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Cover crops and nitrogen (N) fertilization may affect soil mineral N, N uptake, and N productivity (grain yield per unit plant available N) in wheat (Triticum aestivum L.). We evaluated the effect of summer cover crops and N fertilization rates on soil mineral N and winter wheat grain yield, N uptake, and N productivity in the Loess Plateau of China. We measured cover crop aboveground biomass N, soil mineral N (0-20 cm), and winter wheat yield, N uptake, and N productivity for four seasons from 2017-2018 to 2020-2021. Cover crops were soybean (Glycine max L., SB), sudangrass (Sorghum sudanense [Piper] Stapf, SG], soybean and sudangrass mixture (SS), and no cover crop (CK) and N fertilization rates were 0, 60, and 120 kg N ha−1 applied to wheat. The SB increased cover crop biomass N and soil mineral N by 15 to 65%, but SS increased winter wheat yield, protein concentration, and N uptake by 25 to 55% compared to SG and CK at most N fertilization rates and years. Nitrogen fertilization rate had a variable effect on cover crop and wheat parameters. Wheat N productivity was 55 to 85% greater with CK than cover crops, but decreased with increased N fertilization rates. The N fertilizer equivalence of cover crops for wheat yield and N uptake ranged from 31 kg N ha−1 for SG to 150 kg N ha−1 for SS. Overall, SS with 60 kg N ha−1 can sustain winter wheat N uptake and N productivity compared to SG or CK with or without N fertilization. [ABSTRACT FROM AUTHOR]

ABSTRACT Background Aims Methods Results Conclusion The direct effect of winter cover crops (WCCs) or living mulches (LMs) on a first vegetable crop has already been investigated. However, little is known about the effect on growth and yield of a second cash crop in the rotation.The aim of the study was to assess the carry‐over effect of legumes grown as WCC or LM on winter wheat as a second crop after cabbage, measured in yield and nitrogen release.Two field trials were carried out in Germany between 2019 and 2022. In the WCC trial, rye, rye with vetch, vetch, pea, and faba bean were used as WCC and compared to bare soil. The WCC biomass was incorporated before cabbage planting in late spring. For the LM trial, perennial ryegrass or white clover was used as LM during cabbage cultivation and compared to bare soil. The LM biomass was incorporated with the cabbage residues and compared to an early incorporation of LM biomass before cabbage planting. In both trials, winter wheat was sown in the fall as the second following main crop in the rotation.Leguminous WCC species had significant higher wheat yield compared to non‐legumes but not compared to the control without WCC. Late incorporation of LM biomass resulted in increased wheat yield at 10.1–10.4 Mg ha−1 compared to an early incorporation before cabbage planting at 9.35 Mg ha−1. Net N releases show that for WCC, the main effect of legume nitrogen fixation is achieved in the first crop cabbage immediately after incorporation of WCC biomass. In the case of leguminous LM, the effects of legume nitrogen fixation are of much higher relevance in the second main crop, winter wheat, due to LM biomass incorporation after cabbage cultivation.Therefore, we suggest to consider not only the direct but also the carry‐over effects of leguminous cover cropping in vegetable crop rotations. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effects of winter cover crops (CCs) on soybean agronomic performance and their implications for different physiological groups of rhizosphere microorganisms in two sustainable production systems. The production techniques for rye, peas, and oats are well known, but their suitability as CCs for soybean (organic and low-input) production needs to be examined. After two years of trials, soybean yields among the two tested winter CCs (peas and oats (P + O) and rye (R)) were statistically significant only for P + O. The soybean yield in succession to P + O as winter CCs was 3.0 t ha−1, whereas in succession to R, it was 2.7 t ha−1, and in the control plot, it was 2.6 t ha−1. The average soybean grain protein content was in the range of 40 to 41% dry matter (DM), while the oil content ranged from 20 to 22% DM. Protein and oil content primarily depends on the selected soybean variety and it is confirmed through this study that, in the studied system, we can obtain adequate grain nutritional quality. The results indicate an increase in the abundance of total bacteria, ammonifiers, and free N2-fixing bacteria in the rhizosphere, depending on the selected CCs, and differences between the tested production systems. According to this study, winter cover crops (CCs), including peas and oats (P + O) and rye (R), can be included in crop rotation for soybean. CCs can be the answer to agro-biodiversity empowerment in less diverse soybean cropping systems, along with other benefits that CCs can provide at the level of crop rotation. In addition, in almost all aspects of the study, organic production was ahead of low input. Low input is an adequate production system if there are no opportunities for organic certification and for producers who are aware of the advantages of sustainable systems, and it can also represent a transitional path towards regenerative agriculture or organic production. [ABSTRACT FROM AUTHOR]

Summary Cover crop integration into grain crop rotations is a promising strategy for mitigating nematode‐induced diseases in agriculture. However, the precise mechanisms underlying this phenomenon remain elusive. Here, we first assessed the impact of five commonly used cover crops on the suppression of rice root‐knot nematodes (RKNs). We then chose ryegrass as a model to explore the mechanistic basis of the suppression effect. Contrary to expectations, while ryegrass rotation significantly enhances soil fertility, this increased fertility has minimal impact on RKN suppression. Furthermore, neither integrated ryegrass residues nor root exudates exhibit direct toxicity towards RKNs. We demonstrated that ryegrass rotation primarily suppresses RKNs by enriching beneficial soil microbiota. By complementing with isolated bacteria strains, we further demonstrated that ryegrass‐enriched bacteria not only directly reduce RKN infectivity and preference, but also activate plant immunity via the OsLRR‐RLK‐MAPK‐WRKY‐JA cascade, thereby diminishing RKN infection. Our study highlights the crucial role of soil microbiota in plant–nematode interactions, challenging conventional views on the direct effects of cover crops in nematode suppression. It offers a mechanistic understanding of the regulation potential and action modes of cover crops in mitigating nematode diseases, providing valuable insights for sustainable agriculture. [ABSTRACT FROM AUTHOR]

AbstractThis study compared the weed suppression ability of a native cover crop species phacelia (Phacelia tanacetifolia), an introduced cover crop species rye (Secale cereale L.), and a no cover crop (herbicide‑managed) system in a vineyard. Cover crops were sown in the interrow spaces of the grapevine rows. Percent weed cover after the cover crop termination was lower in the interrow of the phacelia than the no cover crop plots. During the cover crop growing season, phacelia suppressed weeds more than rye. However, the weed seedbank of the cover crop plots was greater than that of the no cover crop plots. [ABSTRACT FROM AUTHOR]

Cover crops are multifunctional tools that mitigate environmental impacts of agriculture, enhance resilience to weather extremes and suppress weeds and arthropod pests. Cover crops provide non‐crop food and habitat resources that attract natural enemies of pests, but their outcomes for pest management are less clear in regions where keystone mutualisms between red imported fire ants and aphids dominate. Here, we manipulate ant exclusion treatments and cover crop treatments (living mulches and terminated cover crops) that vary in food/habitat resources and examine responses of ants, aphids, other herbivores and predators in a cotton agroecosystem. Living mulches reduced both ants and aphids in the crop canopy by 97% and 93%, respectively, relative to bare soil treatments, and terminated cover crops reduced them as well by a lesser degree (~50%). Non‐aphid herbivores occurred in low densities system‐wide and increased in living mulches, whilst native predators had variable responses to cover crops and ant exclusion. Cover crops had no effect on prey removal in the crop canopy, but living mulches tripled rates of weed seed biocontrol, relative to bare soils. Cover crops elicited a shift in fire ant foraging from cotton foliage downward to the soil‐surface, preventing competitive exclusion by keystone ant/aphid mutualists that dominate crop monocultures. Cover crops altered the system‐wide impacts of fire ants: reducing ecosystem disservices (i.e. aphid tending) and enhancing ecosystem services (i.e. weed seed biocontrol). These results provide incentives for cover crop adoption as a regenerative practice in large‐scale commercial agriculture. [ABSTRACT FROM AUTHOR]

Cotton cultivation in the United States is relevant globally, with the nation ranking among the top producers and exporters. This study examines conservation practice adoption trends and technological advancements in U.S. cotton production, focusing on sustainability and productivity. Efforts to improve cotton farming practices have reduced its environmental impacts, including decreased soil loss, water usage, and greenhouse gas emissions. Precision agriculture technologies have been instrumental in enhancing efficiency and reducing input costs, albeit with varying degrees of success. To gain deeper insights into cotton grower challenges and needs, a Natural Resource Survey was conducted in 2023 with 753 respondents. As a follow-up to the 2008 and 2015 surveys, the insights from this survey provide valuable data on grower practices and priorities, highlighting the increasing influence of climate change on cotton production. The findings underscore the importance of conservation agriculture and ongoing research to address grower concerns while improving production efficiency. Particularly noteworthy are the outcomes indicating an increase in cover crop adoption and a decrease in tillage practices, reflecting the industry's commitment to sustainability. This study contributes to understanding the dynamics shaping the U.S. cotton industry and offers insights into the challenges and opportunities for continual improvement in U.S. cotton cultivation. [ABSTRACT FROM AUTHOR]

