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Aim. To determine the level of trace elements in typical chernozem when using different systems of primary tillage.Materials and Methods. In the study systemic, chemical, comparative‐ analytical, field, laboratory and statistical methods were used and software packages Microsoft Excel and Statistica software packages. The following methods of primary tillage: moldboard plowing 20‐22 cm deep, combined tillage (disking+chisel) 20‐22 cm, surface tillage (disking) 8‐10 cm and without tillage (direct seeding) – No‐till were studied for the level of their impact on the change in the content in the soil of the mobile forms of Cu, Zn, Mn, Co, Ni, Pb and Cd.Results. Specific features of changes in the content of the mobile forms of trace elements when systematically using different systems of primary tillage were determined. Differentiation of the content of trace elements in the soil according to the depth of the treated soil layer was identified, especially in the variants with extremely opposite systems of primary tillage, i.e. plowing and No‐till. When plowing is used the accumulation of Zn, Mn, Co, Ni, Pb occurs in the 10‐20 cm soil layer. When No‐till is used the accumulation of trace elements is observed in the 0‐10 layer. Conclusion. Methods of tillage under study did not contribute to the accumulation of trace elements in the soil in doses exceeding MAC and did not result in soil contamination. The peculiarities identified of the accumulation and distribution of trace elements depending on the method of primary tillage used give the opportunity to regulate their amount in order to raise the level of nutrient content, to improve the nutrition of crops and to control heavy metals to prevent contamination of soil and plants.

Cover crops are essential tools in agroecosystems for reducing the reliance on synthetic inputs and associated environmental risks. Alongside their benefits to soil fertility, cover crops can control weeds by their competitive and allelopathic attributes. Laboratory and field experiments were conducted to assess the allelopathic potential of two cover crop species, rye (Secale cereale L.) and squarrose clover (Trifolium squarrosum L.), alone or in mixture, on seed germination and growth of arable weeds. Aqueous extracts of the two cover crops and their mixture were tested in a bioassay on Conyza canadensis (L). Cronq., Amaranthus retroflexus L. and Digitaria sanguinalis (L.) Scop. In vitro effects of aqueous extracts varied in a dose-dependent manner, with cover crops and weed species. All three extracts were able to reduce the germination of A. retroflexus (-87%) considerably. Inhibitory effects by rye and mixture extracts on radicle growth of all weed species ranged between 51 and 82%. Rye extract was the best at reducing shoot length of C. canadensis and D. sanguinalis (-39 to 44%), while squarrose clover was more effective on A. retroflexus (-79%). Plant extracts also delayed the germination time of weed species with substantial effect of the mixture on C. canadensisseeds. In the field experiment, no significant weed suppression was provided by cover crop residues incorporated as green manure compared to control plots, despite tillage being more effective in reducing weed density. Still, the cover crop mixture mulch controlled weed emergence significantly better than single cover crop mulches. The chemical characterization of cover crop residues, both shoots and roots, revealed a notable richness of allelopathic phenolic acids and flavonoids, that through slow decomposition may constitute potential natural herbicides. From the analysis of the aqueous extracts, other non-analyzed and/or unidentified water-soluble allelopathic compounds should underlie the phytotoxicity observed in vitro, at least for rye. For cover crop mixture, positive interactions among plant materials leading to a better release of allelochemicals and weeding effectiveness are discussed according to chemical profiles and field data. Our study demonstrated the allelopathic activity of the cover crops and their potential to be included in weed management strategies according to cropping system needs. Additional trials are needed to confirm the performance of cover crop residues under field conditions. Highlights - Rye and squarrose clover are cover crops with potential allelopathic effects. - Aqueous extracts of residues of rye, squarrose clover and their mixture reduced and/or slowed weed germination of A. retroflexus and C. canadensis in in vitro bioassays. - The aqueous extracts, depending on the concentration of residues, had inhibitory effects on radicle and shoot growth of A. retroflexus, C. canadensis and D. sanguinalis. - Under field conditions, mulch of a mix of rye and squarrose clover suppressed weeds better than the single species.

No-till (NT) has been said to conserve soil moisture, maintain or increase organic matter (OM), and improve crop production compared to conventional tillage (CT). However, very few studies have explored the effect of these under dry-land agriculture with occasional tillage where ploughing is performed only after several years of NT, especially in KwaZulu–Natal. The aim of this study was to assess the effect of tillage and fertilizer application on selected physicochemical soil properties under rain-fed maize production. Soil samples from NT, conventional tillage in the 5th season (CT-Y5), and annual conventional tillage (CT-A) with 0, 60, 120, 240 kg N ha−1 were taken at 0–10, 10–20, and 20–30 cm and analysed for pH, EC, exchangeable acidity, exchangeable bases, C:N, gravimetric water content, bulk density, and soil texture. Results showed that NT at 0 and 60 kg N ha−1 in 0–10 cm had higher bases, gravimetric water content, pH, and EC compared CT-Y5 and CT-A (p < 0.05). At 10–20 cm depth, CT-Y5 had higher gravimetric water content (0.17 gg−1), followed by CT-A, (0.13 g g−1), while NT had the least (0.11 g g−1) (p < 0.05) in the control treatment. Again at 20–30 cm depth, NT had higher (p < 0.05) bases than CT-Y5 and CT-A tillage practices at 120 and 240 kg N ha−1 application rate. Regression analysis of fertilizer application rate with both bases and gravimetric water content showed a strong relationship under NT. Better soil properties under both NT and CT-Y5 was attributed to residue cover and minimum disturbance of the soil, which encouraged infiltration, thus reducing runoff and evaporation from the soil surface. Accumulation of residue under conservation tillage enhances OM, which subsequently improves soil quality, whereas ploughing aerates the soil causing oxidation of OM, thus releasing H+ ions. Again, fertilizer application induces mineralization of OM, thus, higher fertilizer application rates result in low levels of carbon. NT is well-recommended in conserving soil quality while sustaining crop productivity.

Intensive agriculture has led to generation of a vast volume of agri-residue, prompting a reliance on conservation tillage techniques for prudent management. However, to ascertain the long-term impacts of these practices, the interrelation with the carbon fractions and the biological properties of the soil must be identified. Therefore, in a long-term experiment, five different treatments involving the incorporation of paddy straw as mulch or through disc harrow and farmer practice, including the partial burning of rice straw, were evaluated. After the harvesting of the wheat crop, soil samples collected from 3 different depths (0–15, 15–30 and 30–45 cm) were analyzed for various attributes critical to assessing soil health. Crop residue retention in both seasons (T4) improved carbon fractions, soil microflora viable cell counts and enzyme activities. The principal component analysis (PCA) revealed a positive interaction among the organic carbon, bacterial counts and soil enzyme activities. Thus, a positive impact of conservation tillage techniques involving a minimal disturbance was recorded as improvement in the soil properties, build-up of organic carbon, and wheat productivity in rice–wheat cropping systems.

Processes governing soil organic matter (SOM) decomposition and mineralization are important for soil fertility and ecosystem sustainability. However, in the sub-Saharan region, limited work has been conducted on SOM dynamics; therefore, there was an imperative need for this study. The objective of this study was to determine the phosphorus (P) and nitrogen (N) dynamics in soil under different tillage and fertilizer management practices. The field trial was arranged as a randomized split plot design, with tillage forming the whole plot and the fertilizer application rate being the sub-plot. The tillage techniques were no-till (NT), annual tillage (CT-ANNUAL) and conventional tillage every fifth season (CT-Y5), whereby NT was practiced for four consecutive seasons, and in the fifth season, conventional tillage was employed. For all these tillage techniques, urea fertilizer was applied in amounts of 60, 120 and 240 kg N ha−1 with a control for each tillage treatment. Ammonium and nitrate levels were determined calorimetrically. Sulfuric acid, at 1 M, along with 0.057 M ascorbic acid and molybdate reagent were used to extract the organic P from the soil and extractable P. The total N, ammonium, total P, organic P and extractable P in the surface soil under NT were higher (p < 0.05) compared to the values of both CT-Y5 and CT-ANNUAL. The high levels of total N, N mineralization, total P, organic P and extractable P under NT, compared to CT-Y5 and CT-ANNUAL, at the depth of 0–10 cm may be attributed to the accumulation of crop residues on the surface and less soil disturbance. Furthermore, nitrate was found in higher (p < 0.05) concentrations under CT-ANNUAL compared to CT-Y5 at all the application rates and depths. The ploughing of soil under CT-ANNUAL improves the aeration, which accelerates the decomposition of organic material and mineralization of organic N and P into soluble forms. No-till, at 60 kg N ha−1 and a 0–10 cm soil depth, had optimum total N, nitrate, ammonium, total P and organic P values, thus showing its salient impact on the maintenance of soil fertility. However, the conclusion drawn from this study is that CT-Y5, due to its average N and P pools, can be recommended to under-resourced farmers in sub-Saharan preferentially over both NT and CT-ANNUAL, because it does not require advanced technology and equipment and it sustains an average soil fertility.

