Row Crop Rotation Research Articles

Decrease in fertility of typical chernozem due to long-term anthropogenic pressure in grain-beet crop rotations

The saturation of sugar beet rotations under different fertilizer application systems and long-term cultivation induces significant changes in soil properties, leading to decreases in humus content, mineral nitrogen, phosphorus, and potassium. The study was conducted in a stationary multifactorial experiment in grain-beet crop rotations: crop rotation, row-crop, and grain-row crop rotations with the application of 40 t/ha of manure under sugar beets + NPK 100:90:90 and a variant without fertilizers. The paper presents the results of monitoring changes in humus content during each rotation, reduction of humus reserves in the plow layer, and physicochemical and agrochemical soil indicators. In the variants without fertilizers, we observed 0.24–0.41% decline in humus content in all crop rotations during 3 rotations of ten-field crop rotations (30 years). Overall, there occurred 0.89–1.00% decrease over 50 years of anthropogenic influence, equivalent to 31.8–35.7 t/ha, or 23.1–26.1% of initial reserves per hectare. Despite application of 40 t/ha of manure + NPK 100:90:90 under sugar beets, humus loss was 27.5 t/ha in the row-crop rotation and 16.8 t/ha in the grain-row crop rotation. Fertilizer application led to increase in exchangeable and hydrolytic soil acidity. With the application of 6.7 t/ha of manure + NPK 53:42:42 per 1 ha of crop rotation area, there was a tendency towards increase in mineral nitrogen content, mobile phosphorus doubled to 280.1–302.8 mg/kg compared to the variant without fertilizers, and exchangeable potassium decreased regardless of the fertilization system, which was associated with its utilization by plants. Sugar-beet yield increased to 44.76 t/ha in the crop-rotation under the organo-mineral-fertilizer application system, exceeding the spring wheat rotation by 4.63 t/ha and the variants without fertilizers by 2.45–2.72 times. Therefore, the modern fertilizer application system under sugar beets did not ensure stabilization of humus content in the soil and increased its acidity. It is necessary to more broadly use cover crops in crop rotations, incorporate crop residues, and apply biological preparations to improve soil fertility.

Potential gains in soil carbon and nitrogen as a result of systems perenniality: Insights from on‐farm experiments and soil organic matter fractions

AbstractUnderstanding soil organic matter (SOM) dynamics along gradients of land intensification is critical to guide conservation goals towards improvements in soil carbon (C) and nitrogen (N) storage. In this study, we clarified (a) how the C and N concentrations within SOM fractions of distinct ecological relevance responded to soil management representing a cropland‐grassland gradient and (b) how these operationally defined fractions affected soil physicochemical and biological properties. We compared sites with annual row crop rotations with and without cover crops (i.e. cropland soils) with perennial grassland sites (i.e. reference soil) by sampling near‐surface soils from statewide on‐farm cover crop experiments replicated across four agro‐ecoregions in Midwest USA. Soil management had a significant main effect on C and N content in SOM fractions, but responses were site‐ and fraction‐specific. We found that C content of free particulate organic matter and water‐extractable organic matter (WEOM) of reference soils were 58%–76% and 31%–59% greater than those of the cropland soils in two of the four sites. Differences in N content of WEOM because of soil management were observed in two of the four sites. These reference soils had between 40% and 60% greater N than cropland soils. Additionally, the N content of aggregate occluded POM (o‐POM) of reference soils was three times greater than those of the cropland soils in one of the four sites. Broadly across bulk and SOM fractions, high declines in cropland C and N relative to reference soils were observed in non‐irrigated and strip‐till sites and coarse‐texture soils. Free and o‐POM C and N were strongly associated with aggregate stability, water infiltration and enzyme activity, whereas C and N contents of WEOM and MAOM were correlated with soil's ability to hold onto essential nutrients (e.g. calcium, magnesium, potassium and sodium). Although the potential of cover crops to drive changes on ecologically meaningful SOM fractions is less pronounced in the short (3 year) term, the findings demonstrate the potential of continuous living cover as an approach to agroecosystem design to improve soil functions closely related to SOM characteristics.