The document "Soil Health and Crop Management in Conservation Agriculture" discusses the importance of conservation agriculture in addressing global food production challenges while maintaining soil health. Conservation practices like minimum tillage and crop diversification have shown to enhance soil aggregation, biological activity, water retention, and nutrient cycling. Various studies highlighted in the document demonstrate the positive impact of practices such as biochar application, cover crops, and advanced tillage methods on soil fertility, crop yield, and environmental sustainability. Overall, the research emphasizes the potential of conservation agriculture to create resilient and productive farming systems for a sustainable food future. [Extracted from the article]

This work was conducted over three-year monitoring seasons of three almond cultivars (Guara, Marta, and Lauranne) subjected to deficit irrigation in combination with cover crops in a Mediterranean semiarid area (SW, Spain). Four water–soil treatments were evaluated based on the conjunction of two irrigation strategies: fully irrigated (FI), covering 100% of the ETC, and regulated deficit irrigation (RDI), with two soil-management systems: bare soil (BS) and cover crop based on a mixture of vetch (Vicia sativa L.) and oat (Avena sativa L.) (CC). Throughout the study period in trees, the yield, the stem water potential (Ψstem), leaf nutrient content (N, P, K, Ca, Mg, Na, Fe, Zn, Mn, and Cu) in soils, organic carbon, microbial biomass, fluoresceine diacetate, and enzymatic activities (dehydrogenase, protease, β-glucosidase, and alkaline phosphatase) were determined. In addition, the dry matter and carbon fixation by plant covers were evaluated. For Guara and Lauranne, yield reductions (22 and 26%, respectively) were found for water-stressed (RDI-CC) plots with respect to non-stressed combination (FI-CC) plots, contrasting with cv. Marta, without a significant impact on productivity in all combinations. That is, the RDI (~3.000 m3 ha−1) strategy enabled acceptable productivity, offering promising possibilities for cultivation performance under water-scarcity scenarios. Important differences in Ψstem could be observed and ascribed to irrigation strategies, especially for Guara and Lauranne, but without significant effects due to the soil-management systems applied. No differences were observed in the tree nutritional status due to the presence or absence of CC; however, its presence increased the fixation of atmospheric carbon, which was not the case under BS conditions. Additionally, CC significantly fostered the microbial processes and enzymatic activities, particularly in upper soil layers (0–10 cm) and with plenty of water supply in FI-CC plots and to a lesser extent in RDI-CC plots, which could encourage prominent aspects for soil quality and health restoration. Thus, the cover crop is congruent with RDI to facilitate soil functionality and water savings in a changing climate, contributing to resilient farming systems in the Mediterranean environment. [ABSTRACT FROM AUTHOR]

Cover cropping consists in sowing non-cash crops to improve regulating and supporting services without seeking provisioning services. Cover cropping has the potential for spatio-temporal diversification of cropping systems to help address food security while also improving environmental sustainability. However, cover crops are still poorly adopted by farmers worldwide. One of the key reasons behind this poor adoption is the difficulties in ensuring cover crop establishment that is further exacerbated by the current knowledge gaps. On the other hand, no study has yet summarized key published and unpublished information on cover crop emergence and field establishment that may help fill these knowledge gaps. In light of this, for the first time, we comprehensively review the literature to summarize and quantify information related to cover crop emergence and propose strategies for improving their field establishment. The major findings are as follows. (1) Detailed statistics on the share of arable land sown to cover crops are lacking, but the available information suggests that this share is increasing over the years ranging from 4% in the USA to 9% in the EU. (2) Four key factors—regulations and public policy incentives, economic factors, knowledge factors, and environmental factors—influence the adoption or non-adoption of cover crops by farmers. (3) Poor emergence and field establishment, due to unfavorable environmental conditions, is one of the most important obstacles to cover crop adoption across temperate regions worldwide. (4) Five forms of cover crop sowing are practiced by farmers that can be grouped into two major sowing strategies—sowing before and after harvesting cash crops—each of them presenting several strengths and limits. (5) A wide range of sowing equipment is available for farmers but their choice depends on several factors including work output and costs. Finally, we emphasize the role of a decision support system and modeling, for an optimal cover crop sowing and field establishment, which are key for enhanced quantity of biomass production and ecosystem service provisioning. [ABSTRACT FROM AUTHOR]

Purpose: Cover crops and reduced tillage are two key climate smart agricultural practices that can provide agroecosystem services including improved soil health, increased soil carbon sequestration, and reduced fertilizer needs. Crop residue carbon traits (i.e., lignin, holocellulose, non-structural carbohydrates) and nitrogen concentrations largely mediate decomposition rates and amount of plant-available nitrogen accessible to cash crops and determine soil carbon residence time. Non-destructive approaches to quantify these important traits are possible using spectroscopy. Methods: The objective of this study was to evaluate the efficacy of spectroscopy instruments to quantify crop residue biochemical traits in cover crop agriculture systems using partial least squares regression models and a combination of (1) the band equivalent reflectance (BER) of the PRecursore IperSpettrale della Missione Applicativa (PRISMA) imaging spectroscopy sensor derived from laboratory collected Analytical Spectral Devices (ASD) spectra (n = 296) of 11 cover crop species and three cash crop species, and (2) spaceborne PRISMA imagery that coincided with destructive crop residue collections in the spring of 2022 (n = 65). Spectral range was constrained to 1200 to 2400 nm to reduce the likelihood of confounding relationships in wavelengths sensitive to plant pigments or those related to canopy structure for both analytical approaches. Results: Models using laboratory BER of PRISMA all demonstrated high accuracies and low errors for estimation of nitrogen and carbon traits (adj. R2 = 0.86 − 0.98; RMSE = 0.24 − 4.25%) and results indicate that a single model may be used for a given trait across all species. Models using spaceborne imaging spectroscopy demonstrated that crop residue carbon traits can be successfully estimated using PRISMA imagery (adj. R2 = 0.65 − 0.75; RMSE = 2.71 − 4.16%). We found moderate relationships between nitrogen concentration and PRISMA imagery (adj. R2 = 0.52; RMSE = 0.25%), which is partly related to the range of nitrogen in these senesced crop residues (0.38–1.85%). PRISMA imagery models were also influenced by atmospheric absorption, variability in surface moisture content, and some presence of green vegetation. Conclusion: As spaceborne imaging spectroscopy data become more widely available from upcoming missions, crop residue trait estimates could be regularly generated and integrated into decision support tools to calculate decomposition rates and associated nitrogen credits to inform precision field management, as well as to enable measurement, monitoring, reporting, and verification of net carbon benefits from climate smart agricultural practice adoption in an emerging carbon marketplace. [ABSTRACT FROM AUTHOR]

Information is required to understand how novel biodiversity strategies can improve cropping system resilience to climate change. A "business as usual" (BAU) rotation (wheat–canola–wheat–soybean) was compared with a "warm-season crop" (WS) rotation (corn–sunflower–dry bean–canola); a "biodiverse" (BD) rotation (fall rye with cover crop– corn/soybean intercrop—pea/canola intercrop–green fallow mixture); a "perennial grain" (Kernza) rotation (Kernza grain intermediate wheatgrass); and an organic (ORG) rotation (millet-green fallow mixture-wheat). Drought conditions prevailed in both study years. The BAU rotation had the lowest average yield (1821 kg ha−1 compared with 2533 and 3083 kg ha−1 for the BD and WS rotations, respectively), less post-harvest residual biomass, and a lower net return than the WS rotation. The WS rotation was limited by herbicide-resistant weeds in dry beans. Kernza seed yield was five times lower than for spring wheat. ORG wheat yielded the same as other wheat and had a higher net return. Live roots days, a measure of soil health potential, were 95 for the BAU rotation and 174 and 113 for the BD and WS rotations, respectively; the most were recorded for Kernza (365). Seasonal crop growth duration was increased by including Kernza and fall rye for early season growth, and corn, sunflower, a corn–soybean intercrop, a cover crop, and fall-seeded rye for late season growth. WS and BD rotations outperformed the BAU rotation and the BD system accomplished this with half the N fertilizer. Results demonstrate the potential of biodiverse rotations; barriers to their adoption should be addressed. [ABSTRACT FROM AUTHOR]

