Agronomy

30 pages, 2036 KB

Open AccessArticle

Temporal Emergence and Slope Dependence of RUSLE-Based Erosion Reduction Associated with Cropland Abandonment in Northeast China’s Black Soil Region

by Wei Song

Agronomy 2026, 16(19), 1881; https://doi.org/10.3390/agronomy16191881 - 24 Sep 2026

Abstract

Cropland abandonment is expanding, but the timing and slope dependence of modelled erosion contrasts and residual soil loss remain poorly resolved. The study reconstructed continuous abandonment in Northeast China’s black soil region using 30 m annual land cover data (2000–2023) and 30 m [...] Read more.

Cropland abandonment is expanding, but the timing and slope dependence of modelled erosion contrasts and residual soil loss remain poorly resolved. The study reconstructed continuous abandonment in Northeast China’s black soil region using 30 m annual land cover data (2000–2023) and 30 m RUSLE-based water erosion estimates (2000–2020), with local contemporaneous continuously cultivated controls. By 2020, land with event-time Age >10 represented 48.91% of continuously abandoned cropland. The relative reduction metric was small and uncertain at the cropland-exit event anchor (Age 1; 2.13%), reached 40.56% in the first complete post-exit year (Age 2), and remained at 47–50% during Ages 4–17. The operational stable reduction criterion was met earlier on 0–5° slopes than on steeper land, where early and long-term contrasts were weaker. Across 6040 10 km × 10 km cells with continuous abandonment, model-based residual loss totalled 1.090 × 10⁶ t yr⁻¹. Unadjusted 15 km Getis–Ord Gi* hot spots at ≥95% confidence occupied 15.0% of all cells but contained 55.5% of residual loss; two high-loss zones occupied 22.20% of abandonment-containing cells but contained 64.9% of residual loss. Continuous abandonment was associated with lower modelled hillslope water erosion without eliminating absolute pressure. Because regional field validation was unavailable, priorities for recently abandoned moderate-to-steep slopes and high-loss areas remain indicative pending field confirmation. Full article

(This article belongs to the Special Issue Land Degradation and Management Strategies: Contributing to Sustainable Agriculture—2nd Edition)

21 pages, 1188 KB

Open AccessArticle

Time-Course Evaluation of Water and Fertilizer Use Efficiencies and Growth Characteristics of Lettuce Cultivated Under Artificial Light Using a One-Way, Reduced-Discharge Hydroponic Cultivation Unit

by Yumiko Amagai, Toru Maruo, Akimasa Nakano and Eri Hayashi

Agronomy 2026, 16(19), 1880; https://doi.org/10.3390/agronomy16191880 - 24 Sep 2026

Abstract

The recirculating flow hydroponic cultivation unit (RFC) used in plant factories with artificial lighting requires nutrient solution replacement to prevent growth inhibition caused by nutrient imbalances and allelochemical accumulation. Although sustainable systems are needed to reduce environmental impacts, the effects of non-flowing conditions [...] Read more.

The recirculating flow hydroponic cultivation unit (RFC) used in plant factories with artificial lighting requires nutrient solution replacement to prevent growth inhibition caused by nutrient imbalances and allelochemical accumulation. Although sustainable systems are needed to reduce environmental impacts, the effects of non-flowing conditions on plant growth and nutrient uptake dynamics remain unclear. We used a one-way, reduced-discharge hydroponic cultivation unit (ORC) to evaluate frill-type lettuce growth and quantify changes in water use efficiency (WUE), fertilizer use efficiency (FUE), and inorganic nutrient absorption under non-flowing conditions. The ORC reduced nutrient solution uptake by ~28% compared with the RFC, improving physiological and system-level WUE and FUE. Root dry weight in the ORC was ~1.5 times higher, likely owing to morphological adaptation—specifically, enhanced root system development—that expanded the nutrient acquisition area under reduced diffusion. Fluid movement in the RFC may also have physically inhibited root growth. Conversely, initial growth in the ORC was lower because of reduced nutrient supply to the rhizosphere. Overall, the ORC achieved high WUE and FUE while minimizing waste. Quantifying the time-course absorption characteristics of inorganic components in this unit is expected to enable precise adjustment of individual nutrients, further reduce discharge, and facilitate high-quality production. Full article

(This article belongs to the Section Innovative Cropping Systems)

14 pages, 3902 KB

Open AccessArticle

Antifungal Activity of Leaf Essential Oil and Its Endophytic Fungi of Camphora bodinieri with Citral Chemotype Against Rhizoctonia solani

by Yamin Liu, Youxiang Wu, Qingyan Ling, Rong Zeng, Lina Huang, Teng He, Zhinong Jin, Faxin Yu and Beihong Zhang

Agronomy 2026, 16(19), 1879; https://doi.org/10.3390/agronomy16191879 - 24 Sep 2026

Abstract

This study aimed to investigate the inhibitory effects and mechanisms of essential oil and its endophytic fungi of Camphora bodinieri with citral chemotype (CBCC) against Rhizoctonia solani, the causal agent of rice sheath blight. The antifungal activity was assessed by measuring the [...] Read more.