Change of available soil moisture reserves in agrocenoses of winter wheat in short rotation crop rotations

The article presents the results of changes in available soil moisture in winter wheat crops in four short-rotation crop rotations. The research was carried out during 2012-2021 at the experimental field of the Belotserki National Agrarian University of the Kyiv region. The soil of the experimental field is a typical chernozem with a low humus content of average loamy humus in the 0–30 cm soil layer of 3,7–3,9 %. Four short-rotation crop rotations were studied (sunflower saturation 10 %); cereal grain (sunflower saturation 20 %); specialized seedbed (sunflower saturation 30 %); rowing (sunflower saturation 40 %). It was established that the reserves of available moisture for the period of winter wheat sowing were the highest in the grain-row specialized crop rotation, where wheat was sown after buckwheat with 257,2 mm in the 0–150 cm layer, 78,5 mm in the 0–50 cm layer. In the crop rotation in the 0–150 cm layer, they were 204,3 mm, in the 0–50 cm and 50–100 cm layers 59,4 and 52.4 mm, which is 19,1 and 15.0 less than in the grain-row crop rotation mm. During the crop rotation, the reserves of available moisture for the harvesting period were 1372 m3/ha, grain-rowing – 1154 m3/ha, specialized grain-rowing and row-rowing – 1327 and 928 m3/ha, which affected the total moisture consumption. The highest consumption of available moisture was observed during row crop rotation - 4029 m3/ha, while during crop rotation the available moisture reserves were 4032 m3/ha. The coefficient of moisture consumption was the highest in specialized and row-row crops – 97,8 and 90,7 m3/t, respectively, while for crop rotation – 70,7, grain-row crops – 85,2 m3, which was less than row crops by 5,5 and 20 m3/t.

Assessment of the phytosanitary state of agricultural seedings using agrobiotechnology

The results of weed infestation of cultivated oats and maize by the phases of their development and the manifestation of the signs of oat septoria affection in the experiment with an applied agrobiotechnology, including the use of biological preparations Trichoplant, SK (based on Trichoderma) and Biogor-Zh (based on Lactobacillus), nitrogen fertilizers (at the rate of 10 kg of NPPN per 1 ton of straw) and lime at the rate of 1.5 t/ha when using crushed by-products as fertilizer are presented. The work was carried out in the scientific and production experiment, founded in 2018 and located in Kursk Region, in Medvensky District, settlement of Panino, in two fields. In 2022 in the first field (cereal crop rotation) cultivated oat (Avena sativa L.) of the variety “Borets” was grown with buckwheat as a previous crop, in the second field (cereal and row crop rotation) maize for grain (Zea mays L.) of the variety “Delitop” was cultivated with winter wheat as a previous crop. The results were obtained in the following variants: 1. Control (no fertilizers and afterharvesting residues); 2. Crushed by-products of the crop as a background; 3. Background + nitrogen fertilizers; 4. Background + lime; 5. Background + biopreparations; 6. Background + biopreparations + nitrogen fertilizers; 7. Background + biopreparations + lime. The number of weeds less by 36.7 and 76.4 % related to the control, respectively, was found when biopreparations with nitrogen fertilizers were applied in maize and cultivated oats in the phase of ear emergence. The number of oat plants affected with ceptoria in the variants with biopreparations applied in the tillering phase and with combined application of biopreparations and lime in the phase of ear emergence was by 14.9 and 22.9 % less as compared to the control, respectively.

