Search Results (223)

Farmers worldwide use agrochemicals and biological inputs to fertilize fields, manage pests and diseases, and promote plant growth. However, there is still limited field-based evidence on the extent to which biological inputs function as substitutes, incremental complements, or alternatives to agrochemicals in key farming practices. This study presents preliminary results on the use of synthetic and biological inputs for the most common practices employed by large soybean farmers in central Brazil. We combined literature review, regulatory data on registered biological products, and in-person interviews with farmers and market experts. Our results show that, in most practices, biological products are adopted alongside the continued use of synthetic inputs, in some cases reducing the frequency or dosage of chemical applications. Inoculants based on nitrogen-fixing bacteria already substitute mineral nitrogen fertilization in soybean, while biosolubilizers and plant activators are used incrementally to enhance the efficiency of chemical fertilizers. Bioinsecticides and biofungicides are predominantly employed as alternatives within spray programs, especially in preventive or early interventions, thereby reducing the number of conventional pesticide sprays. Bionematicides emerge as the main biological tools used as substitutes for synthetic nematicides in preventive treatments, whereas biological herbicides are not yet available on the market. Field evidence presented in this study showed that farmers adopt biological products in diverse ways, including as substitutes, incremental, or alternatives to chemical products, depending on the technologies available. These findings provide a more nuanced understanding than the common views that, on one hand, biological inputs simply complement rather than substitute chemical products, and on the other, that biological solutions can fully substitute synthetic products. As environmental and economic implications, we conclude that biological inputs can underpin trajectories towards more regenerative management in large-scale soybean systems, even when synthetic inputs remain part of the production matrix. Full article

Oxidative stress has emerged as a key factor regulating female fertility, reproductive aging, and the development of various gynecologic and pregnancy-associated diseases. While physiological concentrations of reactive oxygen species play a fundamental role in many aspects of normal reproduction such as folliculogenesis, oocyte maturation, implantation, and placental development, abnormal or chronic oxidative stress impairs redox homeostasis and promotes mitochondrial dysfunction, inflammation, DNA damage, and cellular senescence. Recent research interest has shifted toward next-generation dietary antioxidants, including bioactive polyphenols, carotenoids, micronutrients, and nutraceutical combinations with improved bioavailability and molecular targets. These compounds go beyond classical free-radical scavenging activity and modulate a network of redox-sensitive signaling pathways involved in autophagy, apoptosis, endocrine regulation, and immunological balance. In this review, we integrate current mechanistic advances into a cohesive framework that illustrates the regulation of key cellular processes affecting female reproductive physiology by next-generation dietary antioxidants. We also critically evaluate experimental, translational, and clinical data supporting their role in promoting reproductive outcomes, including oocyte quality, ovarian reserve, pregnancy success, and mitigation of age-related reproductive decline. We highlight their potential in the therapeutic intervention of oxidative stress-related conditions such as infertility, polycystic ovary syndrome, endometriosis, early ovarian insufficiency, and menopause-associated disorders. Finally, we discuss the current challenges associated with dosage optimization, bioavailability, long-term safety, and interindividual variability. We conclude by highlighting next-generation dietary antioxidants as a promising, widely available, and non-invasive approach to improve women’s reproductive health and promote fertility throughout their lifespan. Full article

