Biological control of Phytophthora infestans in potatoes

Abstract

Abstract. Potato late blight caused by Phytophthora infestans is a serious disease of potatoes (Solanum tuberosum) and is a common disease in all potato growing regions of Russia. However, successful cultivation of potatoes requires a high level of knowledge and skills from the agronomist. To avoid losses in yield and quality, an average of seven to eight fungicide treatments against this disease are carried out annually. It costs time and money and pollutes the environment. In traditional cultivation, the disease is controlled with the costly application of chemical pesticides. Treatment of tubers with chemicals is effective in reducing tuber-borne infections, but the use of chemicals is dangerous, harmful to beneficial microorganisms, and expensive. In addition, infected tubers should not be stored as they will rot. If the infection is not dealt with, there is a risk of complete loss of the crop. A lot of money has been invested in research and breeding, however, late blight is still the most important disease in potato cultivation. If in some years or regions the disease manifests itself slowly and not very aggressively, in other regions it causes significant crop losses. On the other hand, in agriculture, it is controlled with a comprehensive control strategy, which also includes a wide range of cultural and preventive measures, such as the biological method. Among the various methods in the protection of plants from diseases, the biological method is currently an important share. The mentioned biological method among the means uses special microorganisms, which are characterized by a strong antagonistic reaction in relation to specific pathogens. Scientific novelty lies in the fact that biological preparations showed excellent field performance against late blight in the foothill zone of North Ossetia-Alania. The aim of the study was to test whether the biological defense method against Phytophthora infestans is suitable in the Piedmont zone of the Republic RNO-Alania. Researches were carried out according to the methods accepted in potato breeding according to the recommendations of the All-Russian Institute of Plant Industry, VIR and VIZR. According to the results obtained in field experiments show that in all years of research biopreparations significantly reduced infestation of tubers of phytophthora infestans. Biopreparation “BisolbiSan”, which was used for tubers dressing and spraying of plants four times during the growing season, showed the best protective effect against phytophthora infestans in comparison with other preparations.