ТРАНСФОРМАЦИЯ ФИЗИКО-ХИМИЧЕСКИХ СВОЙСТВ ЧЕРНОЗЕМА ПРИ ДЛИТЕЛЬНОМ ПРИМЕНЕНИИ ОСНОВНОЙ ОБРАБОТКИ ПОЧВЫ В СЕВООБОРОТЕ

In the process of development of agriculture, methods and methods of tillage are being improved. Soil cultivation is determined by many factors, which can be natural and anthropogenic. Mechani-cal processing changes the physical, physico-chemical and biological processes in the soil. The purpose of the research is to establish the nature of the transformation of the physico–chemical properties of the soil under the influence of basic tillage in the grain-grass crop rotation with spring rape. In a stationary experiment in 9-full grain-grass crop rotation (1–clover of 1 year of use for one mowing, 2 – winter wheat, 3 - sugar beet, 4 – spring barley, 5 – peas, 6 – winter wheat, 7 – spring rapeseed, 8 – corn for silage, 9 - bar-ley + clover) the following technological operations of tillage were studied: dump, flat-cut, combined. Crop rotation crops are cultivated according to intensive technologies recommended for the Central Chernozem region. Pre-sowing treatment on all variants consisted of early spring harrowing with subsequent cultivation to the depth of seed embedding. The combination of various techniques and methods of cultivation in the grain-grass row crop rotation makes it possible to change many processes both in the direc-tion of increasing and worsening the effective soil fertility. According to the degree of adverse im-pact, the methods of tillage are arranged in the following increasing sequence: combined, dump, flat-cut for crop rotation crops. To preserve the physical and chemical properties of the soil and increase the productive capacity of chernozem, preference should be given to combined cultiva-tion, where plowing in a nine-field crop rotation takes from 33 to 45%. In this variant, 4.94 t/ha of production units were collected for rotation of the crop rotation, 4.57 t/ha of production units were collected for flat–cutting, and 4.81 t/ha of production units were collected for dump.

Humus state and nutrient regime of typical chernozem depending on fertilisation in short crop rotations

The fertiliser system is the most effective factor in the intensification of crop cultivation technologies. The basis for scientifically sound fertiliser application systems, along with obtaining the planned level of yield of the appropriate quality, is the study of the organic matter content and soil nutrient regime during crop rotation. The purpose of this study was to determine the mineral nitrogen, mobile phosphorus, exchangeable potassium, and humus content in typical chernozem under different fertilisation systems in short-term crop rotations. To solve the problem of soil fertility, an important approach is to conduct field and laboratory research to determine changes in the humus state according to Tyurin, nitrogen, phosphorus, and potassium regimes of the soil according to Machigin, and dispersion methods to determine the reliability of experimental data. As a result of the research, it was found that the highest humus content in the soil was recorded under the organic-mineral fertilisation system at the end of the second rotation in the grain crop rotation by 0.13% compared to the fruit crop rotation. The use of a mineral fertiliser system in a row crop rotation reduced the humus content by 0.12%. An increase in the humus content of typical chernozem was recorded under fruit crop rotation and grain-row crop rotation. The organic-mineral fertilisation system tended to increase the mineral nitrogen content of the soil compared to the other systems. The mineral nitrogen content of the mineral fertilisation system decreased by 5.5 mg/kg of soil compared to the unfertilised variant. Under the organic-mineral and mineral fertilisation system, the content of mobile phosphate increased in all crop rotations. The content of mobile phosphorus in the tilled crop rotation was substantially reduced compared to the fruit crop rotation and grain-row crop rotation. The highest content of exchangeable potassium in the soil was recorded under the mineral fertilisation system. The materials of the publications are of practical importance in the analysis of the main elements of mineral nutrition of typical chernozem in short crop rotations

Soil carbon storage and compositional responses of soil microbial communities under perennial grain IWG vs. annual wheat