This study aimed to investigate the inhibitory effects and mechanisms of essential oil and its endophytic fungi of Camphora bodinieri with citral chemotype (CBCC) against Rhizoctonia solani, the causal agent of rice sheath blight. The antifungal activity was assessed by measuring the inhibition rate at various concentrations. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to observe ultrastructural changes in the pathogen. For the CBCC bodinieri essential oil treatment group, the MIC was 1.0 μL/mL, and the inhibition rate reached 100%, showing a concentration-dependent effect (0.0625–1.0 μL/mL, inhibition rate 29.02–100%). Electron microscopy showed that the essential oil caused severe damage to hyphal cell membranes, cytoplasmic agglutination, and organelle disintegration, whereas the endophytic fungi caused only local shrinkage and partial deformation. Both the CBCC essential oil and the endophytic fungi exhibit antifungal activity. They are promising candidates for the biological control of rice sheath blight and have potential for development as biofungicides. Full article

(This article belongs to the Section Farming Sustainability)

► Show Figures

Figure 1

23 pages, 16107 KB

Open AccessArticle

Optimizing Brackish Water Irrigation Scheduling for Honeysuckle (Lonicera japonica Thunb.): Reconciling the Trade-Off Between Yield and Chlorogenic Acid Accumulation

by Yu Shi, Ran Yi, Wenjun He, Dongjie Zhang, Jiangbao Xia, Wendi Qu, Xiaojie Wang, Xuesong Ma and Xiaoshuai Zhang

Agronomy 2026, 16(19), 1878; https://doi.org/10.3390/agronomy16191878 - 24 Sep 2026

Abstract

While brackish-water irrigation alleviates freshwater scarcity in coastal saline agriculture, its optimization for medicinal crops demands balancing yield and bioactive compounds. This study established a quality–yield decision framework for honeysuckle in the Yellow River Delta via a two-year field experiment with four per-event [...] Read more.

While brackish-water irrigation alleviates freshwater scarcity in coastal saline agriculture, its optimization for medicinal crops demands balancing yield and bioactive compounds. This study established a quality–yield decision framework for honeysuckle in the Yellow River Delta via a two-year field experiment with four per-event irrigation amounts: 0 (W1), 40 (W2), 80 (W3), and 120 mm (W4). Soil properties, yield, and medicinal quality were measured. The incremental honeysuckle quality-yield brackish water productivity (ΔHQYP) was calculated, while Entropy-weighted Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) was used to generate comprehensive scores integrating yield, quality, and soil. Results showed that irrigation reduced root-zone salinity but increased pH and decreased nitrate nitrogen and available potassium, with interannual variation. Chlorogenic acid content peaked at 80 per-event mm (W3) and declined at 120 per-event mm (W4), mirroring the honeysuckle quality index (HQI) pattern, while yield peaked at 120 mm, revealing a mismatch between yield and quality optima. Regression analysis indicated that ΔHQYP was co-regulated by soil water content and salinity, not by single factor. By combining TOPSIS scores with coefficients of variation and stability, 80 mm was identified as the preliminary optimal among the tested levels based on data collected over two years spanning three flowering periods. This level optimally balanced desalination, nutrient maintenance, yield, and bioactive accumulation, and is thus recommended. This framework shifts management from yield maximization toward quality-integrated, multi-objective decision-making for medicinal agriculture. Full article

(This article belongs to the Section Water Use and Irrigation)

► Show Figures

Figure 1

20 pages, 19294 KB

Open AccessArticle

Physiological and Transcriptomic Responses of Two Upland Cotton Genotypes to Contrasting Daylength Regimes

by Ning Zhang, Yujie Liu, Yuli Lu, Zhonghua Zhou, Aiyu Liu and Xiaoju Tu

Agronomy 2026, 16(19), 1877; https://doi.org/10.3390/agronomy16191877 - 23 Sep 2026

Abstract

Photoperiod is a crucial environmental factor that regulates plant growth and flowering. While the photoperiodic flowering pathway has been extensively studied, the mechanisms underlying photoperiodic regulation of cotton (Gossypium hirsutum L.) growth and development remain unclear. In this study, we selected two [...] Read more.

