Search Results (351)

Sustainable agricultural technologies are essential to respond to environmental and social pressures, ensuring the maintenance of global food security. Therefore, there is an urgent demand for more sustainable agricultural practices that promote soil quality, as this factor directly impacts the global economy. Agricultural yield is directly associated with soil health and fertility. The use of organic waste serves as a source of essential nutrients for plants, increasing soil organic matter, contributing to the improvement of soil physical and chemical properties, as well as increasing crop yield. Based on this context, this research aimed to evaluate the effects of incorporating organic waste aiming to mitigate the oxidative damage in maize plants grown under different levels of soil fertility (low, average, and high), evaluating soil and plant, more specifically chemical, physiological, biochemical, and morphological responses. In soil, organic waste promoted significant increases in the activities of arylsulfatase and β-glucosidase and improved the chemical parameters, including cation exchange capacity, soil organic matter, base saturation, and sum of bases. The application of organic waste, regardless of fertility level, improved the nutritional status in maize plants, increased concentrations of photosynthetic pigments, maximized the photochemical efficiency and photosynthesis rate. In plant metabolism, the results demonstrated that organic waste promoted significant increases in plant antioxidant defense, including superoxide dismutase, catalase, ascorbate peroxidase, and peroxidase, minimizing the oxidative stress on photosynthetic machinery, especially in plants cultivated on soil with low fertility. Therefore, this research proves that organic waste mitigates the negative impacts associated with nutritional starvation, improves soil health and fertility, favors the maintenance of redox metabolism, and stimulates photosynthesis in maize plants cultivated in low-fertility soil. Full article

The yield of apple trees as a function of potassium fertilization and the critical levels (CLs) and sufficiency ranges (SRs) of K in the soil, leaves, and fruits were determined in two experiments (two orchards) in four crop seasons. Plants of “Royal Gala” and “Fuji Suprema” cultivars were treated with 0, 50, 100, 150, or 200 kg K₂O ha⁻¹ year⁻¹. Potassium was applied annually during the bud swelling phase and onto the soil surface in the projection of the plant canopy, without incorporation. Critical levels and SR were estimated by Bayesian segmented quantile regression models. The cultivar factor was the main source of variation in fruit yield, K concentration in leaves and pulp, and K exported by apples. The crop season was the second factor with the greatest contribution to apple yield and K concentrations in leaves. When data from all crop seasons and orchards were pooled, yield did not vary by K treatments. The concentration of K in the leaf and fruit pulp also did not change as a function of the K dose with grouped data. For fruit production, the CL of K in the soil was 170 mg dm⁻³ for both cultivars; 17.8 g kg⁻¹ and 15.8 g kg⁻¹ in leaf for “Fuji Suprema” and “Royal Gala”, respectively; 1150 mg kg⁻¹ and 1080 mg kg⁻¹ in fruit pulp for “Fuji Suprema” and “Royal Gala”, respectively. The lack of response to K fertilization indicates that the trees were operating within a nutritional plateau. Consequently, we recommend that K fertilization in subtropical apple orchards be guided strictly by soil and plant analysis. For orchards exceeding the soil critical level of 170 mg dm⁻³ and leaf concentrations of 17.8 g kg⁻¹ and 15.8 g kg⁻¹ in leaf for “Fuji Suprema” and “Royal Gala”, respectively, and 1150 mg kg⁻¹ and 1080 mg kg⁻¹ in fruit pulp for “Fuji Suprema” and “Royal Gala”, respectively, K applications may be reduced or temporarily withheld under similar high-K soil conditions, provided that soil and plant nutritional status are regularly monitored. This management strategy ensures high yields and more efficient and sustainable nutrient management. Full article

