COMPREHENSIVE ASSESSMENT OF SOIL CONDITION AFTER VARIOUS CROPS

The paper presents an assessment of the state of the soil after harvesting crops (cereals, legumes, technical, perennial grasses) on the experimental fields of the Agrobiotechnopark of Kazan State Agrarian University in industrial crops. The studies were carried out in 2022, which was characterized by significant differences in moisture conditions during the growing season of plants (the first half of the growing season is wet, the second half is dry). All plots were located on highly cultivated, gray forest, medium loamy soil. A comprehensive assessment of soils was carried out using the methods of agrophysical studies of soils and methods of soil biology. To assess the state of soil biology, the number of microorganisms, Protozoa and nematodes was taken into account. Simultaneously, the phytotoxicity of soils for model plants was determined. Analysis of the accumulation of available water in the soil and the share of agronomically valuable aggregates showed that the maximum values were after mustard. After this crop, there was a decrease in the density of soil composition. The deterioration of the agrophysical properties of the soil was noted after spring crops. A pronounced phytotoxic effect of soil extracts after spring barley, peas and potatoes was established in relation to lettuce test plants. A similar effect on the wheat test plant was noted after potatoes. Improvement in agrophysical properties, low phytotoxicity and suppression of the development of Fusarium fungi among the studied crops, the advantage was noted for Sarepta mustard. After peas, an increase in the number of Azotobacter bacteria in the soil was noted, and after winter wheat, an increase in the number of ciliates in the soil was noted. The results obtained confirmed the differences in the state of soils after various crops, which must be taken into account when selecting predecessors in crop rotation.