The effectiveness of humic acid salts and chelated forms of microfertilizers when cultivating potatoes on irrigated chestnut soils of the Transvolga region

In 2019–2022 field experiments with fertilizers based on humic acids were carried out on irrigated chestnut soils in the Saratov Transvolga region. The object of the research was the released variety of potato Silvana. The comparative evaluation of products containing the alkaline extraction of humic and fulvic acids (potassium humate) and chelated forms of microfertilizers (Reasil® micro Hydro Mix) was given. On average within 4 years of experiments the extra yield due to three-time application of potassium humate was 2.82 t/ha compared to the control. Three-time spraying of potato crop with the solution of Reasil® micro Hydro Mix increased the yield by 3.48 t/ha. Considering the statistically inaccurate difference between these two groups (0.66 t/ha), the equivalent influence can be established. The maximum yield of commercial potato tubers of Silvana variety was obtained with the combined application of potassium humate and Reasil® Forte Carb-N-Humic, that is 25.86 t/ha. Fertilizers based on humic acids increased the yield of starch by 475-1076 kg/ha.