Alternariosis develops from a fungal mold at a temperature of + 22 ° C and high humidity. The disease is typical for the middle and southern latitudes of our country, and also manifests itself in the Ural region. The fungus is able to overwinter in contaminated land with average negative indicators, but it dies in severe frosts.
The pathogen spreads along the level of the lower leaves, also affecting the stems, shoots and tubers. Gardeners call the disease dry spot due to the appearance of the infection. Early and mid-ripening potato varieties are most often infected.
Unfortunately, I note that there are no hybrids resistant to Alternaria, so it is extremely important to recognize and fight the fungus in time.
In addition, the disease affects not only potato plantings, but also other vegetable crops:
- tomatoes;
- zucchini;
- carrot;
- eggplant;
- onion;
- sunflower;
- pepper.
Weakened bushes are the first to be hit by the fungus, however, completely healthy plants also have a high risk of infection.
Infection and risk factors
Fungal spores spread in the wind and begin to multiply actively when they hit tubers and stems in conditions of comfortable temperature and humidity.
At the same time, there are a number of factors that create a favorable environment for the fungus:
- lack of nutrients and minerals;
- unstable humidity;
- hot weather;
- improper preparatory work;
- stagnation of rain, irrigation or other sedimentary waters;
- low level of plant immunity;
- location of potatoes close to other infected crops (tomatoes and peppers become frequent carriers and distributors of the fungus);
- negative consequences of the action of parasites.
Observation from personal experience: if hot weather in summer is often replaced by heavy rains, then there is a high risk of the spread of the fungus. In this climate, it is necessary to check the bushes more often for infection.
Signs of infection
After a short incubation period, the spores of the fungus begin to actively spread and infect potatoes.
From the external symptoms, I can distinguish the following signs:
- the appearance of small dark spots on the lower leaves - over time, they grow and turn black;
- weakening and falling of leaves;
- the appearance of dark spotting on tubers;
- the formation of putrefactive areas in the pulp of root crops;
- the appearance of dark lines on the stems and cuttings.
Fight Options
Specialized preparations effectively cope with alternariosis, the solution of which is used to treat the affected bushes:
- Kuproksat;
- Profit;
- Utan;
- Metaxyl;
- Thanos;
- Oksikhom;
- Albite;
- Pencozeb;
- Novosri.
I definitely recommend that you strictly follow the instructions for use of each drug, so as not to harm the weakened shoots.
Also, copper oxychloride solution showed good therapeutic results.
Antifungal drugs are quite toxic, so I advise you to take all the necessary safety measures very seriously to eliminate the risk of injury.
Often there is an effect of addiction of the pathogen to a particular drug, so I strongly recommend using several agents in turn at once.
As a preventive measure, you should dig deep into the area for planting, adhere to the correct crop rotation, use only high-quality seed and carry out periodic spraying with special drugs.
How do you deal with potato fungus?
Read also: We grow potatoes under straw or hay. Process Features
Another related article: Blueberry potatoes: description of the variety, taste, features of cultivation and care
Friends, do not forget to subscribe to the channel and leave a LIKE if the article is useful!
#potato#potato diseases#garden