THE INFLUENCE OF DIFFERENT CROP ROTATIONS AND FERTILIZATION SYSTEMS ON CHERNOZEM SOIL BULK DENSITY

The soil health can be deduced by chemical, biological and physical properties. This triad of features influence each other and equally determines soil quality and fertility. The paper includes the study regarding physical state of the chernozem soil characterized by bulk density – soil physical property that estimate soil compaction. The study took place in long-term field experiments of the Selectia Research Institute of Field Crop located in the North part of Moldova. The experimental data were obtained in 2019-2020 agriculture year. The soil bulk density, studied in different crop rotations and fertilization systems, was determined under winter wheat agrocenosis after harvesting in the 0-40 cm soil layer. The researches has shown that chernozem soil bulk density registered more favorable indices in crop rotations that include: perennial legumes and grasses in a mixture or only perennial legumes; less row crops - which means minimizing tillage (mechanic disturbance of soil). Regarding fertilization systems – the soil compaction is lower on the plots with adequate amount of organic fertilizer.

DEVELOPMENT OF LIVESTOCK BASED ON MODERN FEED PRODUCTION

The state of animal husbandry in the country, directions of intensification of the industry, factors that restrain the growth of economic efficiency of animal husbandry, the influence of feed production on the development of animal husbandry are analyzed. The directions of increasing the economic efficiency of forage production by increasing the proportion of proteins in the feed used, improving their structure by expanding the crops of perennial legumes and legume-cereal grass mixtures are proposed.

Ecological Assessment of Sulfur Content in Agroecosystems of the Central Black Earth Region of Russia

Studies were carried out on the territory of the steppe and forest-steppe zones of the Central Black Earth Region of the Russian Federation. The objects of research were the soil of nature reserves and arable chernozems that were not touched by agricultural activity, typical and common, the vegetation cover of natural biocenoses and agroecosystems, and organic fertilizers. The studies found that the background content of mobile sulfur in virgin soils is at a low level: 2.31 mg/kg - in a typical chernozem and 1.83 mg/kg - in an ordinary chernozem. According to agrochemical monitoring of arable soils carried out during 2015-2018, an increase in the weighted average content of mobile sulfur by 0.7 mg/kg to 3.3 mg/kg was established, compared to 2005-2009. However, the proportion of soils low on this element remains quite high - 90.3%. The main source of sulfur supply to the soils of agroecosystems (7.52 kg/ha) are organic fertilizers, the doses of which in 2015-2018 increased to 8.1 tons/ha. The average sulfur content in the steppe mixture of herbs of reserves is 0.3-0.4 mg/kg. The highest sulfur content among perennial legumes is clover (0.61%) and alfalfa (0.60%), and among legumes - soybeans, containing 0.34% of the element in grain and 0.21% - in straw.

Methods of improvement of degraded haymaking fields in the forest-steppe of the Ob river region

The results of investigations on the formation of high-yielding haymaking fields with the sowing of perennial legumes with different methods of processing the sod of degraded hayfields have been presented in the paper. The purpose of the work was to determine the most effective methods that contribute to increasing the yield and feed quality of degraded haymaking. The most effective methods that contribute to increasing the yield, feed quality and productive longevity of degraded haymaking have been determined. The content of perennial legumes in the herbage was registered: in the variant with plowing of turf it was 88 %, with milling – 80, with disking – 70 %. The highest yield has been obtained on the variant with the radical improvement 17,3 t/ha herbage and 3,64 t/ha of dry weight, which exceeded the indicators of the control variant by 3,6 times. It has been revealed that with the radical improvement of degraded haymaking (plowing + disking), the yield of feed units reached 1,74 t/ha, digestible protein – 0,25 t/ha, the amount of digestible protein per 1 feed unit was 140 g. These indicators during the sod disking were: 1,55 t/ha, 0,22 t/ha and 135 g, respectively. When strip-seeding of perennial legumes, the variant with the width of the treated strip of 60 cm has been distinguished. The collection of feed units amounted to 1,61 t/ha, of digestible protein – 0,18 t/ha. In the control variant (degraded haymaking), the collection of feed units was 0,38 t/ha, of digestible protein-0,025 t/ha. An economic assessment of the methods of improving degraded haymaking has shown that strip sowing of perennial legumes turned out to be the most effective method of improvement in the forest-steppe zone in Western Siberia. The net income depending on the option of strip sowing amounted to 3751–4278 rubles/ha, the level of profitability – 71–87 %. During the radical improvement, the economic indicators were slightly lower – 3959 rubles/ha and 57 %, respectively.