The introduction of novel perennial grains into annual row crop rotations is proposed to increase soil ecosystem services and enhance plant-soil-microbial linkages because perennials provide deeper root systems and more continuous ground cover than annuals. While soil microbial communities underpin many ecosystem services, we know little about how soil microbial composition and diversity, and soil carbon storage, differ between soils of annual vs. perennial grain crops. We measured soil fungi: bacteria (F/B) ratios and soil carbon within the novel perennial intermediate wheatgrass (IWG; trademarked Kernza®) and tilled annual wheat and compared soil microbial diversity and community composition within their rhizosphere, shallow bulk soil (0–15 cm) and total bulk soil (0–90 cm). After three years, soil depth explained 30–40% and 12–22% of the variance in bacterial and fungal community composition, respectively, while crop type explained 10% and 9–16% of the variance, respectively. Fungal communities were most impacted by crop type in the rhizosphere and shallow bulk soil and less sensitive to differences in soil depth. In contrast, crop type had a smaller effect on bacterial communities which were more influenced by soil depth. IWG trended higher in soil carbon mass at 0–30 cm (p = 0.22) and had a higher (F/B) ratio than tilled annual wheat at depths below 15 cm, but tilled annual wheat had higher soil carbon concentration (p = 0.12) and soil carbon mass (p = 0.09) at the 60–90 cm soil depth. Our results indicate that fungi were more responsive than bacterial communities to crop type and that IWG has a higher fungal biomass and different fungal community composition than annual wheat at depth. However, despite these distinct differences in fungal communities in IWG compared to annual wheat, the differences did not translate into greater soil carbon mass in IWG at depth.

Efficiency of different tillage, fertilization systems under short crop rotation and their influence on phytosanitary condition of agrocenoses

The main restraining factor of the widespread introduction of minimization of mechanical tillage into the domestic agricultural practice was and remains the problem of deterioration of the phytosanitary state of agrophytocenoses and the soil environment. Intensive use of pesticides, especially in violation of the regulations of their use, does not solve the problem, and often, on the contrary, aggravates it. Ukraine ranks sixth-seventh in the world in terms of contamination of plant products with pesticide residues. Agricultural practice proves that all pesticides are toxic to humans, and many of them also have mutagenic activity. They also cause great harm to living nature, suppressing the biological activity of soils, destroying pollinating insects, etc. Given this, the value of mechanical cultivation in regulating the phytosanitary state of agrobiocenoses and soil will increase, especially in ecological and organic agriculture. Research (2020– 2022) on the chernozems of the typical experimental field of Bila Ttserkva National Agrarian University established changes in the phytosanitary state of the agrobiocenoses of the field specialized grain five-field crop rotation and its productivity under different systems of the main cultivation of the chernozem soil of a typical low-humus medium loam in the Right Bank Forest Steppe of Ukraine, namely: shelf-disc the treatment has an advantage only in terms of significant limitation of dark brown spotting on winter wheat for sowing after buckwheat. In the remaining cases, it was significantly inferior to control. Indicators of the phytosanitary state of agrobiocenoses significantly worsen with constant soil disking. Discless tillage has an advantage only in terms of significant limitation of dark brown spotting on winter wheat after sowing after buckwheat. In the remaining cases, it was significantly inferior to control. Indicators of the phytosanitary state of agrobiocenoses significantly worsen with constant soil disking. The abundance of weeds is insignificantly lower under differentiated than shelf-disc cultivation. Fertilizer systems did not affect weediness, but worsened other indicators of phytosanitary status. With differentiated cultivation, the population of larvae of the winter weevil and the prevalence of helminth sporous root rot, powdery mildew and septoriosis of winter wheat after buckwheat, as well as the abundance of the meadow butterfly and wireworm in the agrophytocenosis of corn, are significantly reduced. Productivity of crop rotation is almost at the same level for shelf-disc and differentiated tillage. With chisel-disk and disk processing, it is significantly reduced. In a five-field field row crop rotation, differentiated tillage is recommended, in which deep (25–27 cm) plowing is performed only in one field under the row crop, where manure is applied, and in the rest of the fields, plowing and disc tillage to different depths, taking into account biological features of agricultural crops.

