Search Results (266)

Excessive planting density and heavy rainfall weather threatens global agriculture, particularly affecting maize. Biochar is an environmentally friendly soil amendment that has a yield-increasing effect. However, the regulatory mechanism of biochar frequency on crop internode development and photosystem II photosynthetic efficiency remains unknown. A total of nine treatments were followed in this experiment. Three applications of biochar were as follows: no biochar application (B0); biochar application at 4.2 t ha⁻¹ year⁻¹ (B1); and biochar application at 8.4 t ha⁻¹ 2 year⁻¹ (B2), alongside three nitrogen (N) fertilizer rates (0, N0; 180 kg ha⁻¹, N1 and 225 kg ha⁻¹, N2). The results showed that the internode thickness of the 2nd to 5th nodes under N2B2 treatment increased by 17.7%, 16.0%, 19.7%, and 21.7%, respectively, compared to N0B0. Annual biochar application had a higher stem diameter coefficient for the 1st to 3rd nodes than no biochar (B0) and treatments applied every two years (B2). Annual biochar application had the highest dry weight of internodes and plant height compared with B0 and B2. The relative chlorophyll content of leaves was significantly increased by biochar combined with N fertilizer or by N fertilizer alone. Biochar combined with N fertilizer significantly reduced NPQt and ΦNPQ, which were reduced by 59% and 50%, respectively, under N2B1 treatment compared with N0B0. The N2B1 treatment increased ΦII by 30% compared to N0B0. Stem diameter coefficient was significantly negatively correlated with NPQt and ΦNPQ and significantly positively correlated with ΦII and Fv/Fm. Compared to B1, B2 increased the maize yield. Annual biochar application combined with N fertilizer reduced stem collapse and enhanced post-flowering photosynthesis. Overall, considering the yield traits, 8.4 t ha⁻¹ biochar application combined with 180 kg ha⁻¹ N fertilizer treatment was the best. This study will provide reference data for cultivation regulation to enhance maize’s resistance to collapse and maintain photosynthetic capacity. Full article

Potentially toxic element (PTE) co-contamination in farmland severely threatens global food safety. To identify effective remediation strategies, large-scale field trials were conducted in two karst regions of Southwest China highly co-contaminated with Cd, Pb, As, Cr, and Hg. The efficacy of seven commercial soil amendments (biochar (BC), fused calcium–magnesium phosphate (FCMP), humic acid (HA), potassium humate (KH), oyster shell powder (OS), composite passivator (PA), and quicklime (QL)) on soil physicochemical properties, PTE bioavailability, maize (Zea mays L.) yield, and plant tissue distribution was systematically evaluated. The results indicated that organic amendments, specifically BC, HA, and KH, consistently outperformed inorganic treatments. These organic materials significantly decreased the diethylenetriaminepentaacetic acid (DTPA)-extractable fractions of cationic PTEs (e.g., Cd and Pb decreased by up to 39.5% under KH treatment) without inadvertently mobilizing As, unlike the alkaline inorganic amendments. This reduction in soil bioavailability closely correlated with improved plant performance, leading to maximum increases in root biomass (up to 130% with BC) and grain yield (up to 27.6% with HA). Furthermore, BC and humic substances effectively restricted PTE accumulation in grains (Cd and Pb reduced by up to 42.1%). Tissue distribution analysis revealed a consistently low root-to-stem translocation factor (TF < 0.2), indicating that roots acted as the primary sink for absorbed PTEs. This study indicates that commercial organic amendments support the use of a superior, broad-spectrum strategy for mitigating multi-PTE risks and ensuring safe agricultural utilization in severely co-contaminated areas. Full article

