In July, the chance of defeating potatoes with various infections increases. First of all, late blight and alternariosis, which can negatively affect the formation of new tubers.
We ask for clarification at the Scientific and Practical Center for Potato and Horticulture of the NAS of Belarus. Associate Professor, Candidate of Agricultural Sciences, Head of the Department of Immunity and Potato Protection, Ivan Busko, clarifies that some varieties really suffered from changes in the weather, but most of them are affected by common scab: - The fact is that during flowering, when new tubers form, the culture needs moisture, and since there was a drought in June, favorable conditions developed for the spread of infection. The scab hit not only the skin, as it mostly happens, but also the flesh, and this, in turn, impedes the development of culture.
In general, the appearance of the same scab in the garden depends on several factors, primarily on the quality of the soil. As a rule, she loves light sandy and sandy loamy, as well as strongly calcareous, as lime helps spread fungi. Secondly, fertilizers. For example, if you use unripened manure, it will only increase the development of infection. Thirdly, weather conditions. If there is a high temperature during flowering, there is not enough moisture, then there will be very few new tubers. Therefore, during a drought, you need to water the potatoes in order to minimize the risk of subsequent loss of the future crop.
If we talk about late blight, then for its spread at the moment almost the most favorable conditions have developed: air temperature, not exceeding plus 20 degrees, a lot of moisture. But for alternariosis, a completely different weather is needed: heat at 30 degrees, drought, lack of nitrogen and potassium in the soil, as well as an excess of phosphorus. True, according to Ivan Busko, potatoes at the time of flowering need protection constantly, and regardless of external factors:
- Even if the soils are suitable and the fertilizers are selected correctly, and the weather is favorable, treatment with chemicals is still necessary, otherwise there is a high probability of crop loss. Late blight, for example, is almost impossible to cure, but this is such a disease that, having struck one ovary, it can easily spread to the entire field if preventive measures are not taken in advance.
According to experts, the level of protection of potatoes from late blight is determined by the number of treatments. When there are good conditions for the development of infection, you need to do this at least five to six times. Moreover, it is important to start spraying in a timely manner, otherwise the effectiveness of the drugs will decrease by 50-70 percent. Therefore, the future potato harvest depends on the attentiveness and quick action of our farmers.
Source: Selskaya Gazeta
Read more: https://agronews.com/by/ru/news/agrosfera/2019-07-18/38089