Reductions in soil water nitrate beneath a perennial grain crop compared to an annual crop rotation on sandy soil

Nitrate (NO3--N) leaching into groundwater as a result of high nitrogen (N) fertilizer rates to annual crops presents human health risks and high costs associated with water treatment. Leaching is a particularly serious concern on sandy soils overlying porous bedrock. Intermediate wheatgrass (IWG) [Thinopyrum intermedium (Host.) Barkw. & D.R. Dewey], is a perennial grass that is being bred to produce agronomically and economically viable grain, which is commercially available as Kernza®. Intermediate wheatgrass is a low-input crop has the potential to produce profitable grain and biomass yields while reducing NO3--N leaching on sandy soils compared with common annual row crop rotations in the Upper Midwest. We compared grain yields, biomass yields, soil solution NO3--N concentration, soil extractable NO3--N, soil water content, and root biomass under IWG and a conventionally managed corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] rotation for 3 years on a Verndale sandy loam in Central Minnesota. Mean soil solution NO3--N was 77–96% lower under IWG than the annual crop rotation. Soil water content was greater under annuals compared to IWG early in the growing season, suggesting greater water use by IWG during this time. Interactions between crop treatments and depth were observed for soil water content in Year 3. Root biomass from 0 to 60 cm below the soil surface was five times greater beneath IWG compared to soybean, which may explain differences in soil extractable and solution NO3--N among crops. With irrigation on coarse structured soils, IWG grain yields were 854, 434, and 222 kg ha−1 for Years 1–3 and vegetative biomass averaged 4.65 Mg ha−1 yr−1; comparable to other reports on heavier soils in the region. Annual crop grain yields were consistent with local averages. These results confirm that IWG effectively reduces soil solution NO3--N concentrations even on sandy soils, supporting its potential for broader adoption on land vulnerable to NO3--N leaching.

Ascertaining land allocation decisions of farmers about the adoption of carinata as a potential crop for sustainable aviation fuel production in the Southern United States

AbstractThe adoption of a bioenergy crop is affected by various factors, including but not limited to the characteristics of farmers, farm economics, market forces, and physical environment. This study develops a spatially explicit agent‐based model for ascertaining the adoption rate of carinata (Brassica carinata) among the farmers in the Little River Experimental Watershed located in the southern state of Georgia in the United States. Each farmer's adoption behavior is modeled using the profitability difference between traditional crop rotations (with and without carinata at different contract prices), the adoption rate of neighboring farmers, and their land allocation decisions from managing a risky portfolio of enterprises. Carinata production in the winter season once every 3 years has no conflict with the most profitable and popular traditional row crop rotations, such as cotton‐cotton‐cotton and cotton‐cotton‐peanut, to a larger extent. The results show that 28% and 85% of farmers in the watershed will adopt carinata after 33 years at a contract price of $13/bushel (bu) under two different assumptions of low (2.5%) and high (5%) initial neighborhood adoption rates. The proportions of land allocated to carinata to the total farmland under field crops are 38% and 85% after 33 years under the same low and high neighborhood adoption rates, respectively. Our results suggest that fixing the appropriate contract price of carinata will bring additional profits to farmers without any significant foreseeable agronomic risks, thereby increasing the adoption rate of carinata at a regional level.

Баланс гумусу і поживний режим зрошуваного ґрунту за різних систем основного обробітку та удобрення

The article presents an analysis of the results of experimental research in a stationary field experiment to determine the peculiarities of the formation of humus reserves and the nutrient regime in the arable layer of the dark chestnut soil (Haplic Kastanozem) under the influence of different fertilization and main cultivation systems. The purpose of the research: to establish the patterns of transformation of by-products of agricultural crops of crop rotation into humus and the main elements of mineral nutrition of plants under organic and two organo-mineral fertilization systems against the background of five systems of main cultivation in a 4-field row crop rotation on irrigated lands in the area of operation of the Ingulets irrigation plant systems. The research was conducted in the stationary experiment of the Institute of Irrigated Agriculture of the National Academy of Sciences in the Kherson region of Ukraine during 2016-2020. The following indicators were used to analyze the effectiveness of the combined application of fertilization systems and the main tillage: mass of post-harvest residues for each of the crop rotations; stocks of humus in the arable layer; humus balance; the mass of nitrogen, phosphorus and potassium that reached the soil with plant residues; ecological and economic effect (UAH/ha); energy gain (GJ/ha). As a result of experimental studies, it was found that the formation of humus reserves in the soil depends on the mass of post-harvest residues of crop rotation and the methods and depth of their wrapping. The most favorable conditions for the accumulation of leaf-stem mass of crop rotation crops and the formation of a positive balance of humus with an average annual increase of 2.02 t/ha were provided by the organo-mineral fertilization system using the by-products of crop rotation crops and a dose of mineral fertilizers N120P60 against the background of differentiated main cultivation with one slotting to a depth of 38-40 cm per rotation.