Calcium cyanamide (CaCN₂), commercially known as Perlka^®, is re-emerging as a multifunctional nitrogen (N) fertilizer with significant agronomic and environmental advantages. Composed of 19.8% nitrogen and 50% calcium oxide (CaO), CaCN₂ not only supplies slow-release nitrogen but also acts as a liming agent, improving soil pH and structure. Its transformation pathway: cyanamide → urea → ammonium → nitrate—ensures a gradual nitrogen release that aligns with crop demand, enhances nitrogen use efficiency, and minimizes nitrate leaching and nitrous oxide emissions. Additionally, the presence of dicyandiamide, a known nitrification inhibitor, further stabilizes nitrogen in the soil. Field studies across diverse cropping systems, including curly endive and short-day onions, have demonstrated that CaCN₂ improves yield, crop quality, and soil health. In onions, preplant application of 80 kg ha⁻¹ N from CaCN₂ increased bulb yield by up to 18%, enhanced phytochemical content (e.g., phenolics and flavonoids), and reduced nitrate leaching by over 40% compared to urea and limestone ammonium nitrate (LAN). In curly endive, CaCN₂ significantly improved ascorbic acid, total soluble solids, and phenolic content, particularly in fall-grown crops, while reducing nitrate accumulation and improving physiological and recovery efficiency of applied nitrogen. Beyond its role as a nutrient supplier, CaCN₂ exhibits biocidal properties that suppress soil-borne pathogens such as Sclerotinia and Plasmodiophora brassicae, reduce weed pressure, and stimulate beneficial microbial activity. Its high calcium content also addresses physiological disorders linked to calcium deficiency, such as tip-burn and blossom-end rot. However, proper application timing and dosage are critical to avoid phytotoxicity, especially in sensitive crops. This review synthesizes current knowledge on CaCN₂’s chemical behavior, agronomic performance, and environmental implications, and identifies research gaps to guide its optimized use in climate-smart and resource-efficient agriculture. Full article

Phosphogypsum, a by-product of phosphate fertilizer production, has shown promising potential as a shrinkage-reducing additive in ordinary Portland cement-based mortar. The incorporation of low PG dosages (≤6%) enhances early hydration, slightly increases the hydration peak temperature, and promotes the formation of additional ettringite and bound-water-rich hydrates, contributing to improved early performance. PG also substantially reduces drying shrinkage—from 0.0397 mm/m (reference) to −0.1600 mm/m at 15% PG—through ettringite-induced expansion and pore refinement, demonstrating its effectiveness as a shrinkage-reducing agent. Thermal analysis (XRD/TG–DTA) confirms that PG modifies hydration chemistry by increasing low-temperature dehydration while reducing portlandite and carbonate phase formation due to clinker dilution. As a result, Ca(OH)₂ content decreases from 11.89 wt% for the reference mix to 8.55 wt% at 15% PG. However, higher PG levels (>9%) negatively affect strength: at 15% PG, flexural and compressive strength decrease by 38% and 47%, respectively, due to clinker dilution, excess ettringite, and unreacted gypsum. All compositions maintained durability levels corresponding to roughly 300–450 freeze–thaw cycles. Overall, PG effectively reduces shrinkage and alters hydration behavior while offering environmental benefits through industrial waste valorization. Nevertheless, high replacement levels compromise mechanical performance, underscoring the importance of optimizing PG dosage to balance shrinkage control, strength, and sustainability. Full article

This study is Part II of a five-year (2018–2022) field trial in western Portugal evaluating the effects of three microbial biofertilizers—Mycoshell^® (Glomus spp. + humic/fulvic acids), Kiplant iNmass^® (Azospirillum brasilense, Bacillus megaterium, Saccharomyces cerevisiae), and Kiplant All-Grip^® (Bacillus megaterium, Pseudomonas spp.)—applied at different dosages alongside two mineral fertilizer regimes, T100 (full dose) and T70 (70% of T100, alone or combined with biofertilizers), on the physiological performance of ‘Gala Redlum’ apple trees. Part I had shown that Myc4 (Mycoshell^®, 4 tablets/tree), iNM6, and iNM12 (Kiplant iNmass^®, 6 and L ha⁻¹, respectively) consistently enhanced fruit growth, yield, and selected quality traits. While Part I showed clear agronomic gains, Part II demonstrates that these improvements occurred without significant alterations in seasonal photosynthetic performance, canopy reflectance, or chlorophyll fluorescence parameters over five years, highlighting the contrast between observed yield improvements and physiological stability. Seasonal monitoring of physiological traits—including specific leaf area (SLA), chlorophyll content index (CCI), gas exchange (A_n, g_s, E, C_i), spectral indices (NDVI, OSAVI, SIPI, GM2), and chlorophyll fluorescence (OJIP). It is clear that physiological values remained largely stable across biofertilizer treatments and years. Importantly, this stability was maintained even under a 30% reduction in mineral fertilizer (T70), indicating that specific microbial biofertilizers can sustain physiological resilience under reduced nutrient inputs, thereby providing a physiological basis for the yield-enhancing effects observed and supporting their integration into fertilizer reduction strategies in Mediterranean orchards. Full article