Photoperiod is a crucial environmental factor that regulates plant growth and flowering. While the photoperiodic flowering pathway has been extensively studied, the mechanisms underlying photoperiodic regulation of cotton (Gossypium hirsutum L.) growth and development remain unclear. In this study, we selected two cotton genotypes, XJ12 and XJ21-11, to investigate the effects of long-day (LD) and short-day (SD) conditions on cotton photosynthesis, dry matter accumulation, flowering time, and related gene expression, utilizing physiological index measurements, transcriptomics, and WGCNA. The results indicated that LD treatment significantly enhanced photosynthetic parameters and dry matter weight in both cotton varieties, with the net photosynthetic rate (Pn) being 154.79% and 111.86% higher under LD compared to SD treatment. Additionally, the flowering time of the two varieties was advanced by 12 and 13 days, respectively, under LD treatment relative to SD treatment. Transcriptome analysis revealed that LD treatment upregulated the expression of genes involved in sucrose and starch metabolism, consistent with the enhanced growth observed under LD conditions. In addition, LD treatment altered the expression of genes associated with flavonoid biosynthesis, suggesting changes in secondary metabolism. Differentially expressed genes and co-expression networks were also associated with phytohormone signaling, MAPK signaling, and circadian rhythm-related pathways, with several transcription factors identified as potential regulatory components. Together, these findings suggest a putative regulatory framework in which photoperiod-responsive changes in carbon metabolism, secondary metabolism, circadian regulation, and hormone-related signaling are associated with the coordination of cotton growth and flowering. This study provides candidate pathways and regulatory genes for further investigation of the molecular basis of photoperiodic responses in cotton. Full article

(This article belongs to the Special Issue Physiological and Molecular Mechanisms Underlying Crop Growth, Development and Stress Adaptation Regulated by Light Environment)

► Show Figures

Figure 1

26 pages, 2878 KB

Open AccessArticle

Feasibility of Co-Composting Sewage Sludge with Vine Pruning Residues for Sustainable Waste Management

by Henda Lopes, Elisabete Nascimento-Gonçalves, Tiago Azevedo, Cristina Morais, Virgílio Falco, Ana Claúdia Coelho, Ana Coimbra, João Ricardo, Paula A. Oliveira, Henrique Trindade and Marta Roboredo

Agronomy 2026, 16(19), 1876; https://doi.org/10.3390/agronomy16191876 - 23 Sep 2026

Abstract

The increasing generation of sewage sludge (SS) and the accumulation of agricultural residues such as vine pruning residues (VPR) represent significant environmental challenges, including pollution risks and resource underutilization. Composting offers a sustainable strategy to transform these wastes into high-quality compost, facilitating resource [...] Read more.

The increasing generation of sewage sludge (SS) and the accumulation of agricultural residues such as vine pruning residues (VPR) represent significant environmental challenges, including pollution risks and resource underutilization. Composting offers a sustainable strategy to transform these wastes into high-quality compost, facilitating resource recovery within a circular framework. This study aimed to evaluate the feasibility of co-composting SS with VPR as a strategy for organic waste valorization. Two mixtures were prepared using cattle slurry solid fraction (CS) as inoculum, M1 (50% SS + 30% VPR + 20% CS) and M2 (30% SS + 50% VPR + 20% CS). The results showed that both mixtures exhibited typical composting temperature profiles, with the thermophilic phase effectively eliminating Salmonella and E. coli, confirming adequate hygienization. Macronutrient concentrations were consistently higher in M1 (N: 43.44, P: 12.41, and K: 25.27 g kg⁻¹ DW) than in M2 (N: 32.14, P: 8.57, and K: 23.66 g kg⁻¹ DW). All potentially toxic elements remained below the regulatory thresholds established by Ordinance No. 185/2022. Compost maturity was confirmed in both treatments by final C/N ratios below 20, holocellulose/lignin ratios below 1.8, N-NH₄⁺ concentration below 300 mg kg⁻¹ FW (only M2 satisfied this criterion), and N-NH₄⁺/N-NO₃⁻ below 3. However, M2 achieved a very stable respiration rate of 1.95 mg CO₂ g⁻¹ OM d⁻¹ and a germination index of 90.22%, while M1 recorded a respiration rate of 2.38 mg CO₂ g⁻¹ OM d⁻¹ and a lower germination index of 74%. The findings suggest that while M1 is a superior source of macronutrients, M2 provides a more stable and less phytotoxic organic amendment, with both being safe for agricultural soil application. Full article

(This article belongs to the Special Issue Bio-Based Fertilizers and Soil Health: Innovations for Nutrient Recycling and Environmental Protection)

► Show Figures

Figure 1

18 pages, 3556 KB

Open AccessArticle

Comparable Yield Performance of Drought-Tolerant and Conventional Maize Hybrids Under Contrasting Water Management

by Gaetano R. Pesce, Giorgia Raimondi, Maria Giordano, Antonio C. Barbera, Vittoria Giannini, Elisa Marraccini and Carmelo Maucieri

Agronomy 2026, 16(19), 1875; https://doi.org/10.3390/agronomy16191875 - 23 Sep 2026

Abstract

Climate change has intensified plant water stress due to rising temperatures and irregular rainfall, which often fails to meet crop water requirements. Consequently, irrigation has become essential for optimizing the yield of drought-sensitive crops such as maize. Drought-tolerant (DT) maize hybrids represent a [...] Read more.

