves, the disease incidence is high. Therefore, from this it can be seen that this disease is a type of disease of high temperature and high humidity.

II. Control methods

1. Because in summer the temperature can often remain above thirty degrees, this is the period of high incidence of bacterial angular leaf spot of cucumber. This disease mainly harms the leaves and stems. The symptoms of this disease are very similar to the symptoms of cucumber downy mildew, so choosing control measures will bring certain difficulties. When judging, everyone must observe carefully whether it is downy mildew or angular leaf spot. Otherwise, if the wrong method is used and the wrong pesticide is sprayed, it will certainly cause death and economic losses. Everyone should take measures as early as possible.

2. When selecting seedlings, try to choose seedlings with strong disease resistance. This is something that can be done when selecting seeds.

3. When collecting seeds, choose healthy varieties with no disease. Only in this way will the seeds cultivated be excellent.

4. Before sowing, the seeds need to first be placed in a 70-degree constant-temperature cabinet for three days for sterilization, then soaked in fifty-degree warm water, and finally taken out, dried and sown.

5. Heavily diseased fields should undergo crop rotation for more than 2 years. During the growth period, diseased leaves and diseased plants should be promptly cleaned up to avoid secondary infection. The cleaned materials can be directly deep-buried or burned.

The above are the control methods for bacterial angular leaf spot of cucumber in summer. Have you all learned them? In normal times, everyone should observe more and try to take corresponding measures promptly at the early stage of disease onset. In normal times, prevention and control management should be strengthened. Only in this way can infection be avoided.