Alfalfa cultivation is an effective way to achieve soil improvement while utilizing saline soils. Irrigation and drainage, as physical measures to leach salts, can effectively reduce the soil salt content, while application of organic fertilizer fermented with an effective microorganism (EM) may further enhance the improvement effect of saline–alkaline soil by improving soil fertility and microbial community structure. However, there is still a lack of systematic assessment on the effects of applying these three measures on the saline soil–plant system. In this study, we used alfalfa as the plant material and set three water depths of 8 mm (IR1), 16 mm (IR2), and 24 mm (IR3) under the condition of irrigating every 10 days with remote-controlled timed and quantitative irrigation, which is the most acceptable to farmers in the era of smart agriculture. EM organic fertilizer dosage was designed as 0 kg/ha (CK), 1500 kg/ha (OF1), 3000 kg/ha (OF2), 4500 kg/ha (OF3), and 6000 kg/ha (OF4). The multiple-crop alfalfa yield, quality (crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF)), and soil electrical conductivity (EC) were observed. The results showed that after the application of EM organic fertilizer, the soil’s EC value of fertilized treatments was higher than that of CK, but this difference became smaller with the prolongation of alfalfa’s growing period, implying that EM organic fertilizer could absorb more soil salts by promoting alfalfa’s growth; the water depth was obviously negatively correlated with the soil’s EC value, demonstrating that the increase in the water depth had a stronger ability to reduce the soil salts. By the end of the experiment, the soil’s EC values were reduced by 21.4–43.7% for the treatments. The alfalfa yield was significantly increased by EM organic fertilizer application, and the three alfalfa yields were increased by 63.3–69.1%, 65.4–83.6%, and 52.6–56.2%, respectively, when fertilizer application was elevated from CK to OF4. The highest alfalfa yields were all found at IR2OF4, reaching 1164.7, 2637.3 and 2519.7 t/ha, corresponding to the first, second, and third alfalfa crops, respectively. The analysis of alfalfa quality indexes revealed that higher CP values were found in the IR2 treatments, and increasing fertilizer application from OF1–OF4 resulted in an increase in CP values by 2.4–9.1%, 1.5–7.4%, and 0.8–6.7% for the three alfalfa crops. Relatively low NDF and ADF values were observed for alfalfa under IR2 conditions; however, the application of EM organic fertilizer reduced the NDF and ADF values within a certain range. According to the results of the entropy weight evaluation model, IR3OF4, IR3OF2, and IR3OF3 were the top three treatments with the best overall benefits, respectively, with relative closeness values of 0.71, 0.70, and 0.68, in that order, which suggests that the appropriate water depth is 24 mm, while the appropriate EM organic fertilizer dosage is in the range of 3000–6000 kg/ha. There was a pattern observed in our study, in which the treatments with better overall benefits were better distributed at high water depths, which emphasizes the critical role of the irrigation volume in ameliorating saline soils. The conclusions of the study are intended to provide a practical basis for the comprehensive utilization and sustainable development of saline soils. Full article

Agricultural residues, such as vineyard prunings, are abundant yet underutilized resources with potential for conversion into value-added products. In this study, vineyard prunings were investigated for the first time as feedstock for nutrient-enriched biochars intended for use as enhanced efficiency fertilizers (EEFs). Four biochars were produced using distinct physical (industrial-scale pyrolysis, CO₂-assisted pyrolysis) and chemical (MgCl₂, AlCl₃ pretreatment) procedures. Their adsorption capacities for nitrogen (N), phosphorus (P), and potassium (K) were evaluated across a wide pH range (2–13). Optimization studies, including dosage, kinetics, and isotherms, revealed maximum Langmuir adsorption capacities of 10.4 mg N g⁻¹ and 12.7 mg P g⁻¹, which were comparable to or higher than other low-cost agricultural biochars, confirming the competitive performance of vineyard pruning-derived biochars. Beyond adsorption efficiency, these biochars provide additional benefits by valorizing a widely available viticulture residue, reducing open-field disposal and burning, and generating low-cost fertilizers that may reduce nutrient leaching and improve soil health. This work introduces a novel circular pathway linking vineyard waste management to sustainable nutrient delivery, integrating agricultural byproduct utilization with environmental remediation strategies. Full article