Climate change has intensified plant water stress due to rising temperatures and irregular rainfall, which often fails to meet crop water requirements. Consequently, irrigation has become essential for optimizing the yield of drought-sensitive crops such as maize. Drought-tolerant (DT) maize hybrids represent a promising strategy to increase resilience under water-limited conditions. This study evaluated the qualitative, morpho-physiological traits, and yield of six maize hybrids, comprising one drought-tolerant (DT) and one conventional (Conv) hybrid for each of three maturity classes (FAO 300, 400, and 500), in Veneto, northeastern Italy. Hybrids were grown under rainfed and fully irrigated conditions. Irrigated plots received 51.7% more water than the rainfed ones. Irrigation increased plant height by 20.4%. At full development, irrigation raised the plant dry weight by 19.7% and ear weight by 24.7%, relative to rainfed management. At harvest time, the grain yield was 48.7% higher under irrigation than under rainfed conditions. No significant effect of drought tolerance was observed on grain yield. Rainfed maize produced grain with higher protein content. Grain from the DT hybrids had lower protein but higher oil content than grain from the Conv hybrids. Therefore, in environments characterized by high temperatures and irregular but not extremely limiting rainfall, management strategies that secure adequate water supply during the reproductive stages remain more effective for sustaining maize productivity than the sole adoption of DT hybrids. These findings should be confirmed through multi-year, multi-site experiments covering a wider range of water availability conditions. Full article

(This article belongs to the Section Innovative Cropping Systems)

► Show Figures

Figure 1

27 pages, 8356 KB

Open AccessArticle

Modified Biochar-DNDC Model Reveals Water–Carbon–Nitrogen Cycling Responses to Biochar Amendment in Paddy Fields

by He Wang, Luguang Liu, Wei Dong, Dongguo Shao, Xiaowei Yang, Rui Zhang, Linhua Ma, Jie Huang, Shaobin Pan, Xuhua Hu and Mei Zhu

Agronomy 2026, 16(19), 1874; https://doi.org/10.3390/agronomy16191874 - 22 Sep 2026

Abstract

Flooded rice paddies emit large quantities of greenhouse gases, and biochar amendment serves as a promising strategy to conserve water, sequester carbon, mitigate emissions and stabilize crop yields. Nevertheless, the DNDC (DeNitrification-DeComposition) model has no specific biochar module and fails to precisely quantify [...] Read more.

Flooded rice paddies emit large quantities of greenhouse gases, and biochar amendment serves as a promising strategy to conserve water, sequester carbon, mitigate emissions and stabilize crop yields. Nevertheless, the DNDC (DeNitrification-DeComposition) model has no specific biochar module and fails to precisely quantify coupled water–carbon–nitrogen cycles in biochar-amended paddies. Using two-season field observations from the Jianghan Plain, this study constructs the Biochar-DNDC model by introducing biochar pH and substrate adsorption parameters into the original organic fertilizer module and coupling a double-tank exponential decay model. Five biochar application rates (0, 1.5, 3, 4.5, and 6 kg∙m⁻²; CK, BC1.5, BC3, BC4.5, BC6) were set. Combined with the 40-year historical precipitation series of the study area, five hydrological year types were classified to carry out multi-scenario simulations. The results indicated that, compared with DNDC, Biochar-DNDC improved the simulation accuracy by an average of 28.4%. In terms of RRMSE, Biochar-DNDC improved the simulation accuracy of yield, SOC, CH₄, and N₂O by 37.0%, 28.7%, 28.6%, and 42.1%, respectively. Environmental temperature, precipitation, soil bulk density, optimal rice yield, and the proportion of straw returned to the field were key sensitive factors regulating water–carbon–nitrogen fluxes. Biochar reduced irrigation water use by 6.3~28.5% while promoting the accumulation of soil carbon stocks, optimizing nitrogen-use efficiency, and suppressing greenhouse gas emissions. There was a significant interaction between rainfall regime and biochar: DOC and NH₄⁺-N were higher in wet years, while NO₃⁻-N tended to accumulate in arid conditions. Biochar weakened the positive driving effect of precipitation on net primary productivity (NPP). Rice yield, NPP, and net ecosystem exchange (NEE) first increased and then decreased with increasing biochar dosage. Overall, the optimal dosage of biochar for water conservation, carbon sequestration, yield increases, and emission reductions in paddy fields on the Jianghan Plain was 4.5 kg∙m⁻². This study develops a modeling tool for the carbon and nitrogen cycles in biochar-amended paddy fields, which can provide quantitative support for low-carbon water and fertilizer management in the rice-growing regions of the middle Yangtze River Basin. Full article