Although soil fungi play a crucial role in straw decomposition, mineralization, nutrient cycling, and soil fertility, soil nitrogen and carbon stoichiometry across crop growth stages under long-term straw retention and wheat–soybean rotation remains poorly understood. We assessed the dynamic changes in soil fungal communities under no straw (NS) retention, half straw (HS) retention, and total straw (TS) retention in winter wheat and summer soybean rotation. Compared with the NS treatment, average total nitrogen (TN) increased by 11.86% and 17.71% and mean soil organic carbon (SOC) increased by 4.10% and 13.08% under the HS and TS treatments, respectively. NO₃⁻-N/TN and microbial biomass nitrogen (MBN)/TN ratios increased with the increase in straw retention; NH₄⁺-N/TN and dissolved organic carbon/SOC ratios decreased. Microbial biomass carbon (MBC)/SOC increased and subsequently decreased as straw retention increased. The mean soil C:N ratio increased, and the MBC/MBN ratio decreased as straw retention increased. Crop growth stage and straw retention treatments significantly influenced soil fungal diversity and abundance; while they did not induce changes in the dominant species, they affected relative abundance. Soil fungal relative abundance and community dynamics were more sensitive to crop growth than to straw retention treatments. Mantel’s r statistic and Pearson correlation coefficient suggest that soil chemical stoichiometric ratios are useful indicators of relationships among the fungal community, soil nutrient status, and crop cultivation. Therefore, straw retention may be suitable for long-term wheat–soybean rotation. Full article

Salt stress remains a major global stress factor among abiotic stresses limiting crop production. Salt stress is a major nutritional challenge, with poor agricultural production characterized by high soil sodium (Na⁺) levels in soil and plants. Soil salinity negatively affects plants through both osmotic effects and ionic toxicity. Hence, one of the main aims of agricultural scientists is to develop eco-friendly, sustainable solutions to alleviate soil salinity. Over the past decades, several studies have recommended biochar as a vital sustainable soil amendment to alleviate the negative consequences of soil salinity. Thus, this review builds on the literature on biochar-mediated alleviation of salt stress. Biochar is a carbon-rich material produced from biomass and feedstock via pyrolysis under little or no oxygen conditions. Due to its unique characteristics, such as high carbon, high surface area with porous and aromatic structure, high pH, high stability, cation exchange capacity, and water and nutrient retention capacity, it is considered an alternative for salt stress alleviation. Moreover, biochar facilitates sodium ion (Na⁺) adsorption, reduces Na⁺ uptake, and increases potassium ion (K⁺) uptake, enhancing nutrient cycling, helping plants maintain ionic balance and osmotic regulation. This, in turn, significantly increased the activity and diversity of soil microorganisms, enhanced their adhesion, and promoted their growth, thereby strengthening the plant’s salt resistance. Moreover, biochar-mediated improvements in microbial community dynamics and changes in the physical and biological properties of soil contribute to overall plant and soil health under salt stress. Hence, the present review aims to decipher the holistic patterns of biochar on soil and plant health, changes in physiological and defense mechanisms, plant hormones and signaling mechanisms, and the status of modified biochar under salt stress. Thus, the present review will pave the way for the production of salt-resilient crops with enhanced salinity tolerance. In conclusion, the use of biochar-based fertilizers and modified biochar enhanced microbial community dynamics in soil health homeostasis and soil fertility for agricultural production and food security. Full article

Soil quality is a critical determinant of crop productivity. This study assessed the soil quality of 61 barley farmlands in central and northern Hubei Province based on ten soil chemical properties: pH, soil organic matter (SOM), ammonium nitrogen (NH₄⁺-N), nitrate nitrogen (NO₃⁻-N), hydrolyzable nitrogen (HN), available phosphorus (AP), available potassium (AK), exchangeable calcium (Exc-Ca), exchangeable magnesium (Exc-Mg), and available sulfur (AS). A total of 68.85% of the farmlands were acidic (pH < 6.5). The average levels of SOM, NH₄⁺-N, NO₃⁻-N, and HN were deficient, while AP was moderate, according to the Second State Soil Survey of China (SSSSC). AK, Exc-Ca, Exc-Mg, and AS were, on average, at moderate-to-abundant levels. Differences in preceding crops led to significant differences in pH and SOM between paddy and dryland fields. A minimum data set was established using six soil properties (HN, AS, AK, Exc-Ca, Exc-Mg, and NH₄⁺-N) to calculate the soil quality index (SQI). SQI ranged from 0.27 to 0.69, with an average of 0.45, indicating overall low soil quality in the region. Both accuracy importance and R²-weighted importance revealed that HN was the most influential factor driving SQI variation among the soil properties examined. This study elucidates the status of soil nutrients, offering a diagnostic basis for developing targeted fertilization strategies for barley in this region. Full article