Suspension fertilizers offer high concentration, excellent fluidity, an eco-friendly production process, and ease of precise and even application, making them ideal for modern fertigation systems. However, stability remains a significant challenge. This study aims to develop an organic value-added suspension fertilizer (VSuF) based on the filtrate of acid–base-treated soybean residue, which can ensure stability during transportation and storage while promoting efficient nutrient utilization in agriculture. The stabilizers were optimized by comparing the effects of various types and dosages on particle size, zeta potential, viscosity, and thixotropy of the suspension fertilizer. Meanwhile, the stability and agricultural effects of the fertilizer were evaluated. Results showed that with 0.40% sodium lignosulfonate, 0.40% xanthan gum, and 0.20% organic silicon defoamer, VSuF remained stable during centrifugation (2000 r·min⁻¹, 30 min) and storage at 0 °C and 50 °C for 14 days. Additionally, agricultural evaluation indicated that VSuF significantly increased the dry weight and phosphorus uptake of crop shoots by 17.40% and 21.00%, respectively, relative to the solid fertilizer without the value-added compound. Meanwhile, VSuF enhanced the fresh weight, length, and surface area of crop roots by 83.10%, 74.47%, and 69.34%, respectively, along with shoots’ phosphorus uptake by 19.80%, compared to the glucose value-added solid fertilizers. Full article

Sugar beet (Beta vulgaris L.) is an important economic crop and a primary source of sugar in northern China, characterized by strong stress tolerance and high nutritional value. Microbial inoculants can promote crop growth by regulating soil enzyme activities, enriching dominant beneficial bacterial genera in rhizosphere soil, and improving the availability of soil nutrients. This study aimed to investigate the role of microbial inoculants in sugar beet production and their potential to replace chemical fertilizers and put forward the scientific hypothesis that microbial inoculants can increase soil nutrients and improve the soil microenvironment. A two-year field experiment was conducted: in 2022, treatments with different application rates of Bacillus subtilis and Trichoderma spp. inoculants were set up to screen the optimal inoculant and its dosage (M1); in 2023, based on this optimal inoculant (M1), treatments with reduced chemical fertilizer input were established to explore the mechanisms underlying the maintenance of sugar beet yield and quality. The results showed that the M1N2 (75 kg/ha fertilizer and 20% less nitrogen fertilizer) treatment significantly increased nitrogen, phosphorus, and potassium agronomic use efficiencies by 91.48%, 51.94%, and 53.50%, respectively, compared with the control (CK). Soil urease, catalase, and sucrase activities were significantly enhanced by 14.57%, 66.84%, and 222.46%, respectively. The treatment also significantly increased the relative abundance of beneficial bacterial genera such as JG30-KF-CM45 and KD4-96, while sugar beet yield was significantly increased by 5.53% relative to the CK. This study provides a theoretical basis for the application of microbial inoculants and the reduction in chemical fertilizers in sugar beet production. Full article

This paper focuses on the resource utilization of phosphogypsum, a major industrial by-product from phosphate fertilizer production, in highway engineering materials, exploring its performance optimization and collaborative modification mechanisms. Phosphogypsum, primarily composed of CaSO₄·2H₂O, faces challenges such as acidity (pH ≈ 3.56), poor water resistance, and strength limitations, which hinder its engineering application. This study investigates pretreatment methods (e.g., lime neutralization, physical grinding) and the synergistic effects of additives like metakaolin, steel slag, slag powder, and stone powder. The results show that adjusting phosphogypsum’s pH to 10 via lime neutralization significantly improves its mechanical properties, with its 28-day compressive strength increasing by 21%. The optimal dosage of cement as an alkaline activator is 4%, while steel slag performs best at 10%. Metakaolin (11% dosage) enhances the 28-day strength of 30% phosphogypsum-containing systems by 89–114% through pozzolanic reactions, forming a high-strength aluminosilicate network, enabling the preparation of C35 concrete with a 28-day strength of 44.5 MPa. Additionally, stone powder exhibits the most effective strength improvement, with the 56-day strength increasing by 12.5 MPa compared with the reference group. Economically, utilizing 30% phosphogypsum and 11% metakaolin reduces C35 concrete costs by 15–20%. This research provides theoretical and technical support for the large-scale application of phosphogypsum in highway engineering, addressing environmental and economic challenges. Full article

