FIELD: biotechnology.SUBSTANCE: invention is a method for the preparation of microtubers of potatoes in vitro, including propagation of sample plants and planting single-nodal cuttings on an agarized nutrient medium containing macro- and microelements and vitamins based on the nutrient Murashige and Skoog medium, Fe-chelate, agar-agar, sucrose. According to the invention, when the plant reaches a height of 5 to 6 cm, to the culture vessel in the aseptic conditions of the laminar box agarized nutrient medium cooled to 30 °C is added containing macro- and microelements and vitamins based on the nutrient medium Murashige and Skoog, Fe-chelate, agar-agar, sucrose with reduced to 220 mg/l concentration of NHNOand increased to 80 g/l sucrose concentration without any phytohormones, followed by transfer of plants to the conditions of complete darkness at a temperature of 21–25 °C for 45–60 days. At the end of this period, 98 % of the plants form 1-2 microtubers per 1 shoot in test tubes and 2-3 tubers per 1