(This article belongs to the Special Issue Enhancing Nitrogen Use Efficiency in Major Crops: Mechanisms, Management, and Synergies with Yield Formation)

► Show Figures

Figure 1

20 pages, 7275 KB

Open AccessArticle

Genome-Wide Association Study and Candidate Gene Prediction of Copper Content in Wheat Grain

by Zhankui Zeng, Xueyan Jing, Qunxiang Yan, Yue Zhao, Junge Bi, Chang Liu, Jiabao Zhang, Xuechun Huang, Xinyi Tang and Chunping Wang

Agronomy 2026, 16(19), 1873; https://doi.org/10.3390/agronomy16191873 (registering DOI) - 22 Sep 2026

Abstract

Copper is an essential trace element in humans, and copper deficiency can compromise health. Wheat is a major staple crop worldwide, and biofortification of wheat grain with copper is a cost-effective strategy to help alleviate dietary copper deficiency. However, the genetic basis of [...] Read more.

Copper is an essential trace element in humans, and copper deficiency can compromise health. Wheat is a major staple crop worldwide, and biofortification of wheat grain with copper is a cost-effective strategy to help alleviate dietary copper deficiency. However, the genetic basis of grain copper content in wheat remains poorly understood. Here, grain copper content was evaluated in 225 wheat accessions, and a genome-wide association study (GWAS) was performed using the Wheat 660 K SNP array. In total, 146 significant SNPs were identified, mainly on chromosomes 2A, 3A, 3B, and 4A. Haplotype analysis indicated that GCuC_2A_Hap, GCuC_4A.1_Hap, and GCuC_4A.2_Hap are key loci associated with grain copper content and show a significant pyramiding effect. Based on bioinformatics and haplotype analysis, TraesCS2A02G549200, TraesCS2A02G550300, TraesCS2A02G550800, TraesCS4A02G305300, and TraesCS4A02G305400 were proposed as candidate genes regulating grain copper content. These results clarify the genetic architecture of grain copper content in wheat and provide a valuable foundation for developing germplasm with elevated grain copper content for wheat quality improvement breeding. Full article

(This article belongs to the Section Crop Breeding and Genetics)

► Show Figures

Figure 1

31 pages, 3638 KB

Open AccessArticle

Integrating Farmers’ Perceptions and Crop Modelling to Evaluate Agronomic Adaptation Measures for Irrigated Maize Under Climate Change

by Daniela Soares, Paula Paredes, Teresa A. Paço, Helder Fraga, João A. Santos and João Rolim

Agronomy 2026, 16(19), 1872; https://doi.org/10.3390/agronomy16191872 (registering DOI) - 22 Sep 2026

Abstract

Farmers’ knowledge is critical for identifying agronomic adaptation measures (AAMs) to cope with climate change. A farmer-informed approach was used to select AAMs. Farmers’ perceptions were collected through a semi-structured survey involving 50 farmers, and the most frequent AAMs were evaluated using the [...] Read more.

Farmers’ knowledge is critical for identifying agronomic adaptation measures (AAMs) to cope with climate change. A farmer-informed approach was used to select AAMs. Farmers’ perceptions were collected through a semi-structured survey involving 50 farmers, and the most frequent AAMs were evaluated using the AquaCrop-OSPy model. Simulations covered a baseline (1971–2000) and future period (2041–2070) under two SSP climate scenarios. Four AAM groups were assessed against the standard cropping system: (i) shorter and longer crop cycles; (ii) earlier sowing dates; (iii) variations in sowing density; and (iv) improved irrigation efficiency. The first three AAM groups were directly simulated, while the fourth was incorporated during post-processing. Evaluation considered irrigation requirements (IR), actual yield (Y_a), irrigation water productivity (IWP), and gross production value (GPV). Results indicate that higher temperatures accelerate development and shorten the crop cycle. However, projected decreases in spring precipitation increase IR by 2–4% and reduce yields by 4–6% in future scenarios without adaptation, negatively affecting GPV. Early sowing with short-season varieties at moderate to high densities reduces IR by 29–34% but entails yield penalties of 53–55%; long-season varieties with high density increase Y_a by 3–13% when water is not limiting; and medium-season varieties with anticipated sowing, high density, and 90% irrigation efficiency increase IWP by 22–25%. Tailored AAMs balance water, productivity, and economic value, enhancing climate resilience in the Mediterranean. Full article

(This article belongs to the Special Issue Climate Change and Its Impact on Crop Production: Enhancing Resilience and Environmental Sustainability)