The limited availability of phosphorus (P) in soil poses a critical constraint on agricultural productivity, and sustainable P fertilization practices are of great importance for crop production. In this study, we developed a novel dual-function granular material (RMG) derived from red mud, a waste residue from the aluminum industry. This material is capable of adsorbing P in P-rich soils and releasing P in P-deficient soils, thereby enabling the sustainable use of red mud and P fertilizer. The influences of RMG on the migration and transformation of P in soil were investigated. Application of RMG significantly increased the critical threshold for P leaching, thereby effectively mitigating P loss. In the initial stage of leaching, P in the leachate was present predominantly as particulate phosphorus, whereas molybdate-reactive P became the dominant form in later stages. With increasing RMG dosage, the pH of the leachate rose while the total phosphorus concentration declined, indicating that alkaline components in RMG promoted the adsorption and precipitation of phosphates in soil. The release behavior of P from P-enriched RMG was also examined. The results showed that the total soil P content increased progressively with higher RMG dosage and longer cultivation duration. Elevated temperature and soil moisture content were found to enhance the release and migration of P from RMG into the soil. SEM-EDS analyses revealed that released components (e.g., Ca²⁺ and Fe³⁺) from RMG formed relatively stable complexes with free phosphates. Moreover, adsorption of P onto the RMG surface further facilitated its migration and transformation within the soil. The research findings provide valuable insights for the simultaneous pollution remediation and resource utilization of red mud and phosphorus. Full article

The incorporation of cattle slurry in soil in short-rotation-cycle poplar cultivations can be a win–win strategy, insofar as a main feedstock derived from local intensive dairy cattle breeding can be used as a natural fertilizer and in bioenergy produced in the same region. The circularity of this process can contribute to boosting local socio-economic value. In this context, this work involved the installation of a poplar SRC plantation with a density of 5330 trees ha⁻¹ in a 4000 m² moderately fertile flat site, which was formerly used as a vineyard. Mechanical dosages of slurry of 0, 26.6, 53.2, and 106.5 Mg ha⁻¹, designated as treatments T0, T1, T2, and T3, were applied three times per year during 2019, 2020, and 2021. The variables quantified were related to plant growth, biomass productivity and mass balances of K, P, Cu, Zn, Mg, and N, and organic matter in the whole soil, plant, and slurry system during the first rotation cycle. For treatments T0 and T1, all these seven chemical components showed positive balances in the system, with cumulative demand by soil and biomass being higher than cumulative supply by slurry. Negative balances occurred for P with T2 and T3 and for Zn with T3, so that an overall condition of nutrient saturation of the whole system was not achieved. A no-slurry application, or at most a moderate application equivalent to T1, in the second rotation cycle should therefore be prescribed to allow a nutrient equilibrium status to be achieved through internal seasonal recycling mechanisms. The biomass average productivities ranged from 6.1 to 11.8 Mg ha⁻¹ y⁻¹, peaking under treatment T2, and are within the typical values for a first rotation cycle for poplar SRCs. The biomass fuel quality was not affected by the slurry treatments. A good performance of plant total height and growth in diameter at breast height suggested that poplar trees were not stressed by the applied slurry. Only treatment T1 could assure that cattle CO₂-eq methane emissions were overall equilibrated by the carbon sequestration from poplar cultivation, with an absence of climatic-warming impacts. Treatments T2 and T3 could only partially minimize that impact, which would always exist. Globally, this site-specific analysis showed that, under moderately fertile conditions, controlled cattle slurry fertilization of poplar SRC cultivations, which would assure a long-term steady-state equilibrium, can be a viable option to contribute to decentralized production of bioenergy in rural communities. Full article