Vasyl Pastushenko’s Scientific School in the Development of Soil Protection Technologies in Ukraine

The article describes the achievements of scientists of the leading scientific school of thought on the development of soil protection technologies in Ukraine, founded by Vasyl Onufriievych Pastushenko (1907–1999). The introduction of the years of the scientists’ research in Ukrainian farms with different soil and climatic conditions has resulted in efficient production of quality agricultural products and improvement of environmental conditions, particularly, the improvement of soil protection crop rotations with the cultivation of mixtures of perennial legumes and siderates, anti-erosion cultivation of soil across the slopes, fertilizer and mulching, etc. Among the followers of Vasyl Pastushenko are the well-known scientists P. I. Boiko, V. O. Borodan, V. V. Kulbida, H. K. Medvid, I. H. Predko, I. H. Zakharchenko, and others. The purpose of the article is to review the achievements of these scientists in the development of soil protection, anti-erosion measures in different soil and climatic conditions in Ukraine.

Belowground Dynamics Influence Nitrogen Cycling and Crop Productivity in Diversified Corn Systems

Ecological nutrient management is a strategy that can help create resilient cropping systems and reduce the negative impact that agricultural systems have on the environment. Ecological nutrient management enhances plant-soil-microbial interactions and optimizes crop production while providing key ecosystem services. Incorporating perennial legumes into crop rotations and implementing no-till to enhance organic nitrogen (N) soil pools could reduce the need for inorganic N fertilizer inputs and lead to improved soil health. Plant and soil N pools need to be further quantified to understand how to enhance soil health across a range of agroecosystems. This paper aims to quantify plant and soil N pools in systems contrasting in crop perenniality (corn–corn, corn–soy, and corn–forage–forage) and tillage intensity (chisel till vs. no-till). Key plant, soil, and organismal metrics of N cycling were measured including fine root production, N-Acetyl-B-Gulcosaminidase (NAG) enzyme activity, and soil protein, nematode enrichment opportunist (fungal and bacterial feeding nematodes) and the nematode Enrichment Index. Fine root production was determined using in-growth mesh cores. Findings reveal that monoculture cropping systems with reduced tillage intensity and rotations with perennial legumes had significantly greater fine root N (FRN), soil protein and NAG enzyme activity (p < 0.05) relative to corn-soy. Additionally, nematode bacterivore enrichment opportunists (b1) were significantly reduced in corn-corn systems when compared to all other crop rotation systems. Correlation analyses indicated positive and significant relationships between FRN and soil protein (p < 0.05). These results demonstrate that lengthening crop rotations with perennial legumes and incorporating no-till management can increase organic N inputs, N mineralization rates, and organic N storage. Such ecological approaches to management have the potential to reduce the need for inorganic N inputs, while increasing long-term soil health and crop productivity.

Ways to improve low-yield hayfields and pastures in arid areas

Relevance. An analysis of the development of feed production in the Stavropol Territory shows that at present, due to the low productivity of natural forage lands, the level of feed production does not meet the requirements for the development of animal husbandry. Illiterate anthropogenic influence in the dry-steppe regions of the region, where about 70% of the number of sheep and 30% of the number of beef cattle are located, led to the fact that up to 300 thousand hectares of hayfields and pastures were subjected to erosion and deflation. However, in recent years, the process of improving forage land has been reduced to a minimum. Therefore, the process of restoring the forage productivity of hayfields and pastures should be given close attention. To this end, in the zone of dry steppes we conducted research on the selection of perennial legumes and grasses of a new generation to create highly productive grassland agrophytocenoses of long-term use.Methods. The experiments were carried out in the conditions of arid and extremely arid zones of the Stavropol Territory. The objects of research were perennial legumes and cereals and their herb mixtures. Restoration of degraded hayfields and pastures was carried out by means of amelioration and superficial improvement.Results. According to our research, by enriching the degenerated grass with valuable legumes and cereals in terms of forage it is possible to significantly increase its productivity and quality. In extremely arid and arid zones the most effective mixtureswere ones involving 4 and 5 components, which yield reached 15.3–23.8 t/ha of green mass, and the yield of feed units per 1 ha was 1.9–2.6 t/ha. The increase in the productivity of the improved herbage had a positive effect on the feed capacity of the land, which increased to 0.83–1.30 conventional heads per 1 ha.