ЕФЕКТИВНІСТЬ ОСНОВНОГО ОБРОБІТКУ ҐРУНТУ ТА МІНЕРАЛЬНОГО ЖИВЛЕННЯ У ВИРОЩУВАННІ СОЇ НА ЗРОШЕННІ

In the article the brought results over of experimental researches of influence of different methods and depth of soil basic tillage and doses of mineral fertilization on agrophysical properties and productivity of soybean. A purpose of researches is establishment of the most effective methods of soil basic tillage and doses of application of mineral fertilizers at growing of soybean in row croprotation on the irrigation of south of Ukraine and their influence on a height and development of plants, forming of harvest and quality of seed. During an experiment used the field, in-gravimetric, visual, laboratory, calculation-comparative, mathematically-statistical methods with the use of confessedly methods and methodical recommendations. For determination of efficiency of action of soil basic tillage and doses of fertilizers on the productivity of soybean five variants of methods of basic tillage were stopped up and three variants of fertilizer systems: organic and two organo-mineral with doses bringing of mineral fertilizers - N30P60, N60P60 on a background of post harvesting bits and pieces of cultures of crop rotation and optimal mode of irrigation. Results. The changes of agrophysical properties happened under act of the systems of soil basic tillage, nourishing mode, that stipulated creation of different terms for a height and development of culture and forming of harvest. The productivity of seed of soybean at plowing on a 25-27 cm averaged for five years on a background the dose of fertilizers of N60P60 of 4,22 t/ha. At the combined tillage which united disk loosening on a 14-16 cm with slotting on a depth a 38-40 cm, 4,12 t/ha of seed of soybean is got in the system of differentiated-1 soil tillage. On the average on a factor B (system of fertilizer), the productivity of seed of soybean at organic system of fertilize made 2,38 t/ha. Bringing of dose N30P60 assisted the height of harvest on 0,84 t/ha, and N60P60 on 1,39 t/ha, or on 35,2 and 58,4% accordingly. Conclusion. In the short row crop rotation on the irrigated lands of south of Ukraine the most favorable terms for a height, development and forming of harvest of soybean on dark-chestnut soils are created in the systems of plowing basic soil tillage with the turn of layer or differentiated- 1 tillage with the deep loosening under soybean or shallow on a background slotting on a depth a 38-40 cm under a previous culture.

No-till technology has limited potential to store carbon: How can we enhance such potential?

No-till is a top soil conservation practice, but if it will be used as a C sequestration strategy, it needs enhancement. Companion practices including N fertilization and irrigation do not often result in net C sequestration or some are unavailable (i.e., biochar) for a large-scale application. Adoption of aggressive or transformative no-till companion practices that genuinely remove CO2 from the atmosphere through photosynthesis and sequester it in the soil as C should be considered. Enhancing both cover crops and crop rotation complexity can be an aggressive biological strategy to boost no-till performance; yet this has not been much discussed. Enhancing cover crops by increasing both the cropland area under no-till cover crops and cover crop biomass production through biomass yield maximization strategies can store more C in the soil than current no-till cover crop management practices. Additionally, inserting multi-year perennial or forages including grasses and legumes into existing no-till row crop rotations could store an additional amount of C. These no-till enhancement practices may not only increase C sequestration in the soil but also boost the overall resilience and ecosystem services from agricultural lands. Their potential can be particularly greater in low C (below C saturation) than high C (at or near C saturation) no-till soils.