► Show Figures

Figure 1

33 pages, 10188 KB

Open AccessArticle

Regulatory Mechanisms Underlying Flavonoid-Mediated Restructuring of the Rhizosphere Microbiome in Alfalfa (Medicago sativa L.) Under Salt Stress

by Zuoliang Long, Fei Zhang, Shuhan Zhang, Shaowei Li, Xiaoli Wang, Xinqiang Zhu and Feifan Leng

Agronomy 2026, 16(19), 1871; https://doi.org/10.3390/agronomy16191871 - 22 Sep 2026

Abstract

This study employed two Medicago sativa L. varieties with contrasting salt tolerance—Zangmu No.1 (ZM1, salt-tolerant) and Zangmu No.2 (ZM2, salt-sensitive)—to investigate root exudate composition, rhizosphere microbiome assembly, and their potential correlations under 0 mM, 100 mM, and 200 mM NaCl stresses. Under 200 [...] Read more.

This study employed two Medicago sativa L. varieties with contrasting salt tolerance—Zangmu No.1 (ZM1, salt-tolerant) and Zangmu No.2 (ZM2, salt-sensitive)—to investigate root exudate composition, rhizosphere microbiome assembly, and their potential correlations under 0 mM, 100 mM, and 200 mM NaCl stresses. Under 200 mM NaCl, ZM1 exhibited specific activation of flavonoid-related metabolic pathways (including flavonoid degradation and tyrosine metabolism), resulting in significant upregulation of characteristic flavonoids such as naringin (a metabolite designated as NEG885 in our LC-MS library) and apigenin (POS148) in root exudates. Correlation analysis revealed that these metabolites were significantly and positively associated with the enrichment of salt-tolerant bacterial taxa, including Pseudarthrobacter and Adhaeribacter. In contrast, ZM2 under identical stress conditions showed significantly enhanced synthesis of p-hydroxyphenylacetic acid (NEG151, p < 0.05) which correlated with Limnobacter and Flavobacterium, indicating ZM2’s comparatively limited metabolic regulatory capacity. Notably, exogenous supplementation of salt-tolerant plant growth-promoting rhizobacteria (PGPR) from γ-Proteobacteria (Atlantibacter, Enterobacter) and Bacilli (Priestia) effectively alleviated growth inhibition in Medicago sativa (both ZM1 and ZM2) under 200 mM NaCl, primarily through promoting root/shoot elongation, leaf expansion, and photosynthetic efficiency while maintaining root “high K⁺/low Na⁺” ion homeostasis. These PGPR demonstrated multifunctional traits including indole-3-acetic acid biosynthesis, phosphate solubilization, and nitrogen fixation. qRT-PCR analysis confirmed their regulatory effects on salt-responsive genes such as CHI1 (chalcone isomerase 1) and CYP75A1 (flavonoid 3′,5′-hydroxylase), mediating root development and ion balance. This work elucidates the potential regulatory role of flavonoid metabolism in Medicago sativa’s recruitment of beneficial microbiota under salt stress, providing a theoretical foundation for developing salt-resistant cultivars through plant–microbe synergy strategies. Full article

(This article belongs to the Section Plant-Crop Biology and Biochemistry)

► Show Figures

Figure 1

16 pages, 1656 KB

Open AccessArticle

Growth and Physiological Responses of Brassica chinensis to Pristine and Fe/Mn-Modified Pteroceltis tatarinowii Biochar in Copper-Contaminated Soil

by Yong Hui, Yanwu Mo, Riqiang Tao and Youbao Wang

Agronomy 2026, 16(19), 1870; https://doi.org/10.3390/agronomy16191870 - 22 Sep 2026

Abstract

The ecological restoration of heavy metal-contaminated soil and the evaluation of its remediation efficacy have drawn considerable research interest. This 90-day pot experiment examined the effects of pristine and modified Pteroceltis tatarinowii biochars on Brassica chinensis grown in copper-contaminated soil; treatment-specific day-0 soil [...] Read more.

The ecological restoration of heavy metal-contaminated soil and the evaluation of its remediation efficacy have drawn considerable research interest. This 90-day pot experiment examined the effects of pristine and modified Pteroceltis tatarinowii biochars on Brassica chinensis grown in copper-contaminated soil; treatment-specific day-0 soil Cu concentrations ranged from 111.25 to 136.45 mg kg⁻¹. Pristine biochar (BC), FeCl₃-modified biochar (FBC), and KMnO₄-modified biochar (MBC) were applied at 1%, 3%, and 5% relative to soil mass, with three pots per treatment and an unamended control. Responses varied with the material, application rate, and measured endpoint. At 5% FBC, plant height and root length reached 12.47 and 14.13 cm, respectively, representing increases of 55.29% and 120.78% relative to the control. At this rate, FBC also produced significantly greater shoot fresh weight and root dry weight than every other treatment. Both 3% and 5% FBC increased shoot dry weight and reduced POD and SOD relative to the control; 3% FBC also reduced MDA. All amended treatments had lower mean shoot Cu concentrations than CK, but concentration and organ burden did not change in parallel. Treatment-mean estimates showed that shoot Cu burden decreased from approximately 0.50 μg plant⁻¹ in CK to 0.21–0.28 μg plant⁻¹ in the 5% treatments, whereas root Cu burden in 5FBC was approximately 0.092 μg plant⁻¹ compared with 0.065 μg plant⁻¹ in CK. Together, the growth and physiological responses identify FBC as a priority candidate for the further evaluation of P. tatarinowii branch biochar in mine-affected farmland. They do not establish a uniform ranking across physiological indicators, an intrinsic advantage of Fe over Mn modification, or alleviation of Cu toxicity independent of an uncontaminated-soil control. Full article