Productivity of long-term bean grass in single-species and compatible with anwless bromegrass feed agrophytocenoses

Goal. Establish the best perennial legumes when grown in single-species and compatible fodder agrocenoses with stokolos boneless and the effectiveness of the use of nitrogen-fixing and phosphorus-mobilizing bacterial preparations, as well as liming. Methods. General scientific − hypotheses, inductions and deductions, analogies, generalizations and special − field, laboratory, mathematical and statistical, computational and comparative. Results. Based on the generalization of literature sources, it is proved that the creation of sown grasslands, with high content of perennial legumes on meadows and arable lands, which are derived from intensive cultivation is one of the most promising areas of organic onion growing. Productivity of single-species crops of perennial legumes and their mixtures with boneless stalk on average for five years after the yield of 1 ha of dry mass in the version without fertilizers ranged from 5.12 to 8.38 tons, which is 1.7−2.5 times more in comparison with a grassy grass stand which is formed from one-species crops of a stokolos of a boneless. The highest productivity and level of symbiotic nitrogen accumulation (191−266 kg / ha) were provided by agrocenoses with the participation of alfalfa, and the lowest - meadow clover. The efficiency of soil liming during sowing of grasses and application of inoculation of seeds of perennial legumes with nitrogen-fixing and phosphorus-mobilizing preparations is given. Changes in the chemical composition of feed under the influence of the studied factors are also shown. Conclusions. Different types of perennial legumes and their mixtures with boneless stalk without fertilizers provide productivity in the range of 5.12−8.38 t / ha of dry weight, which is 1.7−2.5 times more than the grass cover, which is formed from single-species sowing of stokolos bezzostoy. Inoculation of perennial legume seeds with nitrogen-fixing and phosphorus-releasing microbiological preparations increases the productivity of perennial legumes and their mixtures with cereals by 2−6%, and soil liming before sowing – by 3−11%. The greatest effect is provided by the combined use of these bacterial drugs. Alfalfa sowing responds best to their use and liming.

Determining the content of nitrogen and some macroelements in the dry mass of perennial leguminous plants

The aim of this study was to determine the content of elements N, P, K, Ca, and Mg in the dry mass of perennial fodder legumes, mowed in the optimal growth phase. The experiment with perennial legumes of alfalfa (Medicago sativa), red clover (Trifolium pretense) and bird's-foot trefoil (Lotus corniculatus L.) was set up as a random block system in four replicates on valley-brown soil and was conducted for two years. The green mass of perennial legumes in the first and second mowing was harvested at the end of budding/ beginning of flowering phase. In the third and fourth regrowth, mowing of the biomass was done after 5 weeks. Immediately after each mowing, representative sample of green biomass was taken from each replicate of each legume tested. The content of nitrogen, phosphorus, potassium, calcium, and magnesium in the dry plant material was determined. The content of nitrogen and potassium in the fodder of alfalfa and red clover was higher in the first year of the study, which was not the case for bird's-foot trefoil. The dry matter of alfalfa on average had the highest content of nitrogen (39.8 g kg-1 DM) and calcium (19.6 g kg-1 DM), bird's-foot trefoil of phosphorus (10.6 g kg-1 DM) and potassium (26.1 g kg-1 DM), and red clover of magnesium (3.7 g kg-1 DM). In the dry mass of bird's-foot trefoil the average content of nitrogen was 39.0 g kg-1 DM, phosphorus 10.6 g kg-1 DM, potassium 26.1 g kg-1 DM, calcium 15.7 g kg-1 DM, and magnesium 3.5 g kg-1 DM.