Amino acids are organic compounds that serve as the fundamental building blocks of proteins and are additionally responsible for a multitude of other biological functions. This review synthesizes recent evidence elucidating that amino acids function as vital players in nitrogen transport, stress defense, and perhaps most intriguingly as signaling molecules. For example, glutamate triggers calcium signals through GLR receptors to guide root growth and pollen tubes. Others, like proline and glutathione, protect cells from drought, salt, and oxidative damage. Aromatic and sulfur-containing amino acids also feed into the production of hormones (auxin, ethylene) and a wide range of defense compounds. Beyond metabolism, we highlighted how plants sense amino acid status via ancient sensors such as PII and the TOR pathway, which fine-tune growth and resource allocation. Understanding this hidden side of amino acids opens new doors for agriculture. We discussed how these insights could lead to smarter biostimulants, gene-edited crops with better nutrient efficiency, and nano-based delivery systems. In short, amino acids are not just food for plants—they are signals, shields, and switches that shape how plants grow and cope with stress. Full article

Vermicomposting is an environmentally sustainable, economically viable, and agronomically valuable method for converting organic waste into nutrient-rich soil amendments, thereby supporting sustainable development. However, the fertilization efficiency of vermicompost can vary significantly depending on the physicochemical properties of the feedstock used. This study aims to compare different feedstocks on vermicompost and evaluate their performance on soil fertility and plant nutritional status. Organic matter (OM), pH, salinity (EC), total Kjeldahl nitrogen (TKN), total phosphorus (TP) and total potassium (TK) of various vermicompost samples were taken into consideration to evaluate their fertilization efficiency as performance determinants in terms of plant growth, plant nutritional status, yield, crop quality and cost with the aim of determining the weights of the specific parameters in the total performance using multi-criteria decision-making (MCDM) methods. The integrated ENTROPY-TOPSIS method was used. Twenty-one different vermicompost feedstock analyses were collected from the literature and compared in order to create an agronomic performance ranking based on the selected criteria. The ENTROPY method revealed that the TP was the most influential factor (21.6%), followed by the EC (20.7%) and the TK (18.5%), while the OM had the lowest impact (11.3%). Based on the TOPSIS ranking, vermicompost from brewer’s spent grain achieved the highest performance, followed by cow manure plus rice straw and olive pruning waste, whereas paper waste ranked at the bottom. A comparative analysis with other objective MCDM weighting methods proved strong correlations, particularly with WENSLO, MPSI and LODECI methods, confirming the robustness of the ENTROPY method. Full article

Agroforestry and perennial tree crop production systems, particularly in Mediterranean regions, exhibit a high degree of integration among trees, herbaceous, and soil components. They provide essential services including provisioning, regulation, support, and cultural services, which enhance human health, well-being, and economic stability. However, guaranteeing their long-term resilience in the face of environmental challenges, including drought and soil degradation, is essential for the sustainable management of these systems. We examine the impact of microsite conditions (soil and herbaceous layer) and their management on olive trees (Olea europaea L.) under varying levels of drought stress. A fully factorial design was implemented in a Spanish agroforestry system, combining two irrigation regimes (rainfed vs. summer irrigation) and two soil management practices (customary plowing vs. herbaceous layer conservation) across four independent and replicated zones. Twelve olive trees per zone were individually monitored, treating each tree as the experimental unit, with one 50 × 50 cm sampling plot per tree in which microsite conditions were characterized for each tree. Plowed areas (shallow tillage) showed lower industrial extraction yield (%), fat yield based on dry matter (%), olive maturity and phytosanitary status compared to areas conserving their herbaceous layer cover (0.81, 0.96, 0.92, and 0.65-fold lower, respectively). Rainfed areas (i.e., those without supplemental water supply) showed a reduction in both industrial extraction yield (%), olive yield (kg tree⁻¹) and oil yield (kg ha⁻¹) (0.77, 0.86 and 0.67-fold lower, respectively). Under combined tillage and water-deficit conditions, oil yield (kg ha⁻¹), industrial extraction yield (%), and total phenolic content (ppm) were considerably lower (0.50, 0.60, and 0.67-fold lower, respectively). Furthermore, low quality of the herbaceous layer dominated by nitrophilous invasive species were associated with decreased leaf nutrient content, lower industrial extraction yield, reduced olive maturity and poorer phytosanitary status of olives. These findings suggest that maintaining a spontaneous herbaceous layer with a high-quality species (legume incorporation) and well-managed herbaceous cover, i.e., repeated mowing of the herbaceous layer instead of customary plowing, can enhance sustainable olive production by improving soil resilience, reducing water stress, and optimizing nutrient use, thereby supporting long-term ecosystem stability and agricultural productivity. Full article