Soil organic carbon (SOC) largely influences soil quality and sustainability. The effects of no-till (NT) and crop straw return practices (SR) on soil organic carbon sequestration have been well documented. However, the mechanism of soil bacterial community in regulating soil organic carbon under NT and SR remains unclear. In this study, we investigated the impacts of tillage (conventional tillage (CT) and NT) and crop straw return practices (crop straw removal (NS) and SR) on topsoil layer (0–5 cm) bacterial community, CH4 and CO2 emissions and SOC fractions in rice-wheat cropping system. Overall, in the wheat season following the annual rice-wheat rotation in two cycles, NT significantly increased SOC by 4.4% for 1–2 mm aggregates in the 0–5 cm soil layer, but decreased CO2 emissions by 7.4%. Compared with NS, SR notably increased the contents of SOC in the topsoil layer by 6.5% and in macro-aggregate by 17.4% in 0–5 cm soil layer, and promoted CH4 emissions (by 22.3%) and CO2 emissions (by 22.4%). The combination of NT and NS resulted in relatively high SOC and low CH4 emissions along with high bacterial community abundance. The most abundant genus under different treatments was Gp6, which significant impacted SOC and MBC. Bacterial communities like Subdivision3 had the most impact on CH4 emissions. Structural equation modeling further suggested that the soil bacterial community indirectly mediated the SOC through balancing SOC in 1–2 mm aggregates and CH4 emissions. This study provides a new idea to reveal the mechanism of short-term tillage and straw return on SOC.

The transition of natural landscapes to agricultural uses has resulted in severe loss of soil organic carbon, significantly contributing to CO2 emissions and rising global temperatures. However, soil has the largest store of terrestrial carbon (C), a considerable sink and effective strategy for climate change mitigation if managed properly. Cover crops (CC) and no-till (NT) management are two management strategies that are known to increase percent organic carbon (%OC); however, adoption of these practices has been low in the mid-South due to lack of region-specific research and resistance to unproven practices. Therefore, the purpose of this study was to evaluate the impacts of CC-NT treatments in soybean cropping systems on soil percent organic carbon (%OC) and CO2 flux following long-term implementation. Results showed significantly greater %OC in NT (1.27% ± 0.03) than reduced till (RT; 1.10% ± 0.03; p < 0.001) and greater in both CC (rye: 1.23% ± 0.03, rye + clover: 1.22% ± 0.03) than no cover (1.11% ± 0.03; p < 0.001). Bacterial abundance (p = 0.005) and pH (p = 0.006) were significant predictors of %OC. There was no overall significant difference in CO2 flux between tillage or CC treatments; however, there were significant differences between NT and RT in July of 2020 when %RH increased (p < 0.001). Bacterial abundance negatively impacted CO2 flux (p < 0.05), which contradicts most studies. The rate of proportional change and pattern of variability in C pools suggested loss of %OC in RT treatments that were not apparent when considering %OC alone. The results of this study provide valuable insight into C turnover and the effectiveness of CC use in the Mid-South to increase soil C stocks.

The effects of conservation strategies on soil organic carbon (SOC) and phosphorus (P) dynamics in dryland wheat under semi-arid temperate conditions are not well understood. This study quantified the effects of tillage and straw management on SOC concentrations and stocks and P fractions after 40 years of dryland wheat under a semi-arid temperate climate. The treatments were straw management (burned and not burned) combined with tillage methods (conventional tillage (CT), stubble mulch (SM), and no-tillage (NT)). Fertilizer nitrogen (N) and P were applied annually at 60 and 12.5 kg ha−1, respectively. The soils were sampled from 0–50, 50–200, 200–400, 400–600, 600–800, and 800–1000 mm depths, and analyzed using standard methods. The concentration of SOC was not affected by tillage and straw management, except in 200–400 mm where it was higher where the straw was burned rather than retained. The total C stock (0–1000 mm) was higher under NT with straw burning, CT with no burning, and SM, than NT with straw retention and CT with burning. In the topsoil, NT had significantly (p < 0.05) higher Bray 1 P, NaOH II Pi, and residual P than SM and CT, while burning straw increased Bray 1 P and NaHCO3 Pi concentrations. The findings imply that while the SOC concentration is not significantly affected by tillage, but is increased by burning in the subsoil only, the total C stock is improved by NT with burned straw, CT with straw retention, and SM, while the labile P fractions are increased by NT with burned straw, relative to CT with burned straw, in the semi-arid dryland wheat region.

Enhancing crop production and productivity, less energy input and reducing soil erosion make no-till (NT) an add-on choice over the conventional till (CT) system. The present study was conducted at three different locations (Beresford, Langford, and Woonsocket) to compare the natural (undisturbed) ecosystem (NE) with the tilled (CT) and no-tilled (NT) practices, and to evaluate the tillage effects on soil organic carbon (SOC) and total nitrogen (TN) contents, bulk density (ρb), enzymatic activities and aggregate stability under a corn (Zea mays L.)-soybean (Glycine max L.) cropping system. Results support that NT practices improved soil aggregation as compared to the CT and stored higher SOC and TN concentrations in the aggregates, however, NE treatment outperformed both the tillage systems. At all three sites, the NT and NE observed the lowest soil ρb than the CT soils and ranged from 1.03 to 1.49 Mg m−3. The 0–5 cm and 5–15 cm layer under NT system showed 72 and 72% higher value for β-glucosidase, 100 and 57% for acid phosphatase, respectively, compared to the CT system at Beresford site. The CT treatment significantly increased the 0.053, 0.25, and 0.5 mm aggregate size fractions at all the three sites. The NT and NE treatments had significantly higher amount of larger macroaggregates (>1 mm) for all the locations compared to the CT treatment. The SOC and TN concentrations associated with 4-mm aggregate fractions (0–10 cm depth) were significantly higher under NT than CT for Beresford, Langford, and Woonsocket (22.4, 14.6, 19.4, 14.6, 19.2, and 33.5%, respectively). Soil disturbance under CT significantly affected soil physical properties, SOC and TN concentrations, enzymatic activities and aggregate formation and stabilization. Thus, comparative evaluation with a NE concludes that tilled practices negatively affect soil properties and making a priority to adopt NT farming to enhance the soil properties in agroecosystems.

