This study is devoted to assessing the effect of Biostim Universal (growth regulator) and BOMU (micronutrient) preparations on the chlorophyll content in leaves, photosynthetic activity and yield of potato varieties Farn of local breeding and Nevsky. The experiments were carried out in the foothill zone of North Ossetia-Alania on leached chernozems of the experimental site of the Research Institute of Agricultural Sciences VNC RAS. The content of photosynthetic pigments in potato leaves was determined by spectrophotometric method at wavelengths of 662, 644 and 440 nm. The positive effect of the drugs on the chlorophyll content has been revealed. The chlorophyll a content in the experimental variants of both varieties is significantly higher than in the control variants, respectively, for the Farn variety – by 4.2, 11.3 and 21.2% and for the Nevsky variety – by 0.7, 16.4 and 25.3%. The same pattern applies to the content of chlorophyll b. The complex use of biologics increased the NPF by 19.8% compared to the control for the Farn variety, and by 13.4% for the Nevsky variety, which affected the yield and quality of potatoes. The biologics used are arranged according to the yield and quality of potato tubers, as follows: Biostim Universal at a dose of 0.5 l/ ha + micronutrient Bomu at a dose of 0.35 kg/ha (option IV), Bomu (option III), Biostim Universal (option II) with yields according to the Farn variety 28.9; 27.4 and 26.9 t/ha (HCP05=2.3t/ha), starch yield – 3.9; 3.7 and 3.4t/ha (HCP05=0.2t/ha), Nevsky grade–27.1; 26.4 and 25.8t/ha (HCP05=2.5t/ha), 3.4; 3.4 and 3.2t/ha (HCP05=0.1t/ha), respectively. The use of biologics and micro-fertilizers causes a reduction in the cost of the Farn grade by 88.4; 71.7 and 103.1 rubles and an increase in profitability by 14.9; 16.8 and 22.4 rubles per 1 ton for the experimental options compared to the control. Net income is 65.1, 68.4 and 70.5 thousand rubles against 58.6 thousand rubles in control.
Larisa Ikoeva (2025) studied this question.