Tomato cercosporosis: symptoms, causes, treatment
Infections pathogens that cause pathogens cause great harm to tomato plantings. With steady rainy weather in the first half of summer, dark gray round spots appear on the leaves of tomatoes, surrounded by brown edging. The disease belongs to the fungal and is called kerkosporoz tomatoes.
The reasons
The reasons for the development of a pathogen can be the following factors:
- planting tomatoes in heavy clay soil;
- high humidity above 70%, which lasts more than 30 days;
- planting tomatoes next to infected plants that are susceptible to fungi: potatoes, sorrel, beans;
- an infected tool used in working with plants;
- rainy and hot July-August month.
Symptoms
Damage to the pathogen begins in the upper part of the leaves and manifests itself as:
- light gray fluffy plaque on the upper part of the foliage formed by the needle-like conidia of the fungus;
- the appearance on the leaves of small spots of gray-brown color of 3-5 mm;
- covering the whole part of the leaves and their fall.
Treatment
At the first signs of infection with a pathogenic infection, it is necessary to treat tomatoes with systemic fungicides with benzimidazoles in order to neutralize the pathogens at the initial stage:
- Tango Star;
- Thiophene;
- Difenoconazole;
- Topaz;
- Ordan;
- Kurzat;
- Chorus;
- Amistar Extra;
- Quadris;
- Ridomil Gold.
Prevention
The organization of preventive measures will increase the immunity of tomatoes, prevent re-infection with spores. They include:
- compliance with good crop rotation, in which good predecessors of tomatoes will be: a layer of perennial grasses, legumes, onions, cucumbers;
- the cultivation of disease-resistant varieties of tomatoes;
- ensuring good air circulation between plants;
- selection of a site for planting tomato seedlings next to bitter pepper, garlic, onions;
- processing of seed material and seedlings with biological fungicides: Gamair, Fundazol, Fitosporin;
- introduction into the soil before planting tomatoes phosphorus and potassium in 25 g of each element per square meter.
Biological preparations Gamair, Fitosporin are not compatible with many fungicides and mineral fertilizers. Therefore, the processing of biological means to carry out without the addition of chemicals.
Resistant varieties
It is possible to avoid the treatment of cercosporosis by picking up resistant varieties for planting and hybrids as:
- Attiya F1;
- Afen F1;
- Bull heart red;
- Don Jose F1;
- F1 crystal;
- Lilos F1;
- Liang;
- Katya;
- Portugos F1;
- President F1;
- Tolstoy F1;
- Florentine F1;
- Esmira F1.
Compliance with the simple rules of cultivation and timely spraying of tomatoes from the pathogen in the early stages of the disease, will not only preserve healthy fruit. But also to increase yields.