Barley (Hordeum vulgare L.) has a storied history as a food crop, and it has long been a dietary staple of peoples in temperate climates. Contemporary research studies have focused mostly on hulled barley for malt and animal feed. As such, nitrogen (N) and seeding rate agronomic data for naked food barley are lacking. In this study, we evaluated the effects of N on ß-glucan and protein content, and N and seeding rate on phenotypic characteristics of naked food barley, including grain yield, emergence, plant height, days to heading, days to maturity, test weight, percent plump kernels, and percent thin kernels. Experiments were conducted at two no-till farms, located in Almota, WA, and Genesee, ID, in the Palouse region of the Pacific Northwest from 2016 to 2018. The experiment comprised two varieties (“Havener” and “Julie”), employed N rates of 0, 62, 95, 129, and 162 kg N ha−1, and seeding rates of 250, 310, and 375 seeds/m−2. Increased N fertilization rate was shown to significantly increase all response variables, except β-glucan content of the variety Julie, days to heading, test weight, and percent plump and thin kernels. Increased N fertilization resulted in higher mean grain yield of Havener and Julie in both Almota and Genesee up to 95 kg N ha−1. Havener had higher yields (3,908 kg N ha−1) than Julie (3,099 kg N ha−1) across locations and years. Julie had higher β-glucan (8.2%) and protein (12.6%) content compared to Havener (β-glucan = 6.6%; protein = 9.1%). Our results indicate that β-glucan content is associated with genotype, environmental, and agronomic factors in dryland cropping systems of the Palouse.

The article presents the results of studies on the study the No-till technology influence depending on mineral fertilizers on the change in the agrochemical parameters of leached chernozem. Studies have shown that the seven-year use of No-till technology without fertilizers led to a decrease in the content of alkaline hydrolyzable nitrogen in leached chernozem by 10.1-13.7 mg/kg of soil, mobile phosphorus by 10.3-16.0 mg/kg, mobile potassium by 9.5-13.1 mg/kg of soil. The application of mineral fertilizers in the form of ammonium nitrate, sulfoammophos and ammophoska increased the content of alkaline hydrolysable nitrogen in the 0-30 cm layer by 12.1-13.6 mg/kg. The content of mobile phosphorus increased only in the 0-30 cm layer in the variants with the use of phosphorus-containing fertilizers by 17.7-19.9 mg/kg, and the content of mobile potassium in the variant with the potassium-containing fertilizer by 3.7-12.3 mg/kg of soil. The use of complex fertilizers such as sulfoammophos and ammofoska did not lead to a sharp decrease in pH. An increase in acidity was observed only in the variant with the use of ammonium nitrate. [ABSTRACT FROM AUTHOR]

Availability of improved tillage and herbicides during the last decades has enhanced the acceptance of conservation tillage. The main constrain to this type of tillage, particularly, zero tillage is high level of crop residue, which reduces seeding quality, soil temperature, etc. Accordingly, a study was initiated by equipping row cleaners with no-till system under wheat cultivation. For this purpose, a field experiment was laid in a split-split plot design with three types of row cleaners, three sub-treatments of travelling speed, and two subsub treatments of tillage depth. The results indicated that the soil temperature was highly affected by percent of residue left. Measurement of penetration resistance indicated that hard pan was not a potential limiting factor for the crop root development. The soil water was increased by 8.83%, 15.33% and 12.54% under no-till without row cleaner (M1), no-till with narrow row cleaner (M2) and no-till with wide row cleaner (M3) respectively compared to that under conventional tillage (CT). The percentage of soil loss reduction under M1, M2 and M3 were 53.11%, 59.62% and 50.51% compared to that under CT. The water losses were also reduced by 46.19%, 48.65% and 46.86% under these treatments as compared with CT. [ABSTRACT FROM AUTHOR]

Crop diversity, crop structures and crop residue can modify the seed-bank environment, influencing the seedling emergence of some weeds. The objectives of this work were to analyse (1) the effect of winter crop canopies of canola and wheat and soybean stubble on seedling emergence of Conyza sumatrensis and Raphanus sativus and (2) the effect of different soybean crop structures and soybean stubble on Digitaria insularis and Amaranthus palmeri seedling emergence. Two different field experiments were conducted at Buenos Aires University in a completely randomised factorial design with five replicates. The two winter species showed differences in the emergence timing whereas the two summer species emerged at the same time but with differences between years. Seedling emergence of A. palmeri was reduced by the presence of crop residue while the effect on C. sumatrensis and R. sativus emergence were more variable between years and D. insularis was not affected. Crops did not affect seedling emergence of winter species or that of A. palmeri. However, D. insularis emergence was favoured by soybean presence, mainly with closer canopy structures. Management decisions that promote the presence of crop residues favour the reduction of seedling emergence of palmer amaranth. In contrast, evaluated crop plant densities and planting dates were not able to reduce the seedling emergence of C. sumatrensis , R. sativus and D. insularis. Planting soybean in more competitive crop structures with closer canopies is not a good option due to the improvement of seedling emergence of D. insularis. Crop management decisions that inhibit seedling emergence in some species could stimulate it in others. Weeds are the greatest constraint on yields in cropping systems generating potential yield losses estimated by 43%, on a global scale. Knowledge about the relationships between agricultural practices and weed establishment is relevant for integrated weed management decisions because of variable responses of different species. Seedling emergence of four important weed species was characterised for a variety of crop management scenarios. This will help improve the success of integrated weed management and reduce the use of herbicides. [ABSTRACT FROM AUTHOR]

Our objective was to evaluate the impact of land use change, from natural forest to tillage-based systems, on the distribution of P pools and their stratification in soils under both no-till (NT) and conventionally tilled (CT) corn (Zea mays)-soybean (Glycine max) with and without cover crops, CT alfalfa (Medicago sativa), chicken and dairy manure, organic, and adjacent natural deciduous forest ecosystems (control). Results showed that residual P (RP) accounted for 68.7% followed by 13.3% calcium- and magnesium-bound P (CaMgP), 9.6% particulate organic P (POP), 8% iron- and aluminum-bound P (FeAlP), 0.3% soluble reactive P (SRP), and 0.1% exchangeable P (EP) of the total P. While the concentration of all P pools increased, the POP decreased at 0–10 cm depth under both CT and NT compared to the forest. The SRP increased threefold under NT, 2.6-fold under CT, sevenfold under alfalfa, and more than fourfold under organic, chicken and dairy manure systems. In contrast, the POP decreased by 63 to 73% under CT and 41 to 58% under NT. Likewise, the POP decreased under CT dairy and chicken manure, alfalfa, and organic systems. A similar tillage and cover crop impact on SRP and POP was observed at 10–20 cm depth. All P pools except POP have shown various degrees of stratification. An integration of cover crops under NT reduced the SRP stratification (by 41%), when compared to NT alone. Our results suggested that the SRP concentration and stratification in all agricultural systems are prone to edge-of-field loss either by drainage under NT or surface runoff under CT. [ABSTRACT FROM AUTHOR]

The aim of this work was to identify weed species in areas under different soil management systems. The research was carried out in the Brazilian Agricultural Research Corporation experimental area, in the 2017/2018 harvest, in the city of Boa Vista, Roraima State, Brazil. The experimental design was randomized blocks and the treatments included of five soil management systems (native vegetation, minimum tillage, no-tillage, conventional tillage and conventional tillage with crop rotation). Weed collection, identification, counting and drying were performed and then the phytosociological indices (Relative density, relative frequency, relative abundance, importance value index, relative importance value index and dry mass) were calculated. Variance analysis with means compared by Tukey test (P <0.05), group analysis by hierarchical and non-hierarchical method, and principal component analysis were performed. Correlation coefficients of the variables were estimated. No and minimum tillage systems had the lowest weed rates per square meter. The botanical families Poaceae, Fabaceae and Rubiaceae are the most representative in the studied systems. Concerning relative frequency, the species Cyperus flavus stood out in all treatments other than native vegetation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tillage, crop rotation, and depth have an interaction effect on K sat , λ, and FD. • NT with CS rotation increased the number of XCT-measured mesopores than RT and CT. • NT improved SOC and TN only at 0–10 cm depth in the long term (after 35 years) • Tillage effects on SOC, K sat , and mesopores were observed at subsoil. Soil hydro-physical properties and pore characteristics are crucial for crop production as they determine water, air, and nutrients transfer. Long-term tillage and crop rotation studies provide valuable insights into the effects of management practices on various soil properties. Because of the inherent differences between the surface and sub-surface soils, the impact of management systems can be pronounced differently at different soil depths. Though many studies have reported the tillage and rotation effects on soil hydro-physical properties, their vertical impacts to a depth of 40 cm were less explored. This study aims to assess the impact of long-term tillage and crop rotations on soil hydro-physical properties and pore characteristics to a depth of 40 cm utilizing the X-ray Computed Tomography (XCT) technique. Intact soil cores of 7.6 cm height × 7.6 cm ∅ were collected from tillage [no-till (NT); reduced-till (RT); conventional-till (CT)] and crop rotation [continuous corn (CC) – Zea mays L. and corn-soybean (CS) – Glycine max [Merr.] L.] plots of 0–40 cm depth (each sample for 10 cm increment). The XCT scanning allowed us to investigate the soil pore size distribution, porosity, number of branches, and average branch length. Measured hydro-physical properties in the study include bulk density (ρ b), plant available water content (PAW), saturated hydraulic conductivity (K sat), and water retention. XCT image analysis revealed that NT with CC/CS rotation increased the number of macropores at surface and sub-surface depths. However, the number of mesopores was higher with NT × CS. In addition, NT lowered the ρ b by 9.6 % and increased the PAW by 28 % compared to the CT. K sat was higher under NT × CS at 0–10 cm and had a strong positive correlation with the XCT-measured number of macropores. Therefore, we conclude that NT with CS rotation can potentially improve soil pore characteristics and hydro-physical properties, leading to enhanced soil function. [ABSTRACT FROM AUTHOR]

Soil acidity is the most limiting factor for agricultural yield and sustainability in acid soils. Liming is the management practice recommended for reducing soil acidity and increasing the availability of macronutrients, but it can also lead to reduction in the availability of cationic micronutrients when applied at high rates. The aim of this study was to evaluate the effect of application of high rates of limestone, incorporated in the 0–0.40 m soil layer, on nutrient availability and their relation to cumulative grain yield in an annual crop production system. Three experiments were set up in 2017 with six liming rates (0, 3, 6, 9, 12, and 15 Mg ha−1), with incorporation in the 0–0.40 m layer. Soil and leaf samples were collected for determination of macro- and micronutrient concentration in the leaves. Regression and linear correlation analyses were used to evaluate the effect of the application rates on the availability of nutrients and on cumulative yield in soybean, maize, dry bean (common bean) wheat crops over three crop years. The micronutrient that showed the greatest reduction in level in the soil through liming was Fe, in contrast with Zn, which was not affected. The concentrations of micronutrients in soybean and common bean leaves were more sensitive to the effect of deep liming than the levels in the soil, and reductions were observed in the concentrations of B, Fe, Mn, and Zn; however, they remained at suitable levels according to regional standards. Thus, even with the reductions in the availability of the micronutrients brought about by incorporation of higher doses of limestone (≥ 9 Mg ha−1), the cumulative grain yields showed an increase in accordance with liming rates, with the optimal dosage from 8.77 to 12.6 Mg ha−1, depending on the site. The main factors that had positive correlation with yield were soil pH and the macronutrients concentration in the leaves, which generally increased along with the liming rates. • Micronutrients availability to plants reduces with increasing limestone doses incorporated at 0.40 m. • The concentrations of macronutrients in the leaves increased with increasing limestone rates incorporated at 0.40 m. • There is a positive correlation with grain yield and soil pH and macronutrient concentration in leaves. • Accumulated grain yield increases with increasing limestone rates incorporated at 0.40 m. [ABSTRACT FROM AUTHOR]

Conservation Agriculture has been the subject of numerous studies for decades. However, its impact on the soil microbial community has often been overlooked. Recent studies have shed light on the changes in soil bacterial composition resulting from modifications in tillage practices, particularly when compared to conventional tillage methods. However, there is a lack of soil microbial community analysis conducted under conservation tillage and rainfed conditions in the Mediterranean basin. A metataxonomic approach was employed to assess the influence of 19 years (2004–2022) of minimum tillage (MT) and no-till (NT) practices, along with crop rotation, on the soil bacterial community at upper layers (15 cm depth). This field study involved three different seasonal moments throughout the year. Results revealed that both sampling time and tillage management significantly influenced the structure of the bacterial community, whereas no effect was observed due to the crop. May showed a higher taxonomic diversity than July and December, showing differences in some o fthe most abundant phyla, such as Actinobacteria, Firmicutes and Proteobacteria. On the other hand, the long-term application of NT was found to lead to a significant decrease in bacterial diversity, with lower abundances of the phyla Chloroflexi, Gemmatimonadetes, and Armatimonadota, as well as an increase in k-strategist bacteria compared to MT. However, no significant effect on alpha diversity was observed as a result of tillage. no variations in phyla composition were observed attributable to crop, as the primary distinctions were identified among legume crops, which were associated with different sampling times. Therefore, our conclusion is that over this period, NT did not promote microbial diversity in the upper soil layers, despite notable shifts in bacterial composition occurring across seasonal time points in both tillage management systems. [Display omitted] • Sampling time is a critical factor in metataxonomic analysis of soils. • Tillage management has a significant effect on soil bacterial communities. • No-tillage significantly reduces soil bacterial diversity. • No-till practices promote the enrichment k-strategist taxa of bacteria. [ABSTRACT FROM AUTHOR]

Currently, planting onion through seedling production is predominant in the state of Rio Grande do Sul. Thus, the present work aimed to evaluate the agronomic potential of new onion genotypes as a function of the planting system for this region. Eleven genotypes were evaluated, as follows: “commercial genotypes” Bola Precoce, Mulata, Sprint, Suprema and “pre-commercial genotypes” TE 201, TE 209, TE 216, TE 230, TE 242, TE 316 and TE 329, submitted to four planting systems: seedling production, seedling production with leaf pruning before transplanting, no-tillage manually planted at the definitive site and seedling production in trays. Treatments were arranged in an 11 x 4 factorial scheme (eleven genotypes and four planting systems). Although little practiced, the no-till system for onion cultivation for the northwestern region of Rio Grande do Sul can potentially be explored. Genotypes that best adapted to this system were: Bola Precoce, Suprema, Sprint, Mulata and TE 201. Comparatively, “commercial” genotypes showed an increase of 10.81 t ha-1 in relation to “pre-commercial” genotypes in the no-till system, proving the efficiency of this system.

When setting a long-term field experiment in order to study the impact of direct sowing technology on soil properties it is necessary to take into account not only the known requirements, but a comprehensive analysis of soil heterogeneity as well. The article presents the results of detailed topographic and soil-agrochemical mapping with estimation of variability of morphological and agrochemical properties of typical chernozems studied on four experimental fields of 2.4 ha area each.

The effects of tillage on soil structure, physiology and microbiota structure were studied in a long-term field experiment, with side-to-side plots, established to compare effects of conventional tillage (CT) vs no-till (NT) agriculture. After 27 years, part of the field under CT was switched to NT and vice versa. Soil texture, soil enzymatic profiles and the prokaryotic community structure (16S rRNA genes amplicon sequencing) were analyzed at two soil depths (0–5 and 5–10 cm) in samples taken 6, 18 and 30 months after switching tillage practices. Soil enzymatic activities were higher in NT than CT, and enzymatic profiles responded to the changes much earlier than the overall prokaryotic community structure. Beta diversity measurements of the prokaryotic community indicated that the levels of stratification observed in long-term NT soils were already recovered in the new NT soils 30 months after switching from CT to NT. Bacteria and Archaea OTUs that responded to NT were associated with coarse soil fraction, soil organic carbon and C cycle enzymes, while CT responders were related to fine soil fractions and S cycle enzymes. This study showed the potential of managing the soil prokaryotic community and soil health through changes in agricultural management practices. [ABSTRACT FROM AUTHOR]

Quantifying changes in soil biochemical properties is important in understanding the response to soil management practices. Our objectives were to evaluate the single and combined effects of three different crop rotations (maize (Zea mays)‐soybean (Glycine max) (2 years), maize‐soybean‐oat (Avena sativa) (3 years), maize‐soybean‐oat‐winter wheat (Triticum aestivum) (4 years)), and two winter cover‐type (cover crop and no cover crop) managements under long‐term conventional‐till (CT) and no‐till (NT) systems on water‐extractable carbon and nitrogen fractions, microbial biomass carbon (MBC) and enzymatic activities. The experimental site under silty clay loam in southeastern South Dakota was sampled before planting in early spring, after planting in early summer, and during the maize grain‐filling stage in early autumn of 2017, from the surface 0–7.5‐cm depth in 2017. In general, the cover crops had 9, 17 and 19% higher geometric mean of enzyme activities than the no‐cover‐crop plots at pre‐planting, after planting and the grain‐filling stage of maize, respectively. Although there were not many differences between "NT vs. CT" and "2‐year vs. 3‐year vs. 4‐year rotation" treatments, additive effects between "tillage and cover crops" and "rotation and cover crops" were observed. The MBC and β‐glucosidase activity were 31 and 54% higher, respectively, with cover crop vs. no cover crop under 4‐year rotation after planting of maize. Similarly, significant interactions between "cover crop and tillage" for hot water‐extractable nitrogen and urease activity at pre‐planting, and β‐D‐glucosidase after planting of maize, were observed. At the grain‐filling stage, the hot water‐extractable contents were significantly greater under cover crop as compared to the no‐cover‐crop plots. Furthermore, this study also concluded that seasonal fluctuations are important for understanding the management impacts on soil carbon fractions and biochemical properties. Highlights: Soil microbial properties responded differently to tillage, rotation and cover crops during the maize growing season.Residues produced by cover crops during winter fallow impacted soil functioning and interacted with other management factors (rotation and tillage system).Rotation impacted the carbon availability after planting, whereas tillage affected the enzyme activities.Winter cover crops influenced labile soil organic matter (SOM) and enzymatic properties after 4 years. [ABSTRACT FROM AUTHOR]

Vulpia myuros is an annual grass species of Mediterranean origin, which has achieved a global distribution. It is a fast‐growing species, with high colonisation and competitive abilities. This species is considered an invasive weed in most countries where it has been introduced, with highly negative economic impact where it now dominates. It is increasingly found to be a problematic weed in winter cereals, especially in no‐till and reduced tillage systems, across Europe, United States and Australia. Seeds of V. myuros have reduced germination potential when buried. However, where tillage interventions are reduced, ideal conditions for V. myuros are created. Minimum and no tillage practices are increasing worldwide, with a concomitant increase in the spread and abundance of V. myuros. Effectiveness of herbicides is mostly suboptimal, in particular for well‐established populations forming dense swards, even though no herbicide resistance has yet been identified. An integrated management approach, increasing crop diversification combined with management adaptations, possibly including herbicides is suggested as an effective control strategy. Despite increasing research on V. myuros, more information is needed to optimise the management of this weed. Based on the species' Mediterranean origins and adaptation to warm and dry environments, an increase of its global importance may be expected with climate changes. It is thus paramount to increase the awareness around this species, improve its identification in the field and monitor its spread before it becomes a concern of similar magnitude to grass weeds like Alopecurus myosuroides or Lolium rigidum. [ABSTRACT FROM AUTHOR]

The management of white mold (Sclerotinia sclerotiorum(Lib.) De Bary) has been one of the main production limitations faced by soybean (Glycine max L.) producers. Considering the complex management of this disease and resistance structure of the pathogen, the present study was conducted in the municipalities of Guarapuava and Palmas in Paraná with the objective of managing the white mold of soybean using straws of winter cereals, such as oat, rye, and triticale. Initially, the three winter cereals were cultivated simultaneously in both the study areas. Straw production, plant height, and shoot fresh and dry weight were evaluated. Subsequently, BMX Apollo soybean was cultivated on cereal straws, and the incidence and severity of white mold were evaluated. In the in vitro experiment, 20 sclerotia covered by a layer of cereal (oat, rye, and triticale) straws were added and carpogenic germination was observed only in the control treatment after 98 days. Regardless of the study site, rye presented greater height and fresh weight than the remaining two cereals. Soybean cultivation on winter cereal straw reduced the incidence and severity of white mold. Cultivation on rye straw reduced mold incidence by 77.7% and 76.6% in Palmas and Guarapuava, respectively. [ABSTRACT FROM AUTHOR]

Organic grain producers are interested in reducing tillage to conserve soil and decrease labor and fuel costs. We examined agronomic and economic tradeoffs associated with alternative strategies for reducing tillage frequency and intensity in a cover crop–soybean (Glycine max L. Merr.) sequence within a corn (Zea mays L.)–soybean–spelt (Triticum spelta L.) organic cropping system experiment in Pennsylvania. Tillage-based soybean production preceded by a cover crop mixture of annual ryegrass (Lolium perenne L. ssp. multiflorum), orchardgrass (Dactylis glomerata L.) and forage radish (Raphanus sativus L.) interseeded into corn grain (Z. mays L.) was compared with reduced-tillage soybean production preceded by roller-crimped cereal rye (Secale cereale L.) that was sown after corn silage. Total aboveground weed biomass did not differ between soybean production strategies. Each strategy, however, was characterized by high inter-annual variability in weed abundance. Tillage-based soybean production marginally increased grain yield by 0.28 Mg ha−1 compared with reduced-tillage soybean. A path model of soybean yield indicated that soybean stand establishment and weed biomass were primary drivers of yield, but soybean production strategy had a measurable effect on yields due to factors other than within-season weed–crop competition. Cumulative tillage frequency and intensity were quantified for each cover crop—sequence using the Soil Tillage Intensity Rating (STIR) index. The reduced-tillage soybean sequence resulted in 50% less soil disturbance compared to tillage-based soybean sequence across study years. Finally, enterprise budget comparisons showed that the reduced-tillage soybean sequence resulted in lower input costs than the tillage-based soybean sequence but was approximately $114 ha−1 less profitable because of lower average yields. [ABSTRACT FROM AUTHOR]

ABSTRACT: The management of white mold (Sclerotinia sclerotiorum(Lib.) De Bary) has been one of the main production limitations faced by soybean (Glycine max L.) producers. Considering the complex management of this disease and resistance structure of the pathogen, the present study was conducted in the municipalities of Guarapuava and Palmas in Paraná with the objective of managing the white mold of soybean using straws of winter cereals, such as oat, rye, and triticale. Initially, the three winter cereals were cultivated simultaneously in both the study areas. Straw production, plant height, and shoot fresh and dry weight were evaluated. Subsequently, BMX Apollo soybean was cultivated on cereal straws, and the incidence and severity of white mold were evaluated. In the in vitro experiment, 20 sclerotia covered by a layer of cereal (oat, rye, and triticale) straws were added and carpogenic germination was observed only in the control treatment after 98 days. Regardless of the study site, rye presented greater height and fresh weight than the remaining two cereals. Soybean cultivation on winter cereal straw reduced the incidence and severity of white mold. Cultivation on rye straw reduced mold incidence by 77.7% and 76.6% in Palmas and Guarapuava, respectively.

The production of rainfed crops in arid regions is an extremely difficult task, especially without tillage. In southern Kazakhstan, in 2020–2021, the approbation of various nutrition regimes for winter wheat grown in conditions of no-tillage rainfed lands has been studied. The effect of different doses and terms of application of growth stimulators, micronutrients, bio-fertilizers and mineral fertilizers, as well as their economic efficiency, was studied in ten variables. The use of a combination of growth stimulators and microfertilizers produced the highest grain yield and was the most cost-effective. The greatest value of the nominal net profit of 223.25 euro and 244.10 euro from one hectare was provided and calculated with the recommended target grain yield of 2.0 t/ha dose of mineral fertilizers, respectively; however, the production cost of one ton of grain in these treatments was also highest. Further research is continuing with a wider range and combination of amendments and various crops in a rainfed no-till winter wheat farm in southern Kazakhstan.