Intercropping to integrate cover crops with fruit trees in the Brazilian Cerrado is an innovative strategy for creating a more sustainable food system. This agricultural practice contributes to maintaining soil quality and improves fruits' chemical and technological properties, such as those of Eugenia dysenterica (Mart.) DC. (cagaita). Given the significant fruit production potential of the Brazilian Cerrado, this study aimed to investigate the impact of an intercropping system involving cagaita trees and various cover crops, specifically Calopogonium mucunoides Desv. (CA), Crotalaria juncea (CR), Lablab purpureus (L.) Sweet (LA), brachiaria (Brachiaria decumbens L.) + nitrogen source (urea) (BRN), and brachiaria (Brachiaria decumbens L.) (BR), on the chemical composition, technological properties, and morphological characteristics of cagaita fruits. Treatments involving leguminous cover crops (CA, LA, and CR) significantly increased nitrogen (N) levels in cagaita fruits, comparable to those observed with the BRN treatment. However, the treatment utilizing BR resulted in the highest levels of macrominerals (Ca, Mg, and K), which are essential for meeting the Recommended Dietary Intake (RDI) and demonstrated a notable positive impact on pulp yield (>78%). Additionally, the antioxidant potential and phenolic content were the highest in the BR, CA, and LA treatments, with the lowest levels recorded for the CR treatment. This study underscores the importance of sustainable agricultural practices in the Brazilian Cerrado, demonstrating their potential to enhance the nutritional quality (both micro and macronutrients), technological properties, and overall development of Eugenia dysenterica DC. fruits, thereby adding value to food and contributing to a more resilient and productive food system. [ABSTRACT FROM AUTHOR]

The adoption of conservation agriculture methods, such as conservation tillage and cover cropping, is a viable alternative to conventional farming practices for improving soil health and reducing soil carbon losses. Despite their significance in mitigating climate change, there are very few studies that have assessed the overall spatial distribution of cover crops and tillage practices based on the farm's pedoclimatic and topographic characteristics. Hence, the primary objective of this study was to use multiple satellite-derived indices and environmental drivers to infer the level of tillage intensity and identify the presence of cover crops in eastern South Dakota (SD). We used a machine learning classifier trained with in situ field samples and environmental drivers acquired from different remote sensing datasets for 2022 and 2023 to map the conservation agriculture practices. Our classification accuracies (>80%) indicate that the employed satellite spectral indices and environmental variables could successfully detect the presence of cover crops and the tillage intensity in the study region. Our analysis revealed that 4% of the corn (Zea mays) and soybean (Glycine max) fields in eastern SD had a cover crop during either the fall of 2022 or the spring of 2023. We also found that environmental factors, specifically seasonal precipitation, growing degree days, and surface texture, significantly impacted the use of conservation practices. The methods developed through this research may provide a viable means for tracking and documenting farmers' agricultural management techniques. Our study contributes to developing a measurement, reporting, and verification (MRV) solution that could help used to monitor various climate-smart agricultural practices. [ABSTRACT FROM AUTHOR]

There is increasing adoption of winter cover crops (WCCs) in corn and soybean production in Canada, primarily to reduce erosion and increase soil organic matter content. WCCs have the potential to influence nematode communities by increasing free-living nematodes and decreasing plant-parasitic nematodes or vice versa. However, the mechanism by which WCCs change nematode community assemblages still remains a key question in soil food web ecology. We tested the hypothesis that the long-term use of rye (Secale cereale), barley (Hordeum vulgare) and oat (Avena sativa) as monocultures or mixtures promotes nematode communities and improves overall soil health conditions compared to winter fallow. The results from this study revealed that the use of WCCs generally promoted a higher abundance and diversity of nematode communities, whereas plant parasitic nematodes were the most abundant in winter fallow. Moreover, the mixtures of WCCs had more similar nematode communities compared to rye alone and winter fallow. The structure and enrichment indices were higher with WCCs, indicating higher nutrient cycling and soil suppressiveness, which are signs of healthy soil conditions. Furthermore, WCCs significantly reduced the populations of root lesion nematode Pratylenchus, although their numbers recovered and increased during the main crop stages. Additionally, mixtures of WCCs promoted the highest abundance of the stunt nematode Tylenchorhynchus, whereas winter fallow had a higher abundance of the spiral nematode Helicotylenchus during the fallow period and the main crop stages. The results show that the long-term use of cover crops can have a positive impact on nematode communities and the soil food web, but these changes depend on the type of WCCs and how they are used. [ABSTRACT FROM AUTHOR]

Background: Cover cropping is an agricultural practice that uses secondary crops to support the growth of primary crops through various mechanisms including erosion control, weed suppression, nutrient management, and enhanced biodiversity. Cover crops may elicit some of these ecosystem services through chemical interactions with the soil microbiome via root exudation, or the release of plant metabolites from roots. Phytohormones are one metabolite type exuded by plants that activate the rhizosphere microbiome, yet managing this chemical interaction remains an untapped mechanism for optimizing plant-soil-microbiome interactions. Currently, there is limited understanding on the diversity of cover crop phytohormone root exudation patterns and our aim was to understand how phytochemical signals selectively enrich specific microbial taxa and functionalities in agricultural soils. Results: Here, we link variability in cover crop root exudate composition to changes in soil microbiome functionality. Exudate chemical profiles from 4 cover crop species (Sorghum bicolor, Vicia villosa, Brassica napus, and Secale cereal) were used as the chemical inputs to decipher microbial responses. These distinct exudate profiles, along with a no exudate control, were amended to agricultural soil microcosms with microbial responses tracked over time using metabolomes and genome-resolved metatranscriptomes. Our findings illustrated microbial metabolic patterns were unique in response to cover crop exudate inputs over time, particularly by sorghum and cereal rye amended microcosms. In these microcosms, we identify novel microbial members (at the genera and family level) who produced IAA and GA4 over time. Additionally, we identified cover crop exudates exclusively enriched for bacterial nitrite oxidizers, while control microcosms were discriminated for nitrogen transport, mineralization, and assimilation, highlighting distinct changes in microbial nitrogen cycling in response to chemical inputs. Conclusions: We highlight that root exudate amendments alter microbial community function (i.e., N cycling) and microbial phytohormone metabolisms, particularly in response to root exudates isolated from cereal rye and sorghum plants. Additionally, we constructed a soil microbial genomic catalog of microorganisms responding to commonly used cover crops, a public resource for agriculturally relevant microbes. Many of our exudate-stimulated microorganisms are representatives from poorly characterized or novel taxa, revealing the yet to be discovered metabolic reservoir harbored in agricultural soils. Our findings emphasize the tractability of high-resolution multi-omics approaches to investigate processes relevant for agricultural soils, opening the possibility of targeting specific soil biogeochemical outcomes through biological precision agricultural practices that use cover crops and the microbiome as levers for enhanced crop production. BPG5Z_iDvqR4KrAs2TcSTi Video Abstract [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTThe effectiveness of phytoremediation in Cd-contaminated soils is crucial for enhancing nutrient availability and plant tolerance to Cd. We simulated soil contamination with varying textures and fertilization conditions. Two experiments were conducted: one without liming and fertilization and another with soil fertilization for grasses. The soil types used were Oxisol and Entisol, and the grasses tested were Megathyrsus maximus and Urochloa brizantha at three Cd levels: 0 mg kg−1 (Control), 2 mg kg−1 (Low), and 12 mg kg−1 (High). Soil amendments and fertilization did not significantly change Cd availability. Soil chemical attributes were unaffected by Cd contamination but were influenced by fertilization, which kept the pH below optimal levels. Cd availability was higher in more contaminated soils, with Entisol showing greater concentrations than Oxisol. Dry matter production of the grasses decreased with higher contamination, with U. brizantha being more productive than M. maximus in fertilized soils. Cd accumulation was higher in highly contaminated soils, particularly for U. brizantha. The bioconcentration factor was higher in Entisol, while the translocation factor exceeded 1.0 only for M. maximus in low-contamination Oxisol. Fertilization can mitigate Cd contamination effects, with U. brizantha showing greater tolerance and accumulation capacity in fertilized soils.Grasses, often seen just as cover crops or forages, can play a vital role in mitigating heavy metal pollution, especially Cd. By comparing the growth, Cd accumulation, and tolerance of different grass species in fertilized versus unfertilized soils, we identify optimal strategies to maximize the effectiveness of phytoremediation without compromising soil health and ecological balance. The findings of the study reveal that the response of grasses to fertilization in contaminated soils varies significantly, directly influencing their capacity to phytoremediate Cd. This discovery suggests that customizing fertilizer use, based on the grass species and specific soil conditions, could be crucial for optimizing the removal of Cd from the environment. [ABSTRACT FROM AUTHOR]

