Phytophthora on tomatoes: methods of control and prevention

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

In late summer or early autumn, gardeners often encounter dark spots on tomatoes that gradually spread over the surface. This is the so-called phytophthora on tomatoes. Methods of dealing with it include the use of certain chemicals and folk methods of prevention. Let us consider in detail what this disease is and how to deal with it.

Light blight

Late blight is considered the main disease of tomatoes in film greenhouses and in open ground. Moreover, cultures of late varieties are affected in the soil. This is due to the fact that favorable conditions for the spread of the disease (dew drops that occur when the difference between day and night temperatures) develop in late summer or early autumn.

When spots are found, gardeners immediately guess that they may have late blight on tomatoes. "What to do?" they ask. First you need to find out if this is reallyso, after all, spots can be with other diseases.

Late blight affects fruits, stems and leaves. Brown spots appear on the edges of the leaves, below - a white coating of sporulation. On stems and petioles, spots are elongated, without plaque. Fruits are sometimes covered with hard brown rot. Source of infection - affected plantings

potatoes and oospores, which are stored in the soil on plant residues.

Phytophthora on tomatoes: methods of control, taking into account the rules for growing crops

1. Places for tomatoes need to be constantly changed and do not plant crops near potatoes, as spores remain in the soil for a long time.
2. Tomato seeds are disinfected with potassium permanganate or Vitaros, as they may also contain fungus spores.
3. Potato and tomato leaves are burned or buried deep, as the spores are carried by the wind and remain in the soil until next year.

If you are looking for an answer to the question of how to protect tomatoes from late blight, then know that following these three rules will significantly reduce the risk of disease. Also, you need to plant only strong plants, take care of them in a timely manner and feed them: strong tomatoes are less susceptible to late blight.

In carbonate greenhouses, it is recommended to grow resistant hybrids formed in 1 stem, without thickening, and the greenhouses themselves should be well ventilated. Watering plants during infection is recommended once a week in the absence of precipitation.

Phytophthora on tomatoes: scientific methods of struggle

Nowspecial preparations are available for spraying tomato crops. Popular products based on hay sticks are Fitosporin-M, Baksis, Alirin-B, Gamair. When using them, you must follow the attached instructions. Of the immune stimulants, "Immunocytophyte", "Epin", "Zircon" are well known.

There are broad-spectrum fungicides that protect against complex diseases. These are Quadris, Ridomil Gold, Mefenoxam, Mankozeb, Thanos, Famoxadone, Cymoxanil and others. Copper sulfate is also used, but it is already becoming a thing of the past, and it does not always help.

Remember that this is an insidious disease that can destroy the entire crop - late blight on tomatoes. Control methods may include spraying plants and following simple agricultural practices, such as changing beds, disinfecting seeds, and removing potato and tomato residues. Practice shows that this is enough to prevent the fungus from infecting the culture.