What medicine is effective for growing cucumbers with powdery mildew?

Powdery mildew on cucumbers grown in the open air is generally more common in dry weather after rain. It is recommended to use 25 ethylpyridinol, 25 ethylpyridinol sulfonate, 25 teconazole, 30 ethylpyridinol, 10 fluorosilazole, 25 hexaconazole, etc. When spraying, you can also combine it with 32-acetozolinone or 50-chlorobromoisocyanuric acid, which has a significant synergistic effect. Powdery mildew spores will die quickly and fade away quickly.

What causes cucumber powdery mildew?

Powdery mildew on cucumbers grown in the open air is generally more common in dry weather after rain, because the onset of powdery mildew requires both temperature and humidity. .

Powdery mildew bacteria can develop in the temperature range of 15-30 degrees Celsius, but are most suitable for onset at 20-25 degrees Celsius.

Different from the conditions for the onset of other fungal diseases, powdery mildew is a very drought-tolerant pathogen. It has less stringent requirements for air humidity and can develop when the humidity is around 40-90.

Therefore, cucumbers grown in the open air will experience drought after rainfall in summer and autumn. Because the air humidity is suitable and the temperature drops, the conditions are suitable for the occurrence of powdery mildew.

In addition, if powdery mildew has already occurred in the field, the pathogen can also be spread to other leaves or plants through airflow, raindrops, and water splashes.

1. If cucumbers are planted with high density and poor ventilation and light transmission conditions, the disease will become more severe.

2. If nitrogen fertilizer is applied too much, the stems and leaves will grow too fast, the cell walls of the leaves will become thinner, and the resistance will be reduced, making it easier for the disease to develop.

3. In heavily cropped plots, too many diseased residues remain, which can easily lead to crop disease.

4. Insufficient application of potassium fertilizer, organic fertilizer and calcium fertilizer will also affect the resistance of cucumber plants, making them susceptible to disease

5. Suitable temperature, continuous alternation of drought and humidity, and insufficient light It is easy to get sick under certain circumstances, especially when it is dry for a long time after continuous rain. Too much rain will inhibit the development of powdery mildew.

How to prevent and control cucumber powdery mildew

1. Pay attention to field inspections. When the disease occurs in the early stage, remove the diseased leaves promptly and take them out of the greenhouse to eliminate the source of infection and prevent the bacteria from infecting other plants. of plants.

2. The reason why too much rain will inhibit the development of powdery mildew is that when powdery mildew spores encounter water, they easily absorb water and rupture, which is detrimental to spore germination. Therefore, you can take advantage of this. During prevention and treatment, first wash away the white powder with clean water, and then apply the medicine again.

3. Pay attention to the supplement of phosphorus and potassium fertilizers, calcium fertilizers, and organic fertilizers, which can also improve the resistance of cucumber plants and reduce the occurrence of powdery mildew.

4. In the season when powdery mildew often occurs, use protective fungicides in advance for prevention; use therapeutic fungicides for sterilization treatment in the early stages of powdery mildew.

Warm reminder: Do not ignore it in the early stages of the disease and only treat it with medication when the disease is serious. Not to mention the increased cost of medication, it will already cause losses to the crops.

What medicine is effective against cucumber powdery mildew?

It is recommended to use 32.5 benzyl·azoxystrobin, 25pyraclostrobin, 1.5Sophora flavescens ostulin, 75trichostrobin· Tebuconazole, 42.8 fluorobacteria, trifloxystrobin and other products are available.

Therapeutic fungicides should be used after the onset of powdery mildew:

It is recommended to use 25 ethylpyrrolidone, 25 ethylpyridinol sulfonate, 25 penconazole, and 30 pyrizofen·pyrizofen Phenol, 10-fluorosilazole, 25-hexazole alcohol, etc. can be used.

When spraying, you can also mix it with 32 acetone acetonitrile or 50 chlorobromoisocyanuric acid, which has a significant synergistic effect. Powdery mildew spores die quickly and fade away quickly.

When spraying, the spray should be applied evenly and thoroughly without leaving any dead spots. Pay attention to spraying on the ground as well, because white powdery spores washed down by water or chemical solution will remain on the ground.