Economic efficiency of using urban sewage sludge in combination with zeolite-containing agricultural ore at cultivating crops of grain fallow row-crop rotation

Further intensification of agricultural production and crop yield growth will be accompanied by an increase in the cost of non-renewable energy, including through the increasing use of fertilizers. Therefore, in the future, it is important to develop and use energy-efficient production technologies that use less energy to produce agricultural products. The paper shows the influence of reclamation norms of urban sewage sludge (USS) and their combinations with natural zeolite on the economic efficiency of growing crops of grain fallow crop rotation. Studies showed that the use of urban sewage sludge as a fertilizer and the integrated use of USS with zeolite-containing agricultural ore pay off economically. The maximum net income was provided by the combined application of urban sewage sludge at the rates of 160 and 180 t/ha in combination with zeolite. The amount of conditional net income from their application was 13.51-13.62 thousand rubles/ha.

Продуктивність просапної сівозміни за мінімізованого і нульового обробітків ґрунту в умовах зрошення півдня України

Goal. To determine the productivity of 4-field crop rotation with minimized and zero main tillage and organomineral fertilizer systems using post-harvest residues and green manures in the conditions of irrigation of the South of Ukraine. Methods. Field, quantitative, visual, laboratory, computational, mathematical, and statistical methods using generally accepted in Ukraine methods and guidelines. Results. The data are given of experimental researches of formation of productivity of cultures of 4-field row crop rotation at various basic cultivation of soil and fertilizers on the irrigated lands in a zone of action of the Kakhovka irrigation system. It was found that the highest productivity was provided by crop rotation on the background of different depth chisel main tillage, which under the organomineral fertilizer system using after-harvest residues and green manure on the background of different doses of mineral fertilizers provided 8.06–9.10 t/ha of grain units. The use of green manure for fertilizer helped to increase crop rotation productivity with differentiated and shallow (12–14 cm) single-depth disc loosening by 6.5%, with different depth chisel — by 7.4, for zero — by 9.2%. Conclusions. On dark chestnut soil in the conditions of irrigation of the South of Ukraine, the highest productivity was provided by row crop rotation with different depths of shelfless main cultivation on the background of organomineral fertilizer system with N120P40 application and use for fertilizing of by-products of crop rotation and green manure.

Productivity of grain row crop rotations at the different systems of basic tillage in the area of action of Ingulets irrigatory system

Productivity of grain row crop rotations at the different systems of basic tillage in the area of action of Ingulets irrigatory system

Ecological and economic efficiency of green manure in crop rotation on irrigated lands in the south of Ukraine

One of the ways to solve the problem of preserving soil fertility is the use of special soil protection measures and scientifically proven technologies. The main measures to increase crop productivity, preserve soil fertility and improve ecological state of the environment are the primary tillage and fertilization systems in modern high-intensity farming systems with scientifically proven methods, techniques, and depth of loosening, as well as doses of mineral and organic fertilizers. The article presents the results of experimental studies of changes in the humus reserves in the arable layer of the soil under the influence of longterm use of differentiated systems of primary tillage, in which different methods and depth of the primary tillage alternate during crop rotation, different depth (23–25 cm and 28–30 cm) subsurface chisel tillage, single-depth shallow (12–14 cm) disk and zero tillage, against the background of the fertilizer system using post-harvest green manure. The research was conducted during 2015–2019 on the irrigated lands of the Askaniya State Agricultural Research Station of the Institute of Irrigated Agriculture of NAAS, in the area of the Kakhovka irrigation system, in a fourfield row crop rotation with successive crop rotation of the following: soybean, winter wheat + mustard (postharvest for green manure), corn for grain, winter barley + mustard (postharvest for green manure). The soil of the experimental field is dark chestnut, slightly saline, medium loamy. Based on data from field, laboratory and analytical studies, it is established that in short-term row crops rotation on irrigated lands of southern Ukraine an effective measure to increase the fertility of dark chestnut soils is organic-mineral fertilizer systems with a mineral fertilizer dose of N120P40 (per hectare of crop rotation area), the use of spring mustard as fertilizer in post-harvest crops as well as the use of all by-products of crop rotation. Differentiated and different-depth subsurface systems of primary tillage against the background of organicmineral fertilization system provide productivity of short-term crop rotation at the level of 7.77 and 8.09 t/ha of grain units respectively, increase of humus by 1.25 and 1.33 t/ha, and total ecological economic efficiency of crop rotation operation by 61.50 and 64.63 thousand UAH/ha.