AbstractSoil cover biomass in integrated systems can improve agronomic characteristics and impact in soybean productivity. Thus, the objective is to evaluate the desiccation efficiency, biomass production, nutrient accumulation, and soybean productivity in Quênia guinea grass (Panicum maximum cv. BRS Quênia) biomass after with an intercropped with maize in different forms of seeding, in compare the conventional soybean. The experimental design was a randomized block with four replicates. The treatments consisted of cover crop biomass: maize monoculture; Quênia guinea grass monoculture; maize intercropped with Quênia guinea grass within rows; maize intercropped with Quênia guinea grass between rows and an additional soybean treatment without cover biomass. The results showed that the Quênia guinea grass in the different cropping systems presented high desiccation efficiency, showing potential as a cover plant in integrated systems. The intercropping system of maize with Quênia guinea grass between rows is more recommended than seeding in the same rows as maize, because it promotes greater biomass production and nutrient cycling, reflecting in higher soybean productivity. The integrated production systems is a promising and efficient technology for production systems compared to the system of monoculture maize and soybeans without soil cover biomass, which ensures greater sustainability of agricultural systems. [ABSTRACT FROM AUTHOR]

Despite the well documented link between cover cropping and soil microbiology, the influence of specific cover crop species on soil microbes remains poorly understood. We evaluated how soil fungal communities in a no till system respond to four cover crop treatments: no cover crop (REF), cereal ryegrass (CRYE), wild pennycress (WPEN), and a mix of pea, clover, radish, and oat (PCRO). Soil samples were collected from experimental plots following termination of cover crops from depths of 0–2 cm and 2–4 cm where cover crops had significantly increased soil organic matter. There was no significant interaction between soil depth and cover crop treatment on either alpha diversity or beta diversity. All cover crop treatments (CRYE, PCRO, and WPEN) enhanced soil fungal richness but only CRYE enhanced soil fungal diversity and altered the fungal community structure. Soil depth altered the fungal community structure but had no effect on fungal diversity and richness. Genus Fusarium which includes some of the most economically destructive pathogens was more abundant in REF and PCRO treatments compared to CRYE and WPEN. In contrast, genus Mortierella which is known to promote plant health was more abundant in all cover crop treatments relative to the REF. These findings demonstrate that cover cropping can increase soil fungal species richness and alter fungal community structure, potentially promoting the abundance of beneficial fungi and reducing the abundance of some plant pathogens within the genus Fusarium. These effects are dependent on cover crop species, a factor that should be considered when selecting appropriate cover crops for a particular cropping system. [ABSTRACT FROM AUTHOR]

Cover crops, a soil conservation practice, can contribute to reducing disease pressure caused by Pseudomonas syringae, considered one of the most important bacterial plant pathogens. We recently demonstrated that the phyllosphere (leaf surface) bacterial community structure changed when squash (Cucurbita pepo) was grown with a rye (Secale cereale) cover crop treatment, followed by a decrease of angular leaf spot disease symptoms on squash caused by P. syringae pv. lachrymans. Application of biocontrol agents is a known agricultural practice to mitigate crop losses due to microbial disease. In this study, we tested the hypothesis that some phyllosphere bacteria promoted when squash is grown on cover crops could be isolated and used as a biocontrol agent to decrease angular leaf spot symptoms. We grew squash during a 2-year field experiment using four agricultural practices: bare soil, cover crops, chemically terminated cover crops, and plastic cover. We sampled squash leaves at three different dates each year and constructed a collection of cultivable bacterial strains isolated from squash leaves and rye cover crop material. Each isolated strain was identified by 16S rRNA gene sequencing and used in in vitro (Petri dish) pathogen growth and in vivo (greenhouse) symptom control assays. Four bacterial isolates belonging to the genera Pseudarthrobacter, Pseudomonas, Delftia, and Rhizobium were shown to inhibit P. syringae pv. lachrymans growth and angular leaf spot symptom development. Strikingly, the symptom control efficacy of all strains was stronger on older leaves. This study sheds light on the importance of bacterial isolation from cover crop sources to promote disease control. [ABSTRACT FROM AUTHOR]

Growing cover crops promotes soil health as they retain nutrients during autumn/winter and provide organic matter to the soil biota, which in turn supplies nutrients to the main crop upon mineralisation in spring. Different cover crops have varying impacts on soil biology and nutrient dynamics due to the quantity and quality of plant material returned to the soil. To understand these effects, high‐resolution data on crop responses is required. In this study, remote sensing was used to provide such data. The temporal dynamics of soil nitrogen (N) availability and N uptake in barley were studied in response to different cover crop monocultures and mixtures. This was achieved using high‐resolution multispectral images of the main crop acquired from an unmanned aerial vehicle. Alongside this, in‐situ collected plant and soil parameters were used in this 5‐year cover crop field experiment. The results showed that cover crop legacies significantly affected barley N uptake, biomass, and canopy N content. In early June, at peak canopy N, the highest values were observed in barley grown after vetch‐radish or oat‐radish mixtures (84 kg N/ha) and the lowest in barley grown after fallow (63 kg N) or oat (53 kg N/ha on 23rd of June). At the start of the barley growing season, soil microbial biomass was not significantly affected by the cover crop legacies. However, differential N mineralisation between cover crop legacies can be attributed to differences in microbial activity associated with cover crop quantity and quality. This research demonstrates the potential of remote sensing to monitor and understand temporal and spatial variation of crop canopy N in response to cover crop N mineralisation by the soil biota which is an important component of soil health. This approach can contribute to more efficient N use by enabling fine‐tuning of the type, quantity, timing, and location of fertilisation. [ABSTRACT FROM AUTHOR]

The aim of this review was to collect current results on the effect of different plants grown as winter and summer cover crops (CC) on the physical, chemical, and biological properties of soil and on the yield of cereal crops grown in a site with CC, using conservation soil tillage. The analyzed studies indicate that CC usually have a positive impact on the physical and biological properties of the soil. Regardless of the plant species used as CC, we can expect an increase in the number of soil microorganisms and an improvement in the activity of soil enzymes. This effect is particularly beneficial in the case of reduced tillage systems. Mixing CC biomass with the topsoil loosens compacted soils and, in the case of light, sandy soils, increasing the capacity of the sorption complex. The size and composition of CC biomass and weather conditions during the vegetation period and during the covering of the soil with plant biomass are of great importance for improving the chemical properties of the soil. A beneficial effect of CC, especially legumes, on the content of the mineral nitrogen in the topsoil is usually observed. Sometimes, an increase in the content of available forms of potassium (K) and/or phosphorus (P) is also achieved. The effect of CC on the content of soil organic carbon (C), total nitrogen (N), or soil pH is less common. CC used in reduced tillage systems can significantly improve the yield and quality of cereal grain, especially when legumes are used as CC in low-fertility soil conditions and at low fertilization levels. However, non-legumes can also play a very positive role in shaping soil properties and improving cereal yield. [ABSTRACT FROM AUTHOR]

Novel crop rotation is an important factor influencing the composition of soil microorganisms. However, the effect of introducing oilseed and cover crops (CCs) into monoculture durum rotations on soil microbial communities is not clear in the Northern Great Plains. The objective of this study was to evaluate the effects of 2-year durum (Triticum durum D.) rotations with Ethiopian mustard (Brassica carinata A.) or camelina (Camelina sativa L.) or a 10-species forage/CC mix planted to replace fallow rotations with wheat on soil microorganisms. This study was designed as a randomized complete block with three replications in a no-tillage system. The results showed that total bacterial proportion was significantly higher in durum following fallow and camelina compared to durum following CC and carinata. Total fungal proportion was significantly higher in durum following CC compared to durum following oilseed crops and fallow. The fungal-to-bacterial ratio was significantly higher in durum following CC compared to durum following camelina and fallow. The crop species, soil pH and highly variable rainfall influenced the microbial community dynamics. The abundance of specific microbial groups due to crop-related changes might play a key role in the yield of subsequent crops and soil biological health. This study provides valuable insights into the use of CC mix and oilseeds as an alternative crop for fallow in a wheat–fallow system under dryland farming conditions. Future work is required to elucidate the biological mechanisms and functions of the soil microbial communities in the preceding and subsequent crop relative to soil health and crop productivity. [ABSTRACT FROM AUTHOR]