(This article belongs to the Section Soil and Plant Nutrition)

► Show Figures

Figure 1

18 pages, 3680 KB

Open AccessArticle

Microbial Network Complexity Emerges as a Key Predictor of Soil Multifunctionality Across Alfalfa Fields of Different Planting Years

by Zhibo Zhou, Mengke Zhang, Peng Xie and Yun Wang

Agronomy 2026, 16(19), 1869; https://doi.org/10.3390/agronomy16191869 - 22 Sep 2026

Abstract

Long-term alfalfa monoculture can lead to soil degradation, yet how microbial community attributes drive changes in soil multifunctionality (SMF) remains poorly understood. Here, we examined SMF and microbial community attributes across alfalfa fields over three planting year periods (3, 7, and 11 years) [...] Read more.

Long-term alfalfa monoculture can lead to soil degradation, yet how microbial community attributes drive changes in soil multifunctionality (SMF) remains poorly understood. Here, we examined SMF and microbial community attributes across alfalfa fields over three planting year periods (3, 7, and 11 years) and used hierarchical partitioning and partial least squares path modeling to identify the key predictors of SMF and their influence pathways. SMF declined progressively with increasing planting years, decreasing by 26.3% from the 3-year to the 11-year fields, accompanied by decreases in alpha diversity and network complexity. Hierarchical partitioning analysis identified fungal and bacterial network complexity as the two most important predictors. PLS-PM analysis further revealed that planting years were associated with soil properties, triggering distinct inferred pathways for bacteria and fungi. In bacterial communities, alpha diversity enhanced soil multifunctionality through both direct positive effects and an indirect pathway, wherein suppressing beta diversity led to increased network complexity. In fungal communities, alpha diversity directly benefited SMF but simultaneously suppressed beta diversity, which in turn reduced network complexity. These findings indicate that microbial network properties play a central role in mediating soil multifunctionality under continuous alfalfa cropping, providing a network-based perspective for evaluating soil health in agroecosystems. Full article

(This article belongs to the Section Soil and Plant Nutrition)

► Show Figures

Figure 1

17 pages, 308 KB

Open AccessReview

Dual-Edged Roles of Fungal Chlamydospores in Plant Protection: Research Progress and Application Potential

by Jie Mei, Huanran Liu, Ying Tian, Yudie Lv, Xiliang Jiang and Mei Li

Agronomy 2026, 16(19), 1868; https://doi.org/10.3390/agronomy16191868 - 22 Sep 2026

Abstract

Chlamydospores are thick-walled, dormant propagules formed by fungi in response to environmental stress. They play contrasting roles in plant protection: serving as persistent inocula of soil-borne pathogenic fungi that contribute to recurrent disease outbreaks, while also acting as highly stress-resistant propagules for fungal [...] Read more.

Chlamydospores are thick-walled, dormant propagules formed by fungi in response to environmental stress. They play contrasting roles in plant protection: serving as persistent inocula of soil-borne pathogenic fungi that contribute to recurrent disease outbreaks, while also acting as highly stress-resistant propagules for fungal biocontrol formulations. This review examines the ultrastructure, regulation of differentiation, soil survival, and germination behaviour of fungal chlamydospores. It compares diverse survival strategies among pathogenic fungi and discusses natural disease-suppressive mechanisms, including soil fungistasis and germination–lysis. Furthermore, this review highlights the field application advantages of chlamydospores from Trichoderma and nematophagous biocontrol fungi, together with functionally analogous microsclerotia from entomopathogenic fungi. Finally, we identify major challenges in understanding the molecular regulation of chlamydospores, standardizing formulations, and quantitatively characterizing their ecological dynamics in soil. Addressing these challenges will support the sustainable management of soil-borne diseases and the development of fungal biocontrol products. Full article

(This article belongs to the Special Issue Advances in Biological Control and Ecological Interactions in Agroecosystems)

22 pages, 5250 KB

Open AccessArticle

FromChamber to Orchard: Limited Efficacy of Exogenous Salicylic Acid in Field-Grown Sweet Cherry Across Three Seasons

by Francisco Maldonado, Cristian Ackerknecht-Espinosa, Yerko Moreno-Simunovic, Fernando Guerra and César Acevedo-Opazo

Agronomy 2026, 16(19), 1867; https://doi.org/10.3390/agronomy16191867 - 22 Sep 2026

Abstract

Salicylic acid (SA) is an endogenous phytohormone involved in stress signaling, yet its efficacy under commercial orchard conditions remains insufficiently tested. This multi-season study evaluated foliar SA (72.4 µM) on gas exchange, midday xylem water potential (Ψ_x), leaf temperature, water-use efficiency [...] Read more.

