Influence of Plant Protection Products on the Enzymatic Activity of Calcic Chernozem

The studies were carried out in Rostov region in order to assess the pesticides treatments effect on the enzymatic activity of calcic chernozem. The activities of catalase, invertase, phosphatase and urease were studied. The cultivated crop is chickpeas Donplaza variety. The experiment scheme included 8 variants: control; two variants of chemical plant protection, a biological plant protection system on unfertilized and fertilized backgrounds. The studied chernozem is classified as moderately enriched and rich in catalase, moderately enriched in invertase and phosphatase, and poor in urease. Catalase activity in the arable horizon varied in all variants within the range of 9.6–12.3 ml O2/1 g/1 min, invertase activity – 30.4–36.8 mg glucose/1 g/24 h, phosphatase activity – 2.3–4.3 mg P2O5/10 g /1 h, and urease activity–4.5–8.1 mg N-NH3/10 g/24 h. The treatment of soil and plants with chemical protection agents has a different effect on various enzymes, reducing the activity of catalase, invertase and stimulating the phosphatase activity. The treatment with biological plant protection agents led to stimulation of catalase activity. The invertase and urease activities were inhibited and the phosphatase activity remained at the same level.