The research purpose is to compare the no-till Triticum aestivum L. cultivation technology with a traditional cultivation system and their influence on soil moisture, the number of weeds, soil density, aggregate composition and a structure coefficient. The studies were conducted in 2015–2018 in the Steppe Crimea. Crop rotations consist of the same set of plants with the exception of the first link: under the traditional system: black fallow – winter wheat — oil flax — winter barley — grain sorghum; under the no-till system, pea was sowed at the first field. The experiments were conducted in accordance with generally accepted methods of field experiments in agriculture and crop production. By the time of sowing, a larger amount of moisture accumulated in the black fallow compared to the field of peas. It was 0–10; 0–20; 0–100 cm for 1.9; 5.5 and 20.6 mm, respectively. In spring, the amount of productive moisture was at the same level. Under the traditional system, it was 104; under the direct sowing, it was 102 mm. Using the direct sowing technology, the absence of mechanical soil loosening had no effect on the density parameter in comparison with the traditional farming system: density was normal, regardless of the farming system: 1.13 g/cm3 under the traditional system, and 1.19 g/cm3 under the direct sowing system; in the 10-30 cm layer, it was 1.45 g/cm3; in general, in the 0–30 cm layer, the difference was not significant (1.34 and 1.36 g/cm3). The species composition of weeds did not change. The direct sowing technology used for untreated soil had a positive effect on the soil structure. By the third year of research, the coefficient of structure was 2.94 (under the traditional system), and 4.05 (under the direct sowing system).

The goal of the research is to study the effect of Pisum sativum L. seeds treatment before sowing with a complex of microbiological preparation, in comparison with a chemical treatment, on the parameters of plants growth, product quality, and yield, against the background of the system of agriculture without soil tillage. The research was conducted in 2016-2018 in the zone of Central Steppe of Crimea. Trial establishment and researches were carried out in accordance with the generally common methods of field experiments in land husbandry and plant growing. In 2016, the symbiosis of Pisum sativum L plants and the microbial community had a significant impact on the number of beans per plant: the control was 7.6 pieces on 1 plant, and under the influence of complex microbial preparation is 8.6 units per 1 plant (LSD05 – 0,92). The weight of grain from 1 plant was significantly higher by 0.5 g on the variant with inoculation. In 2017 on plant height there is a slight increase in growth when treated with the preparation by 4.4 cm (LSD05 – 5,03). The same thing happens with the number of beans of 8.2 and 8.6 units on the same plant that shows at LSD05 – 1.59, the accuracy increase of this parameter at 0.4 units per plant in the variant with inoculation. Severe weather conditions during the vegetation of Pisum sativum L. in 2018 contributed to the fact that the microbial preparation studied by us practically did not affect the studied indicators of growth and productivity.

Agricultural technologies aimed at reducing the tillage can be adopted as safer farming methods to preserve and improve the diversity of soil microbial communities. The area under the promising resource-saving no-till system (direct sowing) is increase in the conditions of the Steppe annually. The use of herbicides in such a farming system causes a negative effect on the soil biocenosis. But the introduction of agronomically useful microorganisms into the rhizosphere are increasing the resistance of plants against stress factors, their yields and product quality, and preserving soil fertility. The objective of this research was to assess the state of microbiocenosis of southern chernozem under the influence of no-till system and a complex of microbial preparations. The influence of direct sowing and microbial preparations on the state of microbocenosis of southern chernozem was established. The number of cellulolytic microorganisms increased under the influence of farming systems in comparison with the virgin soil. The use of microbial preparations contributed to an increase in the number of microorganisms of ecological and trophic groups and the representation of the majority of phyla, which also depended on the system of agriculture. A decrease in the representation of Acidobacteria and Verrucomicrobia and an increase in Firmicutes and Proteobacteria were observed in comparison with virgin soil.

The taxonomic structure of the microbiome of southern chernozem compared to virgin soil was studied in the stationary experiment on the use of microbial preparations in the conditions of traditional for the steppe part of the Crimea and each culture of the five-field crop rotation of the farming system and no-till. Among 823 genera it was revealed 7 dominant ones: Candidatus Nitrososphaera, Rubrobacter, Flavisolibacter, Segetibacter, Bacillus, Balneimonas, Skermanella. The low level of cellulose-decomposing bacteria of the genus Cellulomonas was remarked in southern chernozem. The highest proportion of the representatives of this genus was observed in virgin soil (0.55 %), while the farming systems contributed to its decline in 1.3-1.6 times. Microorganisms of the genera Erwinia and Xanthomonas with phytopathogenic properties were found with a minimum proportion in communities from 0.003 % to 0.014 % and 0 – 0.005%, respectively. The complex metagenomic analysis of the taxonomic structure of the soil microbiome allowed us to establish that the use of microbial preparations reduces the negative impact of the no-till farming system on the microbiocenosis of southern chernozem and improves its environmental feasibility in the Crimean steppe.

A research was carried out to evaluate the effect of winter wheat plant residues on the content of productive moisture and on the soil structure and physical state under different tillage in the Steppe Crimea. A reliable moisture accumulation (115 mm in a meter soil layer) was revealed at the experimental plots where no-till was applied. The quality of soil structure under both farming systems (no-till and traditional one) can be assessed as an excellent one. Values are in the range of 78.0-81.3%. The coefficient of soil structure is in optimal values and averages 4.3.