Salicylic acid (SA) is an endogenous phytohormone involved in stress signaling, yet its efficacy under commercial orchard conditions remains insufficiently tested. This multi-season study evaluated foliar SA (72.4 µM) on gas exchange, midday xylem water potential (Ψ_x), leaf temperature, water-use efficiency (WUE), and fruit quality in two sweet cherry cultivars (Prunus avium L. cv. Lapins and cv. Santina) across three consecutive seasons (2019/20–2021/22) in Pencahue, Maule Region, Chile. Generalized Linear Mixed Models applied to all 109 physiological date × variable comparisons, with joint correction for multiple testing (Benjamini–Hochberg FDR and Bonferroni), identified a single robust treatment effect: a less negative (higher) midday Ψ_x under SA in cv. Santina on 16 January 2021 (−0.65 vs. −0.80 MPa in Control; adjusted p = 0.020), i.e., a more favorable plant water status. No comparison involving net photosynthesis, stomatal conductance, leaf temperature, or WUE remained significant after correction, and fruit quality was unaffected in both cultivars. Principal Component Analysis separated a gas-exchange axis from a WUE axis, with the largest Control–SA centroid displacement in the same season as the confirmed Ψ_x effect. Because SA is expected to act as a stress-conditioned elicitor—that is, to be effective mainly under high atmospheric demand (VPD) or a pronounced water deficit—the season in which the single confirmed effect appeared constitutes a direct test of that expectation. Contrary to this, the effect occurred in the mildest rather than in the most demanding season, arguing against a simple high-VPD timing rule and supporting cultivar- and season-specific rather than universal expectations for SA in orchard water management. These conclusions apply to the single concentration tested (72.4 µM) under fully irrigated commercial management in one orchard and should not be extrapolated to higher application rates or to water-limited conditions. Full article

(This article belongs to the Section Horticultural and Floricultural Crops)

► Show Figures

Figure 1

26 pages, 2805 KB

Open AccessArticle

Integrated Fertilization Improves Tomato Productivity, Fruit Quality, and Soil Properties

by Marco Piñón-Balderrama, Adriana Hernández-Rodríguez, Linda Noperi-Mosqueda, Mariana Vargas-Beltrán, Claudia Piñón-Balderrama, Dámaris Ojeda-Barrios, Francisco Piña-Ramírez and Aztrid Estrada-Beltrán

Agronomy 2026, 16(19), 1866; https://doi.org/10.3390/agronomy16191866 - 22 Sep 2026

Abstract

Intensive horticultural production relies heavily on mineral fertilizers, which may negatively affect soil quality and long-term sustainability. Integrated fertilization represents an alternative for reducing these risks; however, its effects on the soil–plant–fruit system remain incompletely understood. The objective of this study was to [...] Read more.

Intensive horticultural production relies heavily on mineral fertilizers, which may negatively affect soil quality and long-term sustainability. Integrated fertilization represents an alternative for reducing these risks; however, its effects on the soil–plant–fruit system remain incompletely understood. The objective of this study was to evaluate the effects of different integrated fertilization strategies, based on the combination of organic amendments and reduced chemical fertilization, on soil properties, tomato productivity, and fruit nutritional quality. Ten treatments with five replicates were evaluated under a completely randomized design in plants grown under a high-tunnel system. The results showed that integrated fertilization enabled a 40–50% reduction in macronutrient inputs and the complete elimination of micronutrient fertilization, while achieving yields that did not differ significantly from those of the chemical control and were 480–520% higher than those of the unfertilized control. In addition, integrated fertilization increased fruit concentrations of calcium, magnesium, phenolic compounds, and lycopene. Treatments incorporating organic amendments produced with the incorporation of Trichoderma sp. showed higher potassium concentrations in the fruit. Soil organic matter increased by 80–250%. These results indicate that integrated fertilization can reduce the use of mineral fertilizers while maintaining crop productivity and improving both soil quality and the nutritional and functional quality of the fruit. Full article

(This article belongs to the Section Soil and Plant Nutrition)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Agronomy, Volume 16, Issue 19 (October-1 2026) – 16 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI