Assessment of The Impact of Biological Products on the Quality of Potato Tubers

The aim of the study was to assess the effect of beneficial microorganisms introduced into the soil on selected indicators of the quality of edible potato tubers. The study evaluated an early, unpretentious, drought-resistant, frost-resistant and stress-resistant potato variety of the Russian selection "Udacha". When growing potatoes, biological products "Organic", "Protection of roots" and "Crop rotation" were used, which include bacteria and fungi in its composition. The experiment provided for 4 options: 1) Control, 2) "Organic", 3) "Protection of roots", 4) "Crop rotation". Biological products "Organic" and "Protection of roots" were applied when planting potatoes, and the biological product "Crop rotation" was applied two weeks before planting. In the grown potato tubers, the starch composition was determined using the polarimetric method, the vitamin C composition was determined using the visual titration method, the polyphenol composition was determined using the spectrophotometric method applying Folin's reagent, the antioxidant activity was determined using potassium permanganate titration, and the nitrate composition was determined using an ion-selective electrode on an ion meter. The results of the research showed that in potato tubers the starch composition was the lowest in the control variant (14.9%), and the highest in the variant with the biological product “Crop Rotation” (17.8%); the composition of vitamin C was the lowest in the control variant (18.9 mg/100 g), and it was the highest in the variant with the biological product “Crop Rotation” (25.3 mg/100 g); the composition of polyphenols (in mg-eq of gallic acid per g of dry weight) was the highest in the variant with the biological product “Organic” (4.1), and the lowest in the control variant (3.0); antioxidant activity (in mg-eq of gallic acid per g of dry weight) was the lowest in the control variant (6.5), and it was the highest in the variants with biological products "Organic" and "Crop rotation" (8.4); the composition of nitrates decreased in all experimental variants in comparison with the control variant. The application of beneficial bacteria and fungi into the soil greatly contributed to the improvement of the quality indicators of grown potato tubers.