Evaluation of the Effect of Biostimulants Based on Beneficial Microorganisms on the Amino Acid and Elemental Composition of Carrot Roots

The production of products with the optimal content of vegetable protein and the necessary macro- and microelements is an important task for agriculture. Biostimulants containing the bacteria Azotobacter chroococcum, Bacillus subtilis, Bacillus megaterium, and the fungus Trichoderma harzianum were used to grow carrots on soddy-podzolic soil in the Moscow Region. The compound of amino acids in the grown root crops was determined on the Kapel-105 M analyzer, as well as the elemental composition using inductively coupled plasma mass spectrometry on a Nexion 300 D device (Perkin Elmer, USA). The determination of 17 amino acids in carrot roots showed that the amount of essential amino acids in the variant with biostimulants was 46.3% higher than in the control variant, and amounted to 5.12 g/kg DM, while in the control - 3.50 g/kg DM. At the same time, the compound of 11 amino acids increased (g/kg of DM): aspartic acid (from 3.73 to 4.12), serine (from 0.93 to 1.08), proline (from 0.03 to 0.04), valine (from 0.003 to 0.046), isoleucine (from 0.02 to 0.67), leucine (from 0.75 to 0.82), tyrosine (from 0.55 to 0.64), phenylalanine (from 0.62 to 0.72), histidine (from 0.42 to 0.52), lysine (from 0.02 to 0.69), arginine (from 0.05 to 1.00). The treatment carrots showed the increased level of vital macroelements (phosphorus, calcium, magnesium) and microelements (iron, zinc, silicon, manganese, copper, chromium, nickel, vanadium, iodine, cobalt).