Nitrogen (N) management is critical for optimizing growth and fruit quality in open-field strawberry cultivation, demanding advanced technological solutions for reliable nutrient assessment. However, visual symptom diagnosis, though widely utilized for nutrient monitoring, is inherently subjective and prone to observer bias, resulting in inconsistent and often unreliable assessments. While available accurate tissue analysis is destructive and costly. Nondestructive, in-field imaging techniques such as the normalized difference vegetation index (NDVI) exist but require expensive multispectral imaging systems. To address these limitations, this study developed a streamlined methodology for in-field N status detection using deep learning on standard RGB images. The experiment utilized ‘Yotsuboshi’ strawberries in a randomized complete block design with sufficient nitrogen (T1) and deficient nitrogen (T2) treatments. To mitigate ambient light variability, a key challenge in open-field phenotyping, a low-cost phenotyping cylinder was developed for standardized smartphone image acquisition. Rigorous four-stage annotation criteria were also introduced to classify the nitrogen status in strawberry leaves as NormalN, LowN, or AdvancedLowN, ensuring a high-quality novel dataset. A YOLO11 model trained on this dataset achieved precision, recall, and mAP50 values exceeding 99%. Subsequent testing using the phenotyping cylinder yielded a mAP50 of 87%. In-field validation without a phenotyping cylinder also demonstrated robust performance under diffuse cloudy conditions (82.7% mAP50), outperforming direct sunlight (79% mAP50). Moreover, the model’s classifications of ‘NormalN’ and ‘LowN’ statuses strongly corresponded with NDVI measurements, validating the accuracy of the RGB-based approach. This research demonstrates the significant potential of combining deep learning and phenotyping cylinder to create a rapid, low-cost, nondestructive and reliable tool for in-field nitrogen detection, with possible application across different crops and environmental conditions. Full article

Nitrogen (N) is a key nutrient for upland rice (Oryza sativa L.), and plant growth-promoting rhizobacteria (PGPR) have been investigated as a sustainable strategy to improve plant nutrition and crop performance. This study evaluated the effects of N topdressing and PGPR inoculation on leaf chlorophyll index (LCI), leaf nutrient concentrations, and yield components in upland rice. A field experiment was conducted in a randomized block design (4 × 6 factorial) with four N rates (0, 40, 80, and 120 kg ha⁻¹) and five PGPR strains (Azospirillum brasilense, Nitrospirillum amazonense, Bacillus subtilis, Priestia aryabhattai, and Methylobacterium symbioticum), plus a non-inoculated control. No significant interaction between N rates and PGPR inoculation was observed. Nitrogen increased leaf phosphorus (P), potassium (K), and magnesium (Mg) concentrations and panicle number; however, it also increased unfilled grains, reduced grain weight, and did not affect grain yield. Azospirillum brasilense increased LCI by 25.7%. Bacillus subtilis and A. brasilense increased leaf N, K, Mg, copper (Cu) and manganese (Mn) concentrations. Azospirillum brasilense, B. subtilis, N. amazonense, and P. aryabhattai reduced unfilled grains, increased grain weight and grain yield by up to 10.7%, whereas M. symbioticum did not differ from the control in grain yield. Under the conditions of this study, nitrogen was not limiting for grain yield, and all strains, except M. symbioticum, were associated with increases in grain yield and changes in plant nutritional status. Full article