Conyza bonariensis (L.) Cronquist is a widespread noxious weed with high fecundity, associated with no-till systems such as vineyards and other perennial crops in Mediterranean climates. Seeds germinate in staggered flushes, which leads to a great variation in the growth stage between individuals in the same field, and chemical control becomes challenging. Besides, Conyza species have evolved resistance to herbicides worldwide, particularly to glyphosate. Even though tillage is expected to provide weed-free fields, it negatively affects vineyards, causing erosion, loss of soil structure and a reduction in organic matter or vine growth (shallow roots can be affected), among other effects. Fuel consumption of this management is also very high because recurrent interventions of in-row tiller are required. In this context, bioherbicides, defined as environmentally friendly natural substances intended to reduce weed populations, are a potential tool for integrated weed management (IWM). In this work, the herbicidal effect of the following six products is tested on a glyphosate-resistant C. bonariensis population present in commercial vineyards: T1, mixture of acetic acid 20% and the fertilizer N32; T2, mixture of potassium metabisulfite and pelargonic acid 31%; T3, pelargonic acid 68%; T4, humic-fulvic acid 80%; T5, hydroxy phosphate complex; and T6, potassium metabisulfite. The results showed high field efficacy for T1 and T4 (>80% biomass reduction). For the rest of the products, high efficacy was obtained only in dose–response greenhouse experiments. The present work demonstrates the potential of certain bioherbicide compounds to manage herbicide-resistant weed species, such as C. bonariensis. Therefore, bioherbicides could be successfully incorporated into vineyards for IWM.

Organic vegetable production is particularly affected by weed pressure and mechanical weeding is the major tactic implemented by growers to keep weeds under economic thresholds. Living mulch (LM) has been shown to provide several environmental services; however, LM management is required to avoid competition between service crops and cash crops. The aim of this trial was to evaluate two innovative LM-based management systems: a system that provided LM growth regulation by means of flaming (LM-FL) and a system where the LM was regularly mowed by an autonomous mower (LM-AM), both compared with a control without LM and based on standard tillage operations (TILL). The three management systems were evaluated in terms of crop production, weed control, and energy consumption on a 2 yr organic crop rotation of cauliflower (Brassica oleracea L. var botrytis) and eggplant (Solanum melongena L.). LM-AM produced an acceptable fresh marketable yield for both vegetable crops. Moreover, the weed dry biomass obtained in LM-AM-managed plots was lower compared to the LM-FL plots and ranged approximately from 200 to 300 kg ha−1. Furthermore, LM-AM management resulted in lower energy consumption (−2330 kWh ha−1 with respect to the TILL system and −7225 kWh ha−1 with respect to the LM-FL system). The results of this trial suggest that autonomous mowers have a great potential to improve LM management and help with implementing sustainable organic vegetable systems.

The productivity and quality of watermelon fruits can be influenced by several factors, edaphic or associated with cultural management, such as, the type and form of soil preparation and planting methods, which can be by direct sowing or through transplanted seedlings. The objective of this work was to evaluate productive characteristics and quality of watermelon fruits grown under different forms of soil preparation and planting methods. The experimental design used was randomized blocks, organized in a 2x3 factorial scheme, containing three replications, with 24 plants per plot. The evaluated factors were two forms of soil preparation and three forms of cultivation. The fruits were harvested when their tendrils showed visible signs of dryness, when their productive and qualitative characteristics were analyzed. The variables analyzed were the number of fruits per plant, fruit mass, transverse and longitudinal circumference of the fruits, total soluble solids (° Brix), total titratable acidity, maturation index (ratio) and total productivity. The planting methods do not alter the productive characteristics and the quality of the watermelon fruits, which proved to be adequate to the standard demanded by the national market. Conventional tillage, with plowing followed by harrowing, increases the number of fruits per plant and total productivity, reaching 30.7 Mg ha-1, a value 35.08% higher than the average for the state of Rondônia and 28.33 % above the national average. [ABSTRACT FROM AUTHOR]

The activity of 11 enzymes (catalase, dehydrogenases, peroxydases, polyphenoloxidases, ascorbateoxidase, ferrireductase, ß-fructofuranosidase, amylase, urease, phosphatase and protease) was assessed under conditions of steppe zone in the south of Russia when using different tillages. Winter wheat and sunflower are main crops in these soils. Moreover, chickpea, coriander, lint, barley, corn and some other crop are cultivated here in the crop rotation duration 6 years. Enzyme activity was compared in soils of 15 fields with long-term no-till (NT) versus to 15 fields with conventional tillage (CT). The researches were held along the whole Haplic Chernozem Loamic at a depth of 0-65 cm. Special attention was paid to top soil (0-10 cm), which is directly subject to the mechanical effect. The carbon cycle enzyme (β-fructofuranosidase) activity was the most sensitive indication for NT use. In top soil the enzyme activity was greater by 16-35% at NT versus to CT. Activity of this enzyme reduces by 28-293% when soil depth increasing in both the tillages. Enzymes of different classes had different behaviours in soils depending on season, crops and tillage thanks to biochemical nature. Hydrolases and oxidoreductases were assessed by the indices characterizing soil condition and health. For this purpose geometric mean by hydrolase activity (GMEhd) and geometric mean by oxidoreductase (GMEox), as well as integral index of biological soil condition (IIBC) were used. Index GMEox in soil under sunflower reduced by 16% in summer versus to spring. Thereby, hydrolase index GMEhd reduced by 60%. At NT activity of oxidoreductase was lower by 10 and 13%, and activity of hydrolase was increased by 12 and 14% versus to CT. Soil IIBS values at NT increased by 18-35% at average within three years (2016-2018). The use of NT technology contributes to an increase in the activity of hydrolases and soil quality due to the conservation of moisture in the soil. [ABSTRACT FROM AUTHOR]

Seasonal drought stress is common in farmland even under humid climate conditions. Low soil water content and high penetration resistance in clayey soil are both factors that limit crop growth, which is significantly affected by tillage. In a twoyear (2014-2015) field experiment conducted in Hubei, China, the effects of conventional tillage, along with occasional deep tillage and no-till, on the soil water content and penetration resistance values of red soil and on the crop water potentials of the maize crop (Zea mays L.) were tested. Compared to conventional tillage, deep tillage reduced the difference in the soil water characteristic curve between 0-40 cm soil layers, resulting in a more loose and homogeneous topsoil. The deep tillage significantly (p<0.05) decreased soil penetration resistance, increased soil-available water content and soil water content during the dry period, promoted an increase in maize root density by 11.4~31.6%, and increased the water potential of the maize root and leaf during most growth stages. In contrast, the effect of no-till was opposite to that of deep tillage, reducing maize grain yield by 25.3~26.3%. The results confirmed that no-till is not appropriate for the clayey red soil but rather that tillage is needed. This suggests that occasional deep tillage is helpful in mitigating seasonal crop drought stress under the conditions of a humid climate. [ABSTRACT FROM AUTHOR]

The effects of crop rotation and winter cover crops on soybean yield and colony-forming (CFU) units of Macrophomina phaseolina , the causal agent of charcoal rot (CR), are poorly understood. A field trial was conducted from 2011 to 2015 to evaluate (i) the impact of crop rotation consisting of soybean ( Glycine max [L.] Merr.) following cotton ( Gossypium hirsutum L.), soybean following corn ( Zea mays L.), and soybean following soybean over a 2-year rotation and its interaction with cover crop and (ii) the impact of different cover crops on a continuous soybean crop over a 5-year period. This trial was conducted in a field with 10 subsequent years of cover crop and rotation treatments. Cover crops consisted of winter wheat ( Triticum aestivum L.) and Austrian winter pea ( Pisum sativum L. subsp. sativum var. arvense ), hairy vetch ( Vicia villosa Roth), and a fallow treatment was evaluated with and without poultry litter application (bio-cover). Tissue CFU of M. phaseolina varied significantly between crop rotation treatments: plots where soybean was grown following cotton had significantly greater tissue CFU than plots following soybean. Poultry litter and hairy vetch cover cropping caused increased tissue CFU, though this effect differed by year and crop rotation treatment. Soil CFU in 2015 was substantially lower compared with 2011. However, under some crop rotation sequences, plots in the fallow treatment had significantly greater soil CFU than plots where hairy vetch and wheat was grown as a cover crop. Yield was greater in 2015 compared with 2011. There was a significant interaction of the previous crop in the rotation with year, and greater yield was observed in plots planted following cotton in the rotation in 2015 but not in 2011. The result from the continuous soybean planted over 5 years showed that there were no significant overall effects of any of the cover crop treatments nor was there interaction between cover crop treatment and year on yield. The lack of significant interaction between crop rotation and cover crop and the absence of significant differences between cover crop treatments in continuous soybean planting suggest that cover crop recommendations for midsouthern soybean growers may need to be independent of crop rotation and be based on long-term crop needs., Competing Interests: The author(s) declare no conflict of interest.