Biological activity of typical chernozemic soil under different systems of main tillage and crops fertilisation of a short crop rotation

The influence of four main tillage systems and four fertilization systems on biological reactivity of a plow layer of typical chernozemic soil under agrophytocenosis of five crops was investigated during four year research (2016–2019) of the stationary field grain row crop rotation. Loss of mass of flax linen in a plow layer of soil during two months of the study characterizing the intensity of cellulose-decomposing microorganisms under beard, beardless, differential and disc tillage made correspondingly 24.5; 22.7; 23.4 and 23.3 % – for soybeans; 16.3; 15.7; 15.9 and 16.2 % for winter wheat, 24.1; 22.8; 24.7 and 22.6 % – for sunflowers, 27.7; 24.1; 25.1 and 23.7 % – for spring barley, 21.9; 19.9; 22.4 and 19.0 % – for corn. Steady surface and beardless tillage strengthen the differentiation of a plow layer according to the intensity indices of flax linen decomposing while the beard one tillage decreases. The most heterogenic plow layer was observed under beardless tillage; it was a bit lower under disk tillage in a crop rotation. The intensity of flax linen decomposing on the top of a plow layer (0–10 cm) is the highest under beardless tillage and the lowest under beard tillage, while in the bottom (20–30 cm) of a plow layer an inverse relation can be observed. The intensity of carbon dioxide production by the soil under soybeans, winter wheat and spring barley is the highest under beard tillage and the lowest it is for soybeans under beardless and differential tillage, for winter wheat, sunflowers and spring barley under beardless tillage and for corn under disc tillage. For sunflowers and corn this index is higher under differential rather than under beard tillage in a crop rotation. The biological reactivity of a plow layer of a typical chornozemic soil increases as the fertilizers application rates increase. Crop rotation productivity is almost at the same level under beard and beard-beardless tillage in a crop rotation. Systematic beardless and surface disc tillage decreases this index significantly. Key words: soil, crop, crop rotation, tillage, fertilizers, flax linen, carbon dioxide, plow layer, heterogeneity.

Kura Clover Living Mulch Reduces Fertilizer N Requirements and Increases Profitability of Maize

Kura clover living mulch (KCLM) systems have been previously investigated for their incorporation into upper Midwestern row crop rotations to provide ecosystem services through continuous living cover. Reductions in soil erosion and nitrate loss to surface and groundwater have been reported, but factors affecting agronomic performance and nutrient management are not well defined. To achieve realized environmental benefits, research must develop agronomic management techniques, determine economic opportunities, and provide management recommendations for row crop production in KCLM systems. Two experiments were conducted in 2017 and 2018 to determine the response to N fertilizer application for maize production in KCLM. The first-year maize experiment followed forage management, and the second-year maize experiment followed maize after forage management. Eight fertilizer N treatments ranging from 0–250 kg N ha−1 were applied to each experiment and grain and stover yields were compared to conventionally managed maize hybrid trials that were conducted nearby. First-year maize did not need fertilizer N to maximize yield and profitability in either growing season, and second-year maize required a fertilizer N rate near local University guidelines for maize following soybean. The net economic return from maize grain and stover in the KCLM averaged over first and second-year maize experiments and 2017 and 2018 growing seasons were $138 ha−1 greater than the conventional comparison.

Ефективність агроекологічних заходів у сівозмінах на зрошуваних землях півдня України

Ефективність агроекологічних заходів у сівозмінах на зрошуваних землях півдня України