Cytokinin (CK) is a central regulator of plant development, yet its roles cannot be understood fully without considering how CK signaling was assembled during evolution and redeployed in different physiological contexts. In this review, we examine how prokaryotic two-component modules were elaborated into the land–plant CK system and how this system now integrates biosynthesis, transport, receptor selectivity, and feedback control to shape developmental and symbiotic outcomes. We argue that three recurring interpretive dimensions are especially useful for organizing current evidence: compartmentalized CK pools, context-dependent decoding of local CK availability, and the coupling of local CK responses to whole-plant nutrient status. These dimensions help organize current observations on why CK effects in arbuscular mycorrhiza (AM) are often conditional and readout-dependent, whereas evidence from legume–rhizobium symbiosis supports a more direct role for CK in cortical competence, nodule organogenesis, and autoregulation of nodulation. Rather than treating CK as a generic positive regulator of symbiosis, we propose that it functions as a spatially partitioned and nutritionally gated integrator whose outputs depend on cell type, developmental stage, transport route, and resource context. We conclude by highlighting key mechanistic gaps—particularly in transporter-resolved CK partitioning and systemic integration—and by outlining experimentally testable priorities for translating CK biology into crop improvement. Full article

Silicon is increasingly applied in agriculture to improve plant productivity under both abiotic and biotic stress constraints. Nevertheless, its mechanisms of action are often studied separately at the soil, plant, or microbiome levels, limiting a comprehensive understanding of its overall impact on agroecosystem functioning. This review proposes an integrated perspective of the soil–plant–microbiome continuum, linking silicon chemistry in soil solutions with the effects of silicon amendments on soil properties and the processes of uptake, transport, and deposition in the plants. We show that silicon bioavailability depends on maintaining a pool of dissolved silicon dominated by orthosilicic acid, regulated by mineral weathering, adsorption–desorption dynamics, polymerization, pH, iron and aluminum oxides, and organic matter. In soils, silicon inputs can improve structure, modulate acidity and cation exchange balances, influence nutrient availability, and reduce the mobility of certain metals. They may also affect enzymatic activities and microbial community composition. In plants, silicon uptake and transport, mediated by specific transporters, contribute to tissue silicification, the maintenance of leaf architecture, and the regulation of water, ionic, and redox homeostasis. These processes provide a basis for enhanced tolerance to drought, salinity, and metal toxicity, as well as biotic stress caused by pathogens and pests. Finally, we discuss key limitations to the agronomic application of silicon, including the diagnosis of the silicic status of soils, the choice of source and mode of application, and the genotypic variability of acquisition, as well as the need for multi-site tests and more robust mechanistic validations. This synthesis provides a coherent mechanistic framework to better define the conditions under which silicon can serve as a reliable tool for sustainable crop management under climate change. Full article

Climate change-induced variability in temperature and precipitation increasingly constrains crop production on sandy-textured soils with low water-holding capacity and limited nutrient retention. Such soils, classified as Brunic Arenosols, are widespread across the temperate climate zone of Central Europe, particularly in post-glacial landscapes, where they constitute a significant proportion of marginal agricultural lands. This study evaluated the relative influence of growing-season weather conditions and selected soil physicochemical properties on the yield of Camelina sativa and Brassica carinata cultivated under low-input management on Brunic Arenosols in northwestern Poland during the 2023 season. Yields varied markedly among sites. Camelina sativa produced yields from 300 to 930 kg ha⁻¹, with the highest yield recorded at the site characterized by higher BS and phosphorus availability. Brassica carinata produced yields from 0 to 370 kg ha⁻¹, including complete yield loss at one location due to severe pathogen infestation. Spearman’s correlation analysis revealed that temperature was a key determinant for both crops (r = 0.77 for C. sativa; r = 0.82 for B. carinata). For Camelina sativa, yield was strongly associated with BS (r = 0.80) and available P (r = 0.69), whereas Brassica carinata was more sensitive to climatic variability, showing a negative relationship with precipitation (r = −0.63). The results indicate species-specific responses to soil fertility and weather conditions under water- and nutrient-limited conditions typical of Central European sandy soils. While Camelina sativa performance was more closely linked to soil chemical status, Brassica carinata appeared predominantly climate-driven. These findings highlight the broader relevance of the study for temperate regions of Central Europe and support the integration of soil fertility management with climate-adaptive strategies when introducing alternative oilseed crops to marginal lands. Full article