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Rollers/crimpers have been used to terminate cover crops typically with supplemental herbicide application to speed-up termination. Due to environmental concerns, there is a need to reduce herbicide use. In the Southern USA, the cash crop is typically planted three weeks after a rolled cover crop reaches more than 90% kill rate which eliminates competition with the cash crop for water and nutrients. A three-year replicated field experiment was initiated in the fall of 2014 to determine the effects of recurring rolling by experimental rollers/crimpers in terminating a cereal rye cover crop in central Alabama and how multiple rolling affected soil strength. Experimental 2-stage (one smooth drum and one crimping drum), 4-stage (one smooth drum and three crimping drums), spiral, and smooth rollers were tested to roll rye 1, 2, and 3 times (conducted at the same day). A smooth roller with mounted spray boom applying glyphosate rolling once was also evaluated, and untreated rye was the control. Rye was terminated at the milk growth stage and was evaluated one, two and three weeks after rolling. At one week after rolling, the highest rye kill rate was obtained with rolling three times by the 4-stage (96%), 2-stage (92%), spiral roller (81%); rolling once by the smooth roller with glyphosate (94%) compared to the untreated rye at 37%. At two weeks after rolling no differences among rollers were found (91% to 98%); the untreated rye was 54%. Similarly, at three weeks after rolling no differences were detected among rollers (99% to 100%); the untreated rye was 86%. Rolling 2 or 3 times compared with rolling one time did not cause soil compaction. However, at the 15 cm depth cone index (CI) did exceed 2 MPa (a critical value of root penetration restriction); although this CI increase was solely related to decrease in gravimetric soil moisture content (GMC). In addition, over three growing seasons, the seed cotton yield was not affected by rolling treatments with the average yield of 3601 kg ha-1 (1512 kg ha-1 of cotton lint). [ABSTRACT FROM AUTHOR]

Improvements in management practices can prevent the decline of soil organic carbon (SOC) storage caused by conventional tillage practice in Northeast China. Density and size fractionation can track the transformation of plant residue into SOC and its location in the soil matrix. We used a long‐term field study in China to evaluate these changes as a result of improved management involving tillage and cropping systems. Experimental treatments included no‐till (NT) and mouldboard ploughing (MP) under monoculture maize (Zea mays L.) (MM) and maize‐soybean (Glycine max Merr.) rotation (MS); these were compared to the traditional management involving conventional tillage (CT) under MM. An incubation study was conducted to evaluate mineralization and the biodegradability of SOC. The soils were also physically fractionated by density (light fraction, LF) and size (sand, silt and clay). With improved management, the SOC storage in the clay size fraction showed the largest increase across all fractions. This increase was greater for MS than MM. The NTMS treatment resulted in a decline in silt‐OC storage compared to CTMM. The SOC mineralization (mg CO2‐C g−1 soil) was affected by tillage and driven by LF‐OC and was observed in the order: NTMM (2.06) > MPMM (1.72) ≈ NTMS (1.71) > CTMM (1.52) ≈ MPMS (1.41). Both cropping and depth affected the biodegradability of SOC. Considering the plough layer (0–20 cm), treatments under MM had a larger proportion of biodegradable SOC than those under MS. We conclude that the significant differences in SOC storage in physical fractions and SOC biodegradation were caused by differences in soil management. Highlights: Clay size fraction showed the largest increase in SOC storage when residue was returned.Silt size fraction lost SOC in no‐till maize‐soybean compared with traditional farming practice.Potential SOC mineralization depended on quantity of SOC in the LF.Biodegradability of the SOC was driven by cropping system not tillage. [ABSTRACT FROM AUTHOR]

The soil-borne plant pathogens cause serious yield losses and are difficult to control. In suppressive soils, disease incidence remains low regardless of the presence of the pathogen, the host plant, and favorable environmental conditions. The potential to improve natural soil disease suppressiveness through agricultural management practices would enable sustainable and resilient crop production systems. Our aim was to study the impact of autumn tillage methods and crop sequence on the soil carbon status, fungistasis and yield in boreal climate. The disease suppression was improved by the long-term reduced and no tillage management practices with and without crop rotation. Compared to the conventional plowing, the non-inversion tillage systems were shown to change the vertical distribution of soil carbon fractions and the amount of microbial biomass by concentrating them on the soil surface. Crop sequence and the choice of tillage method had a combined effect on soil organic carbon (SOC) sequestration. The improved general disease suppression had a positive correlation with the labile carbon status and microbial biomass. From the most common Fusarium species, the predominantly saprophytic F. avenaceum was more abundant under non-inversion practice, whereas the opposite was true for the pathogenic ones. Our findings furthermore demonstrated the correlation of the soil fungistasis laboratory assay results and the prevalence of the pathogenic test fungus Fusarium culmorum on the crop cereals in the field. Our results indicate that optimized management strategies have potential to improve microbial related soil fungistasis in boreal climate.

Aim of study: Agricultural activities are the main source of volatilized ammonia (NH3). Maximum rates are reached within a few hours after slurry application. This study aimed to evaluate the influence of soil texture, tillage and slurry dry matter (DM) on NH3 volatilization. Area of study: Mediterranean semiarid environments (NE Spain). Material and methods: Ammonia volatilization from pig slurry directly applied on the soil surface was quantified in the laboratory, in soil samples from two experimental sites with different soil textures: silty loam and sandy loam. Field treatments consisted of two tillage management practices: till by disc-harrowing or no-till. At topdressing (cereal tillering), tillage treatments were combined with slurries of different DM contents applied onto the silty loam soil. Measurements were done for two cereal cropping seasons and during the period of maximum NH3 flux (12 h after slurry application). A photoacoustic analyzer was used. Main results: Slurry spreading at sowing resulted in low volatilization (0.7-9% of NH4+-N applied) as it also did at topdressing (0.3-1.4% of NH4+-N applied). At sowing, ammonia volatilization from high DM slurry (>7.5%) was significantly enhanced by no-till in both soils. At topdressing, this result was also found in records on silty loam soil. No differences were found between tillage systems when slurry of low DM content was applied, whatever the soil texture and application moment. Although NH3 volatilization was probably affected by the laboratory conditions, the comparisons between treatments were still valuable. Research highlights: Ammonia volatilization abatement can be improved (

Tillage and fertilization are common practices used to enhance soil fertility and increase yield. Changes in soil edaphic properties associated with different tillage and fertility regimes have been widely examined, yet, the microbially mediated pathways and ecological niches involved in enhancing soil fertility are poorly understood. The effects of long-term conventional tillage and no-till in parallel with three fertility treatments (No fertilization, N-only, and NPK) on soil microbial communities were investigated in a long-term field study that was established in the 1970’s. Here, we used high-throughput sequencing of bacterial, fungal and oomycetes markers, followed by community-level functional and ecological assembly to discern principles governing tillage and fertility practices’ influence on associated soil microbiomes. Both tillage and fertilizer significantly altered microbial community structure, but the tillage effect was more prominent than the fertilizer effect. Tillage significantly affected bacteria, fungi, fusaria, and oomycete beta-diversity, whereas fertilizer only affected bacteria and fungi beta-diversity. In our study different tillage and fertilizer regimes favored specific networks of metabolic pathways and distinct ecological guilds. No-till selected for beneficial microbes that translocate nutrients and resources and protect the host against pathogens. Notably, ecological guilds featuring arbuscular mycorrhizae, mycoparasites, and nematophagous fungi were favored in no-till soils, while fungal saprotrophs and plant pathogens dominated in tilled soils. Conventional till and fertilizer management shifted the communities toward fast growing competitors. Copiotrophic bacteria and fusarium species were favored under conventional tillage and in the presence of fertilizers. The analysis of the metagenomes revealed a higher abundance of predicted pathways associated with energy metabolism, translation, metabolism of cofactors and vitamins, glycan biosynthesis and nucleotide metabolism in no-till. Furthermore, no specific pathways were found to be enriched under the investigated fertilization regimes. Understanding how tillage and fertilizer management shift microbial diversity, structure and ecological niches, such as presented here, can assist with designing farming systems that can maintain high crop yield, while reducing soil erosion and nutrient losses.

Lentil (Lens culinaris Medic.) can be a potential crop to intensify the rice (Oryza sativa L.) fallow land of Tripura to meet out the pulses requirement of the state. Thus, five lentil varieties, i.e. HUL-57, WBL-77, WBL-58, PL-06 and NDL-1 were demonstrated under three establishment methods, i.e. minimum till (MT), no-till (NT) and paira cropping (PC) on 75 farmers’ field at Moracherra, Dhalai, Tripura during winter seasons of 2012–14 in a participatory mode to gear up the pulse production in the state. Study revealed that the cultivation of lentil under MT and NT systems resulted in more number of branches/plant, pods/plant, seeds/pod and seed yield than those planted under PC. Hence, the farmers planted lentil under MT obtained more gross and net returns than those planted lentil under NT and PC. However, benefit to cost (B:C) ratio was significantly higher under PC than the other establishment methods. Lentil variety HUL-57 outperformed other varieties with respect to number of branches/plant, pods/plant, seeds/pod, seed yield and also recorded the highest gross and net returns and B:C ratio followed by WBL-77, WBL-58. Therefore, study recommended the cultivation of lentil varieties HUL-57, WBL-77 and WBL-58 under minimum tillage system for intensifying the rice fallows of Tripura to boost up the pulses production in the state.

Increases in human populations and the emerging challenges of climate change mean that the world's agricultural systems will need to produce more food in an environment that is increasingly variable and where the quality of our natural resource base is declining. One central measure of an agricultural system's capacity to do this is its ability to preserve soil organic carbon (SOC), due to the pivotal role that this plays in maintaining soil physical, chemical, and biological properties and ultimately yield. This narrative review examines the literature published worldwide over the last 30 years to assess the impact of one widely applied agricultural management system, conservation agriculture (CA), on its ability to maintain SOC and the subsequent impacts on soil physical, chemical and biological properties, and yield. While the effects of CA on SOC worldwide are variable, with both increases and decreases observed, in regions where soil and climatic conditions are favorable for biomass production and where the system does not negatively impact yield, then CA can lead to higher amounts of SOC relative to conventionally managed systems, particularly in the surface of the soil profile. Where greater SOC occurs, these are also often accompanied by improvements in soil structure, water infiltration and soil water storage, plant nutrient availability, microbial biomass and diversity, and yield. However, where CA is used in certain environments (e.g., cold, wet environments with poorly drained soils) or where the CA system has not been well-adapted to local conditions, taking into account the specific agronomic, social, and environmental challenges present, then it may not be a successful system of management. Farmers require access to a range of tools and resources to allow them to identify if the principles of CA are likely to lead be appropriate for their situation and well-designed, locally adapted systems to successfully overcome the agronomic, social and economic challenges that can be associated with its use.

No-till approaches to agricultural soil management have been encouraged as a means of reducing soil erosion, reducing water pollution, and increasing carbon sequestration. An understudied additional benefit of no-till approaches may be improvements in local air quality. No-till approaches involve reductions in both machinery use and soil erosion, both of which could lead to improvements in air quality. We leverage recent advances in remote sensing and air pollution modelling to examine this question at a landscape scale. Combining data on daily PM _2.5 levels with satellite measures of no-till uptake since 2005, we show a strong association between increasing adoption of no-till and reductions in county average PM _2.5 pollution over more than 28 million hectares of cropland in the American Corn Belt. The reduction in local pollution implies substantial monetary benefits from reductions in mortality that are roughly one-fourth as large as the estimated carbon benefits. The benefits of mortality reductions are also, by themselves, nearly equal to the current monetary costs of subsidizing no-till practices.

The questions of inserting and implementing the different methods of basic soil treatment in the different crop plantings in the conditions of steppe zone in Nizhnee Povolzhye and Central Part of Non-chernozem Belt of the Russian Federation are analyzed. Systemize and complex research of the above questions are caused by multivalued opinions of agrarian scientists that are involved in the practical aspects of agrarian production towards them. On the results of long term researches is defined that the most effective and practice in cereal crop rotations are the basic soil management systems combining the different methods of tillage, mini-till and no-till soil treatment along with usage of modern machines and aggregates. In the conditions of field experiment at Centre of Precision Farming of Russian State Agrarian University - Moscow Timiryazev Agricultural Academy, along with the others, the tasks on economic efficiency and ecological safety that are the basis of precision farming concept are being solved.

The article presents a description of the main technologies of winter wheat cultivation. The conventional tillage in comparison with a no-till technology has been considered. The article gives the study results obtained by various researchers in cultivation technology of winter wheat. The authors consider both advantages and disadvantages of the conventional and no-till technologies. The main effects of the various cultivation methods on the state of soil root layer have been studied. The article presents a separate study of the aspects connected with the influence of the conventional and no-till technologies upon agrophysical properties of soil. The work considers the main reasons of erosion on the fertile soil layers and the effect of tillage on prevention of these processes. The authors present the data about the effect of various tillage methods on the infection of winter wheat by pests and on weeds distribution.

The article substantiates the necessity to define and generalize the criteria for assessing the ecological and economic efficiency of using agricultural lands. Due to the transition of the agro-industrial complex to private forms of management, the problems of forming a strategy of rational, ecologically safe and sustainable development of land use in Ukrainian agriculture became of paramount importance. Therefore, systematic studies on the assessment of the ecological and economic efficiency of the agricultural land use need to be conducted. Harmonization of ecological and economic interests is of particular importance in the context of ensuring the conservation, resource-saving and reproductive nature of the agricultural land exploitation.A scientific study found that in Ukraine, the agrarian sector of the economy provides about 47% of GDP, but the question arises: At what price are these achievements given to us? Agricultural land development exceeds environmentally sound standards. Excessive cultivation of the territory leads to an annual increase of eroded lands by 80-90 thousand hectares. Land use is recognized as environmentally unstable, and there is a steady tendency to deteriorate the quality of soil. Each second hectare of cultivated land is erosion-hazardous, that is, these soils are subject to water and wind erosion. In this regard, it is recommended to introduce the world-wide experience of Climate Smart Agriculture (CSA), which provides an opportunity to provide food security to the country and to limit the negative impact of the environment, based on the introduction of organic production.It is proved that regardless of the size of farms and forms of management using resource-saving no-till technologies, enterprises received low cost of grown products, providing profitable activities. Ecological compatibility of the technology provides energy savings of at least 30% in comparison with traditional farming systems, the accumulation of not less than 30-40% of plant residues on the soil surface after harvesting of the predecessor, provides protection of the soil from wind and water erosion by minimizing the amount and depth of technological operations.It is confirmed that the most widespread evaluation of the agricultural lands use is the evaluation of the results of their use through volumes of gross and commodity products, income, and production profitability. The criteria for the environmental effectiveness of agricultural land use should be: the degree of functional use of land resources, ecological stability, the level of anthropogenic loading, the degree of erosional feature of land, etc.According to the study results, it was established that one of the main areas of agriculture is the application of minimal tillage in crop rotation, i.e. resource-saving no-till technology.The economic feasibility of technologies based on the use of different soil tillage systems has been confirmed.