Studying green manure in several returning methods to enhance soil fertility and crop benefits is a strong foundation for cropland nutrient management. However, how different types of green manures and their variable doses affect the efficacy of applied manures, either buried or mulched, remain overlooked. The objective of this study was to optimize green manure management to enhance soil fertility and maize biomass using five types of green manures (white mustard, forest rye, fiddleneck, sufflower, and pea) in two different doses (low, 5 g per pot, and high, 10 g per pot), which were either buried or mulched before and after maize sowing. Results revealed that total carbon content increased due to green manure treatments, representing a 10% increase over control, particularly through buried w. mustard (10% increase before maize cultivation) and mulched safflower and pea (12% and 11% increase after maize cultivation over control). Dry maize aboveground biomass yields also improved across all variants, with buried mustard yielding 18.4 g·plant−1 (compared to 8.6 g·plant−1 in the control), mulched mustard yielding 16.4 g·plant−1, and buried pea yielding 17.8 g·plant−1. Green mulching generally acidified the soil (pH 5.71 compared to 6.21 in the control), except for buried fiddleneck (pH 6.39 after maize cultivation) at a high dose of manures. Carbon-mineralizing enzyme activities (dehydrogenase and β-glucosidase) were significantly increased by green manures, with buried fiddleneck showing a 22.6% and 20.6% increase over the control, and mulched fiddleneck showing a 24.5% and 22.4% increase under high doses. The study suggests that partially decomposed and mineralized mulched biomass may induce a negative priming effect on carbon-mineralizing enzymes due to a decrease in the C/N ratio of the soil. It emphasizes that the nutrient content and stoichiometry of green manures, alongside soil characteristics such as the C/N ratio, are critical factors for sustainable soil management and carbon sequestration. These findings underscore the need for careful selection and management of green manures to optimize soil health and carbon-storage outcomes. [ABSTRACT FROM AUTHOR]

Investigating the impact of cover crops and manure on soil greenhouse gas (GHG) emissions is crucial for advancing our understanding of the climate-smart potential of organic management practices. This soil incubation experiment was conducted to investigate the combined effects of manure and cover crop residue decomposition on soil carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4) emissions under simulated tillage conditions. Undisturbed soil cores, collected from an organic cotton (Gossypium hirsutum L.) field experiment, were incubated for 90 days in a 2 × 4 factorial design for 2 consecutive years. Four combinations of cover crop and poultry litter (PL) residues were the primary treatment factor. The amount of residues added in the incubation study reflected the cover crop biomass produced under field conditions and the amount of PL applied in the field. Residue treatments included PL only at the full application rate (250 kg ha−1), PL with oat (Avena sativa L.), PL with turnip (Brassica rapa subsp. rapa), and half the rate of PL with Austrian winter pea (Pisum sativum) (AWP). The residues were either soil incorporated or surface applied to simulate disking and no-till field conditions. On average, 3.5% of applied carbon escaped as CO2 during the 90-day incubation period across treatments. Similarly, on average, 0.75% of applied nitrogen escaped as N2O. The proportion of nitrogen emitted as N2O under simulated no-till was 81.2% higher in 2020 (P < 0.05) compared to conventional tillage. In 2021, N2O emission was 35.8% higher (P < 0.1). When normalized over the amount of carbon added, total CO2 equivalent GHG emissions were the highest in the legume AWP treatment for both years. However, neither residue types nor simulated tillage affected net soil CH4 uptake (P > 0.1). While no-till practices may increase soil total carbon and nitrogen stocks during the cover crops and manure decomposition, the impact on GHG emissions depends on residue type and should be considered in estimating the climate-smart potential of organic management practices. [ABSTRACT FROM AUTHOR]

Conservation management practices often produced positive but limited desirable outcomes in US Southeast sandy soils, likely due to their intrinsically low clay contents that constrain the soil’s capacity to preserve organic carbon (C) and nutrients. In the field, we tested the effectiveness of a novel approach, that is, clay soil amendment, to improve sandy soils. In October 2017, clay-rich soils (25% clay) were spread at 25 metric tons ha−1 and tilled onto a sandy soil (1.9% clay) in the field, which was further mixed by light tillage at 0- to 15-cm depth, followed by planting winter cover crop mixtures (cereal rye, crimson clover, and winter pea). The crop rotation was cotton and corn with cover crop mixtures planted in the winter fallow season. Soils (0–15 cm) were collected in August 2021 and subjected to physiobiochemical analyses. Clay amendment increased soil clay content to 3.4%, which improved nitrogen (N) availability by 51% but inhibited the activities of C (β-Dcellubiosidase [CB]; β-xylosidase [BX]; N-acetyl-β-glucosaminidase [NAG]) and N (leucine aminopeptidase [LAP]) cycling enzymes, resulting in up to 78% reduction in microbial respiration. A follow-up kinetic study on BG and LAP enzymes suggested that clay addition can have different impacts on enzymes with diverse biological origins through distinct mechanisms. Clay addition can potentially improve sandy soils by stabilizing the organic inputs in soils. However, more research is required to understand its long-term impacts making this approach practical. [ABSTRACT FROM AUTHOR]

Management practices such as relay cropping, cover crops, and no-tillage may promote soil health in the North Central United States. However, soil health indicators in corn (Zea mays L.)–soybean [Glycine max (L.) Merr.] systems involving multiple management practices are not well documented. The objective of this study was to determine the sensitivity of soil health metrics and the Soil Management Assessment Framework (SMAF) to contrasting management systems with different tillage, crops, and fertilization in a North Central US Mollisol. Different management systems, including conservation tillage and nitrogen fertilization strategies, cover cropping, and camelina [Camelina sativa (L.) Crantz] relay intercropping, were compared to a conventional corn–soybean system. Different systems did not affect most soil health indicators compared to the conventional system. Aggregate stability was the only indicator to change due to management, where no-till with cover crops increased aggregate stability by 38% compared with camelina relay cropping. The SMAF scores for all the soil quality indices were unaffected by treatments but displayed high values of over 90%. Overall, crop yields were more closely related to weather conditions and management systems than to soil health indicators. Soybean yields were decreased (between 1 and 2 Mg ha−1 ) in the camelina relay cropping system, while corn yields were lower (up to 70%) in the treatment that received no N fertilization. Ultimately, these findings suggest that soil health indicators are resilient to change due to management in these highly productive Mollisols and may not be closely associated with crop yields. [ABSTRACT FROM AUTHOR]

Sustainable agricultural development not only addresses global food insecurity but may also alleviate poverty by enriching the lives of millions of smallholder farmers. Improving the sustainability and profitability of agriculture where smallholders are dominant creates profound impacts because small landholding farmers produce approximately 70–80% of the global food. The need for a thorough understanding of the factors affecting farmers' adoption of agricultural technologies and practices has been identified from extant literature as an important research gap. Responding to the research gap and need, this study examined the challenges that prevent farm households from adopting improved farming practices and/or technologies in Banteay Meanchey and Battambang provinces in Northwest Cambodia. A total of 524 rice producing farm household representatives were randomly selected from a household database maintained by the local government authorities. A mixed methods approach was used in the study including semi-structured interviews followed by in-depth interviews, field observations, and literature review. Farmers were found to be confronted with a range of challenges and concerns, including soil degradation, weeds, diseases, insect pests, high production costs, flooding, droughts, changing rainfall pattern, and unreliable rainfall distribution. The research findings demonstrate that improved crop production practices (e.g., adopting mechanised direct seeding methods of crop establishment, maintaining and improving soil health through crop residue retention, growing cover crops, etc.) and better resource use efficiency (e.g., reducing seeding rates to less than 100 kg/ha, being more strategic in the use of integrated nutrient, weed, and pest management strategies, etc.) can be a starting point for sustainable intensification of rice production. This transition towards intensifying paddy production sustainably may become even more effective through a clear understanding of local contexts, farm household characteristics, available resources, and the farm management practices and constraints. We observed that farmers and their associations have yet to be fully recognised as partners and actors in Cambodia. Instead, they tend to be viewed as beneficiaries and recipients of improved practices and technologies. We, therefore, propose that farmers and their associations be acknowledged and included in a process of co-creation of knowledge-practices. Such partnerships will enable the inclusion of factors (e.g., production costs, production risks, complexity and practicability of implementations, product market and prices, etc.) shown to influence farmers' adoption of innovative farming practices and technologies. The original contribution of this article is a real-world account of the constraints and limitations experienced by smallholder rice farmers in Cambodia, which are connected to future research and development priorities in the region. [ABSTRACT FROM AUTHOR]

