Powdery mildew is dangerous for currants due to the speed of its spread and the ability to cause great damage to the crop.
The disease is caused by a pathogenic fungus. Symptoms appear as a white coating on the berries and shoot tips.
At a later stage, the stems begin to dry out, the leaves curl and turn pale.
Fungicides and folk remedies are used to combat the disease.
Since the fungus can overwinter in the soil, treatment against powdery mildew begins in early spring after the snow melts.
The bushes and the ground beneath them are sprayed with a 1% solution of copper sulfate. Of the chemical fungicides, the most effective are (dosage per 10 liters of water):
"Skor" - 2 ml;
"HOM" - 40 g;
“Fundazol” – 1 ml;
"Topaz" 2 ml.
Treatment is carried out at the first signs of infection and then 1-2 more times.
The interval between sprayings is indicated in the instructions for each preparation.
During the fruiting period, it is better to avoid chemicals and use compositions prepared according to folk recipes.
The following help to cope with fungus:
- whey solution (1 l per 10 l of water) – spray three times with an interval of 3 days;
a composition based on soda and liquid soap (2 tablespoons of each per 10 liters of water) - carry out 2 treatments at intervals of a week;
- ash solution (300 g per 5 l of hot water) - leave for 8-10 hours, then strain and use for spraying.
If it rains soon after applying the composition, the treatment is repeated.
Prevention should not be neglected either. Bushes should be thinned out in a timely manner. In early spring, currants are doused with boiling water, this reduces the risk of disease by 60-70%.
The soil under the bushes is kept clean and regularly loosened. For prevention, the soil can be treated with a solution of "Fitosporin" several times per season.