Successive cropping frequently causes a decline in Chinese Fir (Cunninghamia lanceolata) biomass, a problem intricately tied to soil nutrient shifts and microbial processes. This research investigates the mechanisms governing biomass carbon partitioning and soil nutrient shifts in these plantations. This study investigated five Chinese Fir clones (‘ck’, ‘b44’, ‘K13’, ‘F13’, and ‘kt13’) across two cultivation regimes: continuous cropping (second-generation plantation, G2) and first-generation plantation (G1). The focus was on their biomass and soil nutrient status. The results showed that: (1) The biomass of different Chinese Fir clones at 25 years of age decreased significantly with increasing generations of continuous cultivation. Tree height showed no significant differences among clones within the same generation; however, the G2 cultivation significantly inhibited diameter at breast height (DBH). (2) The changes in soil nutrients and microbial activity under different successive generations (G1, G2) was closely linked to the decline in Chinese Fir biomass carbon. Analysis revealed that the decreases in dissolved organic carbon (DOC), dissolved organic nitrogen (DON), and Catalase (CAT) activity were significantly positively correlated with the reduction in biomass carbon. Concurrently, the decrease in soil pH showed a significant negative correlation with microbial biomass carbon (MBC) and Sucrase (SUC) activity. (3) Regarding growth traits, although tree height showed no significant differences among clones within the same generation, DBH was generally and significantly inhibited under G2 cultivation. An exception was the ‘K13’ clone, which remained largely unaffected. In terms of carbon accumulation, G2 cultivation led to a universal decline in biomass carbon across clones; however, the magnitude of reduction in different components (leaf, branch, stem, root) and total biomass carbon varied clone-specifically. Notably, ‘K13’ exhibited the strongest tolerance, with a significantly smaller decrease in tree biomass carbon compared to the other four clones, which showed substantially lower tree carbon stocks across all components relative to G1 plantations. This indicates that successive cropping of Chinese Fir likely constrains the carbon sequestration capacity of plantations by altering soil nutrient properties, thereby suppressing tree DBH growth and biomass carbon accumulation, likely through reduced net primary productivity. Among the five clones, ‘K13’ was the least affected, demonstrating its high potential for adaptation to continuous cultivation. These findings provide implications for sustainable forest management by guiding clone selection to mitigate productivity decline under successive cropping. Full article

Increasing domestic sewage production associated with urban population growth poses environmental challenges. Biosolids from wastewater treatment can recycle nutrients in agriculture, while plant growth-promoting rhizobacteria (PGPR) enhance nutrient availability and plant performance. This study evaluated the effects of the combined application of sewage sludge–derived biosolid and Bacillus aryabhattai on sunflower growth, biomass production, physiological traits, and nutrient status during the early growth stage under greenhouse conditions. We hypothesized that this combined treatment would enhance plant performance compared with biosolid application alone. Four treatments were established: control (T1), 5 g of biosolid alone (T2), 5 g biosolid + 3.2 mL B. aryabhattai (T3), and 5 g biosolid + 6.4 mL B. aryabhattai (T4). The formulation contains B. aryabhattai strain CMAA 1363 (1 × 10⁸ CFU mL⁻¹) as the active microbial component, together with humic substances and other formulation agents (thickener, preservative, and water). The Plants were grown for 44 days. The data were analyzed using one-way ANOVA followed by mean comparison among treatments. Shoot dry mass was significantly higher in T4 compared with the T1 and T2 (p < 0.001), while no significant difference was observed between T3 and T4 (p > 0.05). Biosolid application increased the photosynthetic rate, and its combination with B. aryabhattai further enhanced photosynthetic performance, with significant difference detected between bacterial doses only at the end of growth period. Substomatal CO₂ concentration was lower in inoculated treatments, indicating greater CO₂ assimilation efficiency. Total chlorophyll increased with the addition of sludge and further increased by inoculation with 6.4 mL. Leaf N, Mn, and Zn contents were highest in T4. Overall, the combined application of biosolid and B. aryabhattai improved photosynthetic efficiency and biomass accumulation, highlighting the potential of integrating biosolids and beneficial rhizobacteria as a sustainable approach for nutrient recycling and improved crop productivity in agricultural systems. Full article