The use of cover crops (CCs) based on tropical legumes, including Crotalaria ochroleuca, Crotalaria juncea, Crotalaria spectabilis, and Cajanus cajan, represents a pivotal aspect of agricultural rotations. These crops facilitate the incorporation of nitrogen through biological nitrogen fixation (BNF), thereby reducing the necessity for synthetic nitrogen fertilizers. Nevertheless, the capacity for the BNF of these species in Uruguay is relatively modest. To address this limitation, an approach is proposed that involves the immobilization of nitrogen in the soil using a highly energetic material, such as sucrose. The objective of this study was to examine the impact of incorporating sucrose into typical Uruguayan soil on aboveground dry matter production, nitrogen accumulation, and nitrogen fixation by legumes utilized as CCs. The experiments involved the planting of C. ochroleuca, C. juncea, C. spectabilis, and C. cajan in pots containing either soil alone or soil mixed with sucrose and the subsequent maintenance of these in a plant growth chamber for a period of 90 days. The addition of sucrose had a positive impact, with nearly double the aboveground dry matter production and nitrogen content observed. The percentage of nitrogen derived from the atmosphere (%Ndfa) increased significantly in all species, rising from an average of 83% to 96% in the sucrose-amended soil compared to the control. In the case of C. juncea, there was a notable threefold increase in aboveground dry matter and nitrogen accumulation across different treatments, accompanied by a 26% rise in %Ndfa and a fourfold increase in nitrogen fixation amounts. These findings indicate that C. juncea has the potential to significantly enhance performance and ecosystem services in typical Uruguayan soil. [ABSTRACT FROM AUTHOR]

In Iran, particularly in the Zagros forests, natural land uses are increasingly being converted into agriculture, which can negatively influence soil hydrological processes. To study this, three replicate micro-plots were installed on similar slopes in the forest (FO), rangeland (RA), and vineyard ‒ under the canopy (VUC) and in the inter-row space (VIR) ‒ to measure soil loss and surface runoff. Top- and sub-soil samples were randomly taken in three replicates from three sites for each land use/cover (LUC). Standard laboratory methods were utilized to measure the designated soil properties. According to the results, soil organic matter (SOM), aggregation indices, residual (ϴr) and saturated water content (ϴs), water content at field capacity (ϴFC), and saturated hydraulic conductivity (Ks) showed a significant decreasing trend as follows: FO > RA > VUC > VIR, whereas EC, pH, CaCO3, bulk density, and K-factor significantly showed an increasing opposite trend. LUC did not affect permanent wilting point (ϴPWP), available water content (AWC), and α and n van Genuchten's parameters. It was also found that RA and FO exhibited a higher repellency index than VUC and VIR. The forest had the lowest soil loss and runoff due to its higher porosity, SOM, aggregate stability, infiltration rate, water storage capacity, and surface cover. The highest soil loss and runoff were observed in VIR because of the vineyard's management operations and the bareness of soil between the vine rows. Conservation measures, such as no-tillage, mulching, or cover crops in the inter-row spaces, are recommended to mitigate these negative effects. [ABSTRACT FROM AUTHOR]

Since the introduction and widespread adoption of chemical herbicides, "weed management" has become almost synonymous with "herbicide management." Over-reliance on herbicides and herbicide-resistant crops has given rise to herbicide resistant weeds. Integrated weed management (IWM) identifies three strategies for weed management— biological-cultural, chemical-technological, mechanical-physical—and recommends combining all three to mitigate herbicide resistance. However, adoption of IWM has stalled, and research to understand the adoption of IWM practices has focused on single stakeholder groups, especially farmers. In contrast, decisions about weed management often occur within a social ecosystem where multiple stakeholder groups co-create knowledge and practices. To more holistically investigate perceptions and decision-making related to herbicide resistant weed management, we conducted 23 in-depth interviews in combination with Q methodology with farmers and public-/private-sector agricultural professionals in the state of Georgia (U.S.). Our investigation focused on the management of an increasingly herbicide resistant weed, Palmer amaranth, which enabled broader conversations about agricultural systems, farmer livelihoods, and sustainability. Factor and thematic analyses allowed us to identify and characterize two distinct typologies: one primarily valued agronomic efficiency and relied upon chemical-technological management practices, while the other valued diversifying weed management strategies as the pathway to agronomic and economic success. Typologies diverged substantially in attitudes toward the three weed management strategies, the role of technology, and systems management generally. These two viewpoints have implications for how we understand underlying stakeholder motivations and choices around weed management strategies, both of which are crucial in promoting and supporting farmer use of diverse, ecologically-sound, weed management strategies. [ABSTRACT FROM AUTHOR]

Cover cropping is practiced in conservation agriculture to preserve soil and water resources, alleviate soil compaction, sequester organic carbon, and control weeds. Meanwhile, cover cropping is rarely used in forestry, probably due to the lack of awareness of this management practice. In this short essay, we discuss the concept of utilizing cover crops to prepare degraded lands for afforestation or reforestation projects. The benefits of this practice are similar to those in agriculture. The risks of this practice are mostly related to plant-plant interactions, and particularly, to the potential competition for resources with the target trees. As such, this practice should be implemented cautiously, to prevent adverse impacts on the forest system. Also, attention should be paid to ensure the delivery of ecosystem services and functions by the target land. Further, the co-use of complementary practices may be considered to accelerate the success rate of cover cropping in degraded lands designated for afforestation and reforestation. Among these practices, application of soil additives, such as composts, manures, and biochars, may be useful in increasing soil concentrations of organic carbon and nutrients, thus improving soil quality and fertility. Additional complementary active practices may be the direct seeding or planting of nurse shrubs and trees, as well as the inoculation of soil surface with biocrust slurries, aimed to increase ecosystem complexity by forming a multi-story vegetation structure. Recommendations and guidelines for implementing cover crops in forestry should be site-specific and case-dependent, and consider both the desired benefits and potential risks. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) loss following manure application is an environmental concern and N loss for crop production. Manure injection typically reduces NH3 loss compared to surface application without incorporation but increases emissions of nitrous oxide (N2O), which is a potent greenhouse gas. Synchronizing manure in spring with cover crop (CC) growth may increase N recovery and reduce N2O emissions compared to applying manure later in the absence of growing crops. We compared the two following manure application methods: shallow-disk injection (IM) or surface banding without incorporation (BM) to annual ryegrass (Lolium multiflorum L.) and red clover (Trifolium pratense L.) CC at two times: early spring on growing CC (EARLY) and late spring on terminated CC (LATE). The randomized split-plot block experiment was conducted at Rock Springs, PA, during 2021–2022. After manure application, we measured NH3 for 72 h and N2O throughout the growing season. Aboveground CC biomass, N, and C:N ratio; pre-sidedress soil nitrate; corn (Zea mays L.) stalk nitrate; and silage yield were assessed. Averaged across application times, compared to BM, IM reduced cumulative NH3 loss, increased soil N, and resulted in 13% greater corn yield but increased yield-scaled N2O. Compared to BM LATE, BM EARLY reduced NH3 loss by 43%, increased CC N, reduced N2O emission by 50%, but decreased corn yield by 11%. When IM was EARLY compared to LATE, CC N increased 84%, cumulative N2O loss decreased 55%, and corn yield was similar. Injecting manure to growing CCs offers a strategy for reducing detrimental NH3 and N2O emissions and maintaining corn yield. [ABSTRACT FROM AUTHOR]

Environmental awareness about soil and water conservation in agroecosystems has shifted behaviors toward favoring conservation practices in agricultural management. Interest in conservation tillage and cover cropping has increased, but some regions encounter major challenges with adjusting management to accommodate these practices while optimizing crop production. In an Ultisol in the North Carolina Piedmont, a long-term corn (Zea mays) and soybean (Glycine max) rotation with tillage intensities ranging from no-till to moldboard plowing in a randomized complete block design was used to assess changes in physical soil properties after introducing wheat (Triticum aestivum) as a winter cover crop. Cover crop biomass was measured along with volumetric water content (VWC) and bulk density (BD) at 0–15 cm, water retention (WR), water-stable aggregation (WSA), and soil organic carbon (SOC) at 0–7.5 cm, and penetration resistance (PR) at 0–45 cm. No differences in VWC or WR could be solely attributed to cover cropping, but no-till with cover cropping had the highest macroporosity where there was no vehicle traffic. Vehicle traffic had a stronger effect on soil compaction (BD and PR) than cover cropping regardless of tillage. Conservation tillage increased WSA and SOC when compared to plow tillage, but three seasons of a wheat cover crop did not significantly change these properties, possibly because wheat produced low biomass each year (750–1900 kg ha−1). Wheat had minimal effect on physical soil properties in the short term, and potential for improvement with long-term optimal cover crop management in this region requires further assessment. [ABSTRACT FROM AUTHOR]

