APPLICATION OF WATER-SOLUBLE FERTILIZERS AND GROWTH REGULATORS IN THE CULTIVATION OF PLAMYA POTATO MICROPLANTS IN PROTECTED GROUND

The article presents data from a pilot experiment conductide in 2024-2025 in summer greenhouses at the Kostroma Research Agriculture Institute – Branch of Russian Potato Research Centre. The aim of the study was to investigate the effect of water-soluble fertilizers and growth regulators on the formation of productivity, structure, and quality of mini-tubers of the 'Plamya' potato variety under protected ground conditions. The studied factors were: a line of water-soluble fertilizers with microelements – Aquarin 5, Aquarin 13, Aquarin 12; and Aquarins combined with growth regulators: 5 Plus, 13 Plus, 12 Plus, and DA-6. On average over the years of research, all experimental variants, except for the combined top dressing (variant 3: root application of Aquarins 5, 3,12 and foliar application of Aquarins 5 Plus, 13 Plus, 12 Plus), provided a significant increase in average tuber weight compared to the control. In variant 4(root application of Aquarins 5,13,12 and foliar application of the growth regulator DA-6), a substantial gain of 14,7 g or 62,8 % compared to the control variant was obtained. When using Aquarins (5,13,12) as both root and foliar applications in their pure form (variant 2), as well as the combined feeding (root with standard Aquarins and foliar with Aquarins Plus), a significantly higher number of tubers per plant was recorded 7,0 pcs. and 7,2 pcs., respectively. The highest number of tubers with a diameter of 25–60 mm per square meter was obtained by applying Aquarins 5,13,12 via root and foliar dressings in their pure form (variant 2), which was 35,6 pcs./m² or 58,3 % higher than in the control. The highest productivity, expressed in kg/m², was achieved by applying Aquarins 5,13,12 as a root dressing and the growth regulator DA-6 as a foliar spray (variant 4), which was 1,58 kg/m² or 90,3 % higher than in the control variant. These data are statistically reliable.