The aim of this study was to evaluate the effect of foliar application of selected micro-nutrients on the chemical composition and malting quality of spring barley (Hordeum vulgare L.). The scientific literature lacks in-depth studies that assess the effect of foliar application of micronutrients on barley malting quality. Most studies (especially under field conditions) focus on nitrogen fertilization rather than individual micronutrients. Three brewing-type barley cultivars (Baryłka, KWS Irina, and RGT Planet) were evaluated under foliar micronutrient fertilization (Cu, Mn, Mo, Zn). Fertilizers were applied at doses of 2 L ha⁻¹ for Cu, Mn, and Zn and 1 L ha⁻¹ for Mo. The experiment examined the hectoliter mass, theoretical extractability, contents of selected micro- and macronutrients, and the protein, fat, fiber, and ash contents of the grain. Furthermore, the following characteristics of barley malt were determined, i.e., moisture, protein, extractivity, Kolbach index, and diastatic power. The results showed significant variability in grain and malt quality depending on the cultivar and year. The Baryłka cultivar was characterized by the highest grain density (66.3 kg hL⁻¹) and protein content (10.9% d.m.), while RGT Planet had the highest extractivity and the most favorable malting profile. Foliar supplementation had a slightly positive effect on the average content of trace elements in barley. Mn application increased grain Ca content by 5.6% compared with the control, while foliar Zn fertilization resulted in the highest zinc concentration (a 24.7% increase). No significant effect of fertilization on malt quality was observed, but a significant interaction of experimental factors in extractivity, Kolbach index, and diastatic power was noted. The obtained results indicate that a single foliar application of microelements affects the contents of minerals and protein in the grain, but it does not lead to a significant improvement in malting parameters. This suggests the need for further research on dosage, application date, and interactions between the cultivar and environmental conditions. Full article

Hygienization by hydrothermal carbonization (HTC) of chicken manure (CM) at 250 °C allows its valorization as soil amendment or even organic fertilizer. To test if this hypothesis is also valid for feedstocks from free-range breeding, respective material of a small farm in southern Spain was comprehensively chemically characterized. The hydrochar of the manure collected from the ground of the farm was rich in mineral matter. After HTC, 68% of the organic carbon (C) was recovered, whereas 82% of the nitrogen (N) was lost most likely by volatilization and with the discarded process water. Despite this, 2.8% of the total N in the hydrochar was identified as inorganic N (N_i). Solid-state ¹³C and ¹⁵N NMR spectroscopy revealed aromatization of organic C and N, although alkyl C and amide N still contributed with 23% and 35% to the total organic C and N, respectively. The obtained distribution of N-forms indicated that enough N_i is plant-available for early plant growth, while the remaining N occurs in structures that can be slowly mobilized during advanced plant development. Low heavy metal concentrations suggest low phytotoxicity. Pot experiments with lettuce, sunflower, and tomato plants confirmed species- and dosage-dependent effects. A dosage of 3.25 t ha⁻¹ improved lettuce and sunflower yields, whereas a dosage of 6.5 t ha⁻¹ provided no additional growth benefits but caused phytotoxic reactions of the tomato plants. Our results support HTC as a strategy to valorize CM from free-range farms, although, due to the high variability of such materials, we recommend a thorough chemical characterization and phytotoxic tests before its application. Full article

Environmental impacts of urban wastewater treatment plants (WWTPs) can be reduced by recovering nutrients and organic matter (OM) from their streams for agricultural use, decreasing dependence on conventional fertilizers. This study evaluated dehydrated sewage sludge (SS) as an organic amendment and the partial replacement of mineral P fertilizers in lettuce cultivation. Struvite, a byproduct of WWTPs, was also investigated as a sustainable P source. A 43-day greenhouse pot experiment assessed SS (12 t/ha) and struvite (at two P rates: 30 and 60 kg P₂O₅/ha), both alone and combined. SS significantly increased soil OM (p < 0.001), though long-term applications would be required to enhance this effect. The highest struvite rate (60 kg P₂O₅/ha) yielded the greatest extractable soil-P levels (150 ± 8.1 mg P₂O₅/kg), while its combination with SS further increased extractable P (>250 mg P₂O₅/kg), indicating a stable soil P pool. The highest plant dry biomass (8.9 ± 1.1 g, p < 0.05) also occurred under the highest struvite dosage. Complementary effects between SS and struvite were observed in foliar K, Ca, Mg, and S contents, although no significant interaction between both was found for P content. Adequate foliar P levels (0.40–0.52%) were achieved only in treatments containing SS, indicating its essential role in improving plant P nutrition. Full article