Repetitive use of heavy farm machinery in cultivated agriculture may cause soil compaction that can adversely affect soil‐health‐related properties. Cover crops (CC) are well‐documented to alleviate problems associated with compaction and improve overall soil health in time. The objective of this field study was to evaluate the cumulative effects of CC treatment (i.e., with ≥ 6 years cereal rye [Secale cereale L.] CC and ≥ 4 years with no cover crop [NCC]) and sample/measurement placement (i.e., in the bed [B] and in the wheel‐track [WT] and no‐wheel‐track [NWT] furrow) on near‐surface soil physical‐, chemical‐, and infiltration‐related properties in an alluvial soil under cotton (Gossypium hirsutum L.) production in the Lower Mississippi River Valley. Samples were collected and in‐situ measurements were conducted in late May 2019 within a single field in eastern Arkansas. Overall‐infiltration rate was two times greater (p ≤ 0.01) in B compared to WT and NWT placement, which did not differ. Soil bulk density in WT was 1.1 times greater than the other two placements, while soil organic matter was greater in CC‐WT (30.7 Mg ha−1) than in all other treatment‐placement combinations, except for CC‐NWT, which did not differ. Similarly, water‐stable‐aggregate concentration was 2.3 and 1.6 times greater in the CC‐NWT and CC‐WT combinations, respectively, which did not differ, compared to under NCC. Results demonstrated that CC benefits extended beyond the bed to positively affect soil properties in adjacent WT and NWT furrows. Continued small‐scale, long‐term management studies using CC will extend insight into site‐specific, soil‐health improvements. Core Ideas: Cover crop use in cotton production reduced compaction and improved soil health in eastern Arkansas.Soil bulk density was greater in wheel‐track than in the bed and no‐wheel‐track placements.Soil organic matter was greatest in cover crop‐wheel and no‐wheel track treatment‐placement combinations.Wheel‐ and no‐wheel‐track water‐stable aggregation was greater in cover than no‐cover treatments. [ABSTRACT FROM AUTHOR]

Integrated crop‐livestock systems (ICLS) bring diversity to agricultural systems, enhancing soil ecosystem services, food production, and environmental sustainability. Resource utilization efficiency practices under semiarid ecoregions include dual systems that grow wheat (Triticum aestivum L.) for both grain and grazing (G) and recently complementary to wheat dual systems, cover crops (CC) for feeding both the soil and cattle during the fallow period. The latter continues to generate interest and there is a paucity of information on associated biochemical cycles. The objective was to evaluate the impact of CC and grazing thereof on soil microbiota structure, diversity, proliferation, and nutrient cycling. Introducing CC to no‐till (NT [NTC]) and grazing CC (NTCG [ICLS]), increased total PLFA biomass (TPB) for ungrazed CC (NTC) by 12%, and grazed CC (NTCG [ICLS]) by 20%; total bacteria biomass (TBB) by 10% for NTC and 24% for NTCG; total fungal biomass (TFB) by 9% for NTC and 21% for NTCG. The CC significantly increased Gram (−) bacteria biomass by 17% and 34% for NTC and NTCG, respectively; the CC significantly increased Gram (+) bacteria biomass by 6% and 12% for NTC and NTCG, respectively; and the CC significantly increased arbuscular mycorrhizal fungi by 55% and 89% for NTC and NTCG respectively, compared to NT fallow practice. Significant correlations were observed for NO3−–N, NH4+–N, water‐extractable organic nitrogen, total nitrogen, and water‐extractable organic carbon with TPB, TBB, and TFB using Haney soil health methods. Based on the measured parameters, the soil health status decreased in the order NTCG > NTC > NT > CT, where NT is the no‐till, C is the cover crop, G is the grazing, and CT is the conventional‐till. Grazing CC enhanced soil bacterial biomass over CC in solitude. Core Ideas: All cover crops (CC) increased actinomycetes, arbuscular mycorrhizal fungi, and Gram (−) and (+) and undifferentiated biomasses.Grazed CC further increased actinomycetes, Gram (−), and undifferentiated biomasses compared to ungrazed CC.High correlations for phospholipid‐linked fatty acid biomass with NO3−–N, NH4+–N, water extractable organic nitrogen, total nitrogen, and water extractable organic carbon were observed. [ABSTRACT FROM AUTHOR]

Cover crops have emerged as a crucial tool in promoting sustainable agricultural practices, particularly in improving soil quality and soil–plant health. This study investigates the impact of single cover crop plants each with varying fungal and/or bacterial symbiosis capacities in a pot experiment. The growth of non-symbiont Ethiopian mustard (Brassica carinata), the associative bacterium symbiont black oat (Avena strigosa) and the double (fungus–bacterium) endosymbiont broad bean (Vicia faba) was studied on three distinct soil types, namely a less-fertile sandy soil (Arenosol), an average value of loam soil (Luvisol) and a more productive chernozem soil (Chernozem). Beside the biomass production, nitrogen content and frequency of AM fungi symbiosis (MYCO%) of cover crops, the main soil health characteristics of electrical conductivity (EC), labile carbon (POXC) and fluorescein diacetate enzyme activity (FDA) were assessed and evaluated by detailed statistical analysis. Among the used soil types, the greatest biomass production was found on Chernozem soil with the relatively highest soil organic matter (2.81%) content and productivity. Double symbiotic activity, assessed by soil nitrogen content and mycorrhiza frequency (MYCO%), were significantly improved on the lowest-quality Arenosols (SOM 1.16%). In that slightly humous sandy soil, MYCO% was enhanced by 45%, indicating that symbiosis was crucial for plant growth in the less-fertile soil investigated. After the initial cover crop phase, the accumulated biomass was incorporated into the Luvisol (SOM 1.64%) soil, followed by the cultivation of corn (Zea mays, DK 3972) as the main crop. The results indicate that incorporating cover crop residues enhanced labile carbon (POXC) by 20% and significantly increased the FDA microbial activity in the soil, which positively correlated with the nutrient availability and growth of the maize crop. This study emphasizes the importance of selecting suitable cover crops based on their symbiotic characteristics to improve soil quality and enhance soil–plant health in sustainable agricultural systems. [ABSTRACT FROM AUTHOR]

Cotton, with a cultivated area of 31.92 × 106 ha−1 across 80 countries and an estimated annual turnover of USD 5.68 billion, is the world's leading natural textile fiber. However, many cotton-producing countries have neglected to improve production practices, adversely affecting the environment and society. A systematic review of the sustainable cotton cultivation literature was performed for the first time to identify and suggest context-specific agricultural strategies that can be applied within different agroecosystems. The key aspects include (1) inoculation with arbuscular mycorrhizal species such as Gigaspora margarita, Funneliformis mosseae, and Acaulospora scrobiculata to enhance root exploration, biomass, and nutrient uptake; (2) using grass, legume, and brassica cover crops as a valid alternative to monoculture and fallow crop rotations to reduce resource depletion and increase the sustainability of cotton production; (3) adopting drip and mulched drip irrigation systems over traditional furrow and sprinkler systems for water conservation; (4) exploring the feasibility of prematurely terminating irrigation in humid subtropical and Mediterranean climates as an alternative to chemical defoliation without affecting cotton yield. This paper, which describes various farming practices adopted in different climates, provides farmers a guide for eco-friendly cotton agronomic management without sacrificing productivity. [ABSTRACT FROM AUTHOR]

Weeds compete for environmental resources, leading to reduced soybean yield. In this context, integrated weed management strategies related to cultural control with the use of cover crops are necessary. Our aim was to evaluate weed occurrence in soybean systems with different cover crops. Field studies were conducted at Júlio de Castilhos, Santa Maria, Capão do Leão, Barra do Ribeiro, and Santo Ângelo, Rio Grande do Sul, Brazil. A randomized complete block design with four replications was used. Treatments consisted of black oats (Avena strigosa Schreb.), white oats (Avena sativa L.), rye (Secale cereale L.), hairy vetch (Vicia sativa L.), forage turnip (Raphanus sativus L.), and white clover (Trifolium repens L.) in pure stands or in mixtures. The analyzed variables were relative frequency, density, abundance, and importance value index, similarity index of weeds, dry shoot mass of cover crop, and soybean yield. Cover crops containing white or black oats reduced the relative importance value index of weeds, such as Lollium multiforum, Conyza spp., and Bidens pilosa. Forage turnip, hairy vetch, and white clover showed distinct responses. Black oats and forage turnip did not differ from cover crop mixtures in terms of dry shoot mass and grain yield, being superior to fallow, white clover, and hairy vetch. [ABSTRACT FROM AUTHOR]

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Pepper cultivation in Bangka Island primarily takes place on sandy land. Legume cover crops, such as Centrosema pubescens, which has been widely used as a ground cover, are anticipated to improve land quality by maintaining soil temperature and humidity, increasing soil organic carbon content, increasing soil porosity, and improving soil fertility. This research aims to analyze the agroecosystem of pepper plants, by comparing the use of the cover plant C. pubescens as a soil treatment and the absence of using these cover plants as a control. The research was conducted in farmers’ pepper gardens in Perlang Village, Central Bangka Regency, Bangka Belitung Province. The research employed a randomized block design, with C. pubescens and natural vegetation as treatments, each replicated 3 times. The variables measured were soil temperature and humidity; abundance of microorganisms; weed density, frequency, and dominance; chlorophyll a, chlorophyll b, and anthocyanin content of pepper leaves; photosynthesis rate; transpiration rate; stomatal conductance; soil chemical and physical properties. The results showed that C. pubescens as ground cover could reduce the dominance of the Bidens pilosa weed (relative dominance of 36.16%) but led to an increase in the dominance of Chromolaena odorata (relative dominance of 38.7%). C. pubescens ground cover could also maintain stable soil temperature and moisture, and increase P, K, Ca, and Mg soil content by 100%, 100%, 43.6%, and 48.3%, respectively. Furthermore, pepper plants grown with C. pubescens exhibited 25%, 23.7%, and 16% higher chlorophyll a, total chlorophyll, and carotenoid content, respectively, compared to those grown without the cover crop.

Conservation practices are encouraged to improve soil health and sustain agronomic crop production. Mehlich-3 is often used as a multi-nutrient extractant to determine soil fertility status. A study investigated the impacts of the conservation practices of gypsum, cover crops, and crop rotation on 28 Mehlich-3 extractable elements, of which 11 were considered plant nutrients, from soil at three midwestern US locations. Soil was collected from 0 to 15 and 15–30 cm depths 5 years after implementing the conservation practices. Treatments consisted of (1) with and without cereal rye (Secale cereale L.) winter cover, (2) continuous soybean [Glycine max (L.) Merr.] vs. soybean-corn (Zea mays L.) rotation, and (3) annual gypsum application (0, 1.1, and 2.2 Mg ha−1). Differences were observed by site, depth, and conservation practice depending on the element evaluated. Minimal interactive effects were observed among treatments. The most consistent effect was observed for crop rotation across sites. Gypsum only affected the site with the greatest clay content, where more Ca and S were retained, and Mg and Mn displaced. Cover crop only affected elements at this high clay site, where different elements were positively or negatively affected. Results suggest that not one practice fits all, and optimum conservation practices must be tailored for the site.

Cotton cultivation in the United States is relevant globally, with the nation ranking among the top producers and exporters. This study examines conservation practice adoption trends and technological advancements in U.S. cotton production, focusing on sustainability and productivity. Efforts to improve cotton farming practices have reduced its environmental impacts, including decreased soil loss, water usage, and greenhouse gas emissions. Precision agriculture technologies have been instrumental in enhancing efficiency and reducing input costs, albeit with varying degrees of success. To gain deeper insights into cotton grower challenges and needs, a Natural Resource Survey was conducted in 2023 with 753 respondents. As a follow-up to the 2008 and 2015 surveys, the insights from this survey provide valuable data on grower practices and priorities, highlighting the increasing influence of climate change on cotton production. The findings underscore the importance of conservation agriculture and ongoing research to address grower concerns while improving production efficiency. Particularly noteworthy are the outcomes indicating an increase in cover crop adoption and a decrease in tillage practices, reflecting the industry’s commitment to sustainability. This study contributes to understanding the dynamics shaping the U.S. cotton industry and offers insights into the challenges and opportunities for continual improvement in U.S. cotton cultivation.

The research presented in the article was focused on determining the C-factor for hops for conventional cultivation (CT) and soil conservation technique, which is based on the presence of cover crops (CC) in the inter-rows. The values of the soil loss ratio, which are the basis for the calculation of the C-factor, are also presented. The research activities were carried out between 2016 and 2023 and a field rainfall simulator was used for the measurements. Rainfall simulations were conducted at three developmental stages of CC. The results show a high C-factor value for CT (0.73), which indicates insufficient erosion control efficiency. In contrast, a C-factor of 0.16 was determined for the cover crop technique. This means that cover crops in the inter-rows of hop gardens can effectively reduce the risk of water erosion. The values reported in the article can be used as input parameters in various erosion models and equations to refine the subsequent calculation.

Abstract Background Achieving a net zero greenhouse gas United States (US) economy is likely to require both deep sectoral mitigation and additional carbon dioxide removals to offset hard-to-abate emissions. Enhancing the terrestrial carbon sink, through practices such as the adoption of no-till and cover cropping agricultural management, could provide a portion of these required offsets. Changing domestic agricultural practices to optimize carbon content, however, might reduce or shift US agricultural commodity outputs and exports, with potential implications on respective global markets and land use patterns. Here, we use an integrated energy-economy-land-climate model to comprehensively assess the global land, trade, and emissions impacts of an adoption of domestic no-till farming and cover cropping practices based on carbon pricing. Results We find that the adoption of these practices varies depending on which aspects of terrestrial carbon are valued. Valuation of all terrestrial carbon resulted in afforestation at the expense of domestic agricultural production. In contrast, a policy valuing soil carbon in agricultural systems specifically indicates strong adoption of no-till and cover cropping for key crops. Conclusions We conclude that under targeted terrestrial carbon incentives, adoption of no-till and cover cropping practices in the US could increase the terrestrial carbon sink with limited effects on crop availability for food and fodder markets. Future work should consider integrated assessment modeling of non-CO2 greenhouse gas impacts, above ground carbon storage changes, and capital and operating cost considerations.

Most soybean producers in the Cerrado biome use the direct seeding system, making it essential to cultivate cash or cover crops in the off-season, to promote soil protection, as well as increase organic matter, which is directly related to improvements in the chemical and physical characteristics of these soils. In this sense, this work was conducted in Jataí, state of Goias, Brazil, to evaluate the physical-chemical attributes of the soil and the performance of soybeans cultivated in different crop succession systems cultivated for 6 years in the region of Jataí, GO. The experimental design was randomized blocks with four plots and four replications; the crops that followed soybeans were arranged as follows: T1—corn (Zea mays); T2—pearl millet (Pennisetum glaucum); T3—Urochloa ruziziensis; and T4—corn + Urochloa ruziziensis. Soybean yield components and grain yield were evaluated in two harvests (2020/2021 and 2021/2022). Deformed and undisturbed soil samples were collected in 2022 to assess soil fertility and for physical analysis. The data were subjected to analysis of variance (F test) and the means were compared using the Tukey test at 5% probability. The soybean–millet succession system stood out for the chemical and physical attributes of the soil: calcium, magnesium, base saturation, hydrogen + aluminum, and total porosity. The crop succession system did not affect yield for the two years analyzed, but the accumulated grain yields were higher in the crop succession soybean/corn intercropped. The results highlight the importance of using cover crops in improving the physical and chemical qualities of the soil in the long term. However, in the Cerrado, there is a predominance of the soybean/corn succession system motivated by financial issues to the detriment of the qualitative aspects of the soil, in which the introduction of Urochloa ruziziensis in intercropping with corn would improve the chemical attributes of the soil and have a long-term impact on the accumulated grain production. [ABSTRACT FROM AUTHOR]

A survey of New Brunswick (NB) and Prince Edward Island (PEI) potato fields in crop rotation phase prior to potato production was conducted in fall (October and November) between 2017 and 2021. A total of 113 and 126 fields for NB and PEI, respectively, were surveyed with 20 to 35 fields each year tested in each province. Root lesion nematodes (RLN, Pratylenchus spp.) were detected in 99 and 98% of the fields for NB and PEI, respectively, and two root lesion nematode species, P. crenatus and P. penetrans, were identified in both provinces from 2017 to 2021. Based on 2019 and 2020 results, all surveyed fields in NB and PEI were detected with P. crenatus, while only 29 and 43% of the fields in NB and PEI were detected with P. penetrans, respectively. P. crenatus accounted for 96 and 89% of the populations for NB and PEI, respectively, while P. penetrans accounted for 4 and 11% in commercial fields, respectively. In a single in-depth sampled experimental field with a history of severe potato early dying complex in 2018 in NB, P. crenatus accounted for 88% and P. penetrans was 12%. Verticillium dahliae was detected in 94 and 92% of potato fields in NB and PEI, respectively. All isolates obtained from potato cv. "Russet Burbank" in a baiting trial were V. dahliae, belonging to two lineages. V. albo-atrum was detected in a few fields at very low level, except two fields in NB where V. albo-atrum was predominating over V. dahliae. Rotation crops did not affect V. dahliae population densities for NB and PEI, and did not affect RLN population in NB, but significantly affected RLN in PEI. Fall green cover crop did not affect the populations of RLN and V. dahliae in PEI. The present study revealed that the potato pathogenic root lesion nematode P. penetrans was present in less than 50% of surveyed fields and accounted for around 10% of root lesion nematode population in NB and PEI, and V. dahliae was the dominant species and was present in greater than 90% of surveyed fields in both provinces. [ABSTRACT FROM AUTHOR]