With the advancement of agricultural modernization, issues related to resource conservation, intensive utilization, and green, low-carbon development have become increasingly prominent. To enhance water and fertilizer use efficiency in Henan Province and promote green, low-carbon, and sustainable agricultural development, field experiments were conducted during 2023–2024. The experiment employed a randomized complete block design with three replications. Each plot measured 30 m² (5 m × 6 m), totaling 36 plots. An IoT-based real-time coordinated water-fertilizer regulation technology, driven by continuous WSH-TDR310S sensor monitoring of soil moisture and nitrogen status with automated threshold-based control logic, was implemented. By transforming the traditional static scheduling approach into a dynamic feedback mechanism driven by real-time sensor data, the synchronization between resource supply and crop demand was achieved. This study aimed to elucidate the response characteristics of summer maize growth dynamics and farmland N₂O emissions under the proposed regulation strategy. The experiment included three levels of water deficit (mild, moderate, and severe) and three fertilization levels (low, medium, and high), resulting in a total of nine real-time water–fertilizer coordinated regulation treatments, along with three local border irrigation control treatments. The results showed that under real-time water–fertilizer regulation, plant height, stem diameter, and leaf area index of summer maize exhibited unimodal variation patterns, with the medium irrigation–medium fertilization (B2) treatment performing optimally. Compared with the border-irrigation medium-fertilization control (D2), plant height and stem diameter under the B2 treatment increased significantly. Cumulative farmland N₂O emissions increased with higher irrigation and fertilization levels, with the border-irrigation high-fertilization treatment producing the highest emissions. Yield formation was mainly governed by structural growth traits, with plant height showing the strongest predictive ability, followed by stem diameter, whereas leaf area index showed weaker explanatory power. Summer maize yield exhibited a unimodal response to both irrigation and nitrogen input levels. Compared with the D2 treatment, the B2 treatment increased grain yield by 41.33%, while achieving water-saving and fertilizer-saving rates of 38.10% and 35.75%, respectively, thereby achieving an optimal balance between high yield and efficient water–fertilizer utilization. These findings provide theoretical support for summer maize production in the North China Plain and contribute to the promotion of green and sustainable agricultural development. Full article

Polygonatum cyrtonema Hua (PCH) is traditionally recognized as both an edible and medicinal food source. Its rhizomes contain numerous bioactive compounds, notably polysaccharides and flavonoids, which serve as key constituents in functional food development. However, the cultivation of PCH is often hindered by allelopathic effects, which diminish its quality and restrict its industrial application. To mitigate these allelopathic influences, three types of biochars derived from maize straw (MB), rice husk (RB), and tea stem (TB) were applied at concentrations of 0%, 2%, and 4%. Initially, the physicochemical properties of these biochars were characterized, followed by an evaluation of their impact on (1) the synthesis of quality-related components, secondary metabolites, and allelochemicals within PCH rhizomes and (2) the fundamental physicochemical properties and bacterial community structure of the PCH rhizosphere soil. The findings indicated that the application of 4% RB significantly enhanced the content of total polysaccharides by 48.5%, total flavonoids by 30.2%, total saponins by 28.6%, and total polyphenols by 18.3%, while concurrently reducing protein (PRO) and free amino acid (FAA) concentrations in the rhizomes. Non-targeted metabolomic analyses revealed that biochar amendments (1) upregulated metabolites involved in the citrate cycle and galactose metabolism pathways, thereby facilitating energy supply and precursors for polysaccharide biosynthesis; (2) downregulated metabolites involved in the arginine biosynthesis pathway, which is unfavorable for protein and amino acid synthesis; (3) decreased the abundance of six identified allelochemicals, including 5-hydroxy-L-tryptophan and andrographolide, with the most pronounced effect observed in the 4% TB treatment (T2); (4) improved soil physicochemical parameters such as pH, soil organic matter (SOM), total nitrogen (TN), and available potassium (AK); and (5) altered the rhizosphere bacterial community by enriching beneficial phyla, notably Myxococcota and Gemmatimonadota. These modifications in soil properties and bacterial community composition were closely associated with enhanced rhizome quality and a reduction in allelochemical accumulation. Collectively, the results of this study elucidate the potential mechanisms linking biochar application to allelopathy mitigation, optimization of soil microbial communities, and improvement of PCH rhizome quality. This research provides a theoretical basis for the production of high-quality PCH while concurrently minimizing allelochemical accumulation in its rhizomes. Full article

Modifying food systems is required when they are threatened by a changing climate. Oil palm (OP) is a very important crop and climate change (CC) may decrease the areas in which OP can grow, as indicated by CLIMEX modelling. OP is affected by basal stem rot (BSR) and increasing incidences are indicated. Palm oil is used in many foods and biodiesel; Indonesia and Malaysia produce the largest volumes of the commodity. CLIMEX modelling of future suitable climates have also been applied to soybean, maize and the common bean (CB). The data for these crops were compared to those for OP in Indonesia, Malaysia and Thailand in the current paper to determine if growing the crops in the same regions in which OP is grown is possible in the future. Soybean had higher areas of suitable climate compared to OP. BSR and OP mortality further disadvantaged OP. The suitable climate for OP decreased significantly in Thailand by 2050 and in areas of Indonesia and Malaysia by 2070; the equivalent areas for soybean remained at high suitability. OP climate suitability further declined by 2100 in these and some other regions. Soybean could usefully be grown to diversify from the OP monoculture in many cases. Maize could be a possible alternative infrequently and the CB does not appear to be a viable alternative. These comparisons are unique and the methods could be employed in other systems. Full article

Stalk lodging (the structural failure of plant stems prior to harvest) remains a major constraint to global cereal crop production, reducing yields, impairing grain quality, and increasing harvest losses. Since cellulose microfibrils are the primary load-bearing components in plant cell walls, the microfibril angle is widely considered a critical determinant of stalk mechanical properties. X-ray diffraction is a common technique for microfibril angle measurement, yet its applicability to cereal crops has not been fully validated. This study assessed the utility of X-ray diffraction based microfibril angle measurements for maize (Zea mays) and sorghum (Sorghum bicolor) stalks using the T-parameter method. Rind tissue samples from multiple maize and sorghum genotypes were analyzed using two diffractometers with copper (Cu) and molybdenum (Mo) X-ray sources. Corresponding internodes were also evaluated for rind penetration resistance, material bending stiffness, and bending strength to test whether measured microfibril angles reflected biologically meaningful variation. Across all genotypes and internodes, including preliminary observations from phenotypic extremes in select groups, microfibril angle values were highly uniform, with maize averaging 24.6° (Cu) and 29.1° (Mo) and sorghum averaging 24.3° (Cu) and 29.4° (Mo). microfibril angles exhibited extremely low variability (coefficient of variation < 3.3%), in stark contrast to the much higher variability observed in mechanical properties (CV = 20.5–47.1%). Systematic differences of ~20% between Cu- and Mo-based measurements were consistent across sample groups. Correlations between microfibril angle and mechanical properties were weak or absent; only Cu-derived microfibril angle showed a marginal relationship with bending stiffness, while Mo-derived microfibril angle showed no significant correlations. Pooled analyses further confirmed that microfibril angle remained nearly constant despite a wide range of mechanical property values. Collectively, these findings demonstrate that X-ray diffraction based microfibril angle measurements using the T-parameter method have limited applicability to cereal stalk tissues, as the method failed to capture biologically relevant variation. The uniformity of measured angles, lack of correlation with mechanical properties, and dependence on X-ray source raise concerns about the suitability of this method for maize and sorghum. These results highlight the need for refined or alternative microfibril angle measurement techniques to better understand the role of cellulose microfibril orientation in stalk lodging resistance. Full article

Soil salinization represents a significant abiotic constraint to global agricultural sustainability. The potential of extremophile plant growth-promoting bacteria (PGPB) to alleviate such stress in maize was investigated in this study. Siderophore-producing PGPB enhance plant growth and improve the rhizosphere microenvironment by increasing nutrient availability and inducing systemic resistance. Two salt-tolerant, high-siderophore-producing PGPB strains, Bacillus toyonensis TRM58010 and Peribacillus frigoritolerans TRM58009, were isolated and identified from soil samples collected on the Pamir Plateau. In this study, we found that B. toyonensis TRM58010 synthesized catechol-type siderophores, which enhanced iron availability for maize in saline–alkaline conditions, thereby improving iron nutrition and directly promoting root and stem growth under salt stress. P. frigoritolerans TRM58009 produced hydroxamate-type siderophores, which increased maize iron uptake and stimulated antioxidant enzyme activity, mitigating oxidative stress caused by salinity and alkalinity and supporting overall plant health. Both strains demonstrated robust tolerance to extreme alkaline and saline conditions. Hydroponic and pot experiments showed that these strains significantly improved maize germination rate, root and stem development, plant height, leaf growth, antioxidant enzyme activities, and chlorophyll content under saline–alkaline stress. Notably, the application of P. frigoritolerans TRM58009 bacterial suspension increased maize leaf catalase, peroxidase, and superoxide dismutase activities by 15.712%, 11.584%, and 2.820%, respectively (all p < 0.05), while decreasing malondialdehyde (MDA) content by 15.685% (p < 0.05). P. frigoritolerans TRM58009 elevated chlorophyll a content by 23.4% (p < 0.05). These findings demonstrate the potential of extremophile PGPB strains to mitigate the impact of saline–alkaline stress on maize growth. The distinct growth-promoting effects of these strains, isolated from Pamir Plateau meadow soils, present a promising strategy for bioremediation of saline–alkaline lands and the development of efficient microbial fertilizers. By advancing the use of salt-tolerant siderophore-producing bacteria, this study lays the foundation for innovative approaches to enhance crop resilience and productivity in challenging environments. Full article

Soil salinization, as a key constraint to global agricultural sustainable development, has threatened over one billion hectares of farmland, posing severe challenges to staple crop production. Therefore, this review summarizes important advances in the molecular mechanisms of salt–alkali tolerance from the model plant Arabidopsis thaliana to staple crops (rice, maize, and wheat) and compares the commonalities and differences in physiological structure and molecular regulatory networks among these species. Studies have shown that plants respond to saline–alkali stress mainly through conserved mechanisms, including salt overly sensitive (SOS) signaling pathway-mediated ion homeostasis, accumulation of osmoprotectants, reactive oxygen species (ROS) scavenging, and coordination of multiple hormone signals. However, different species have evolved unique adaptive strategies: Arabidopsis has revealed core regulatory pathways, but its simple root system limits direct application in crops; rice employs root barriers and a stem node “ion filter” to precisely regulate Na⁺ transport; maize utilizes the C4 photosynthetic pathway along with efficient osmotic adjustment and tissue compartmentalization to enhance tolerance; and wheat achieves ion detoxification through TaHKT allele variation and vacuolar sequestration. Looking forward, future breeding for salt–alkali tolerance should adopt a “crop-centric” approach, focusing on the mining and molecular design of superior alleles, combined with gene editing and multi-trait integration, to provide a theoretical basis and strategic support for developing high-yield and stable crop varieties adapted to saline–alkali lands. Full article

Analyzing three-dimensional (3D) phenotypic parameters of maize seedlings is of significant importance for maize cultivation and selection. However, existing methods often struggle to balance cost, efficiency, and accuracy, particularly when capturing the complex morphology of seedlings characterized by slender stems. To address these issues, this study proposes a novel end-to-end automated framework for extracting phenotypes using only consumer-grade RGB cameras. The pipeline initiates with Instant-NGP to rapidly reconstruct dense point clouds, establishing the 3D data foundation for phenotypic extraction. Subsequently, we formulate a directed topological graph-based mechanism. By mathematically defining bifurcation constraints via vector analysis, this mechanism guides a depth-first traversal strategy to explicitly disentangle stem and leaf skeletons. Building upon these decoupled skeletons, organ-level point cloud segmentation is achieved through constraint-based expansion, followed by density-based spatial clustering (DBSCAN) to detect individual leaves. Algorithms combining point cloud geometry with 3D Euclidean distance are also implemented to calculate key phenotypes including plant height and stem width. Finally, single-leaf skeleton fitting is used to estimate leaf length, and principal component analysis (PCA) is adopted to determine the stem–leaf angle, realizing the comprehensive automatic extraction of maize seedling phenotypes. Experiments show that the proposed method achieves high accuracy in extracting key phenotypic parameters. The mean relative errors for plant height, stem width, leaf length, stem-leaf angle, and leaf area are 0.76%, 2.93%, 1.26%, 2.13%, and 3.33%, respectively. Compared with existing methods as far as we know, the proposed method significantly improves extraction efficiency by reducing the processing time per plant to within 5 min while maintaining such high accuracy. Full article

While increasing planting density is a viable strategy for enhancing maize yield, it concurrently elevates the risks of lodging and accelerated leaf senescence due to intensified inter-plant competition, which can ultimately compromise yield stability. A field experiment was conducted in Heilongjiang Province and the study investigated two maize cultivars, JNK728 (Jingnongke 728) and SD5 (Saide 5), under high-density planting conditions (90,000 plants ha⁻¹). The treatments were arranged in a factorial design, incorporating four nitrogen levels (0, 120, 240, and 360 kg N ha⁻¹) in combination with the presence or absence of a chemical regulator (30% diethyl aminoethyl hexanoate · ethephon), with water serving as the control. Results demonstrated that the integration of 240 kg N ha⁻¹ with chemical regulation significantly enhanced photosynthetic capacity—elevating chlorophyll content (SPAD), net photosynthetic rate (Pn), and activities of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCase) and phosphoenolpyruvate carboxylase (PEPCase)—while improving canopy structure through increased leaf area index (LAI) and optimized light distribution. This strategy also reinforced lodging resistance by optimizing plant morphology (reducing plant height and center of gravity), strengthening basal internodes (increasing stem diameter, dry weight per unit length, and mechanical strength), and promoting accumulation of stem structural components (cellulose, hemicellulose, lignin). Additionally, it facilitated post-anthesis nitrogen translocation to grains and up-regulated key nitrogen metabolism enzymes (glutamate synthetase-GS, glutamate dehydrogenase-GDH, and glutamate-pyruvate transaminase-GPT), thereby boosting nitrogen use efficiency. In contrast, excessive nitrogen (360 kg N ha⁻¹) suppressed these benefits and increased lodging. Consequently, the combined application of 240 kg N ha⁻¹ with chemical regulation achieved the highest yield, proving an effective approach for synergistically enhancing photosynthesis, lodging resistance, and nitrogen utilization in high-density maize systems. Full article

The use of biosolids in agriculture enhances soil fertility and organic matter, yet concerns remain over the accumulation of contaminants of emerging concern in soils and food crops. Despite increased land application, long-term field-based evidence on the environmental fate and plant uptake of these compounds is limited. This study hypothesized that prolonged biosolid application improves soil carbon and nitrogen without promoting triclosan (TCS) or sulfamethoxazole (SMX) persistence or uptake under rainfed and rainfed + irrigation maize systems. Over a decade and half, a field trial was conducted with biosolids applied at rates of 0, 4, 8, and 16 t ha⁻¹ yr⁻¹. Soil samples were analyzed for organic carbon, total nitrogen, pH, electrical conductivity, TCS, and SMX. Maize stem, leaves, and grain were similarly analyzed for TCS and SMX. Results showed that biosolids significantly improved soil organic carbon and nitrogen (p ≤ 0.0001), but also increased soil acidification and salinity. SMX was not detected in either soil or plant tissues at any rate. Although TCS was absent in soils six months post-application, it was detected in maize shoots and grains at 8 and 16 t ha⁻¹ yr⁻¹, highest in stems (6.66–8.92 ng g⁻¹) and lowest in grains (3.25–4.28 ng g⁻¹). Estimated dietary intake was well below health risk thresholds. These findings support biosolid application ≤ 16 t ha⁻¹ yr⁻¹ as a safe and effective treatment for improving soil fertility in maize systems. Future research should explore transformation products, microplastics, and cumulative exposure under varied agroecosystems. Full article

Soil salinization is a major threat to agricultural sustainability. Poly-gamma-glutamic acid (γ-PGA), a biopolymer produced by microbial fermentation, has received attention as a biostimulant due to its positive effects on crop performance. However, the function of γ-PGA in crop salt stress tolerance and its effect on the rhizosphere are unclear. This study explores the effects of γ-PGA application on rhizosphere soil nutrients and the soil–physical environment and examines the salt tolerance response of maize seedlings grown in saline–alkali soil under such an application regime. The results show a significant promotion of maize seedling growth and of nutrient accumulation with γ-PGA application under salt stress; plant dry weight, stem diameter, and plant height increased 121%, 39.5%, 18.4%, respectively, and shoot accumulation of nitrogen, phosphorus, potassium, and carbon increased by 1.38, 2.11, 1.50, and 1.36 times, respectively, under an optimal-concentration γ-PGA treatment (5.34 mg kg⁻¹ (12 kg ha⁻¹)) compared with the control. γ-PGA treatment significantly decreased rhizospheric pH and soil electrical conductivity and significantly increased nutrient availability in the rhizosphere, especially available nitrogen (AN) and available potassium (AK). Compared with the control, AN, available phosphorus (AP), and AK increased by 13.9%, 7.70%, and 17.7%, respectively, under an optimal concentration treatment with γ-PGA. γ-PGA application also significantly increased the activities of urease, acid phosphatase, alkaline phosphatase, dehydrogenase, and cellulose in rhizosphere soil by 35.5–39.3%, 35.4–39.3%, 5.59–8.85%, 18.9–19.8%, and 19.2–47.0%, respectively. γ-PGA application significantly decreased Na⁺ concentration and increased K⁺ concentration in shoots, resulting in a lowering of the Na⁺/K⁺ ratio by 30.5% and an increase in soluble sugar and soluble protein contents. Therefore, rhizosphere application of water-soluble and biodegradable γ-PGA facilitates the creation of an optimized rhizospheric environment for maize seedling and overcomes osmotic and ionic stresses, offering possibilities for future use in drip-irrigation systems in the cultivation of crops on saline-alkali land. Full article

A complex of Fusarium species frequently infects maize, causing root, ear, and stem rot, yield losses, reduced seed quality, and mycotoxin accumulation. To quantify Fusarium species composition and mycotoxin contamination, we conducted a first nationwide monitoring in Swiss commercial grain maize over three years (2008–2010), followed by grain maize hybrid experiments across five sites (2011–2013). Samples were analysed for species incidence, fungal DNA, and the mycotoxins deoxynivalenol, zearalenone, and fumonisins. For each field, crop management data were collected. Fusarium graminearum, F. verticillioides, F. subglutinans, and F. proliferatum were predominant, and deoxynivalenol was the most frequent toxin, with 55% of the samples exceeding the European pig feed guidance value (0.9 mg kg⁻¹). Overall, fumonisin contamination was low: only 11% of samples were above the limit of detection. The year, the length of the growing period, and the timing of the harvest were the principal determinants of F. graminearum infection and deoxynivalenol/zearalenone accumulation, whereas other agronomic factors, including crop rotation, soil management, and maturity class, showed only limited or inconsistent effects. Results from this study provide evidence that farmers should avoid long growing periods and late harvests to reduce the risk of high deoxynivalenol/zearalenone content. The maize hybrid experiments confirmed the overriding influence of weather conditions on Fusarium species incidence and mycotoxin content, leading to high inter-annual variability. These results highlight the need for standardised, long-term field experiments to disentangle agronomic effects and environmental drivers. Full article

Soils with an albic horizon (characterized by a bleached, nutrient-poor eluvial layer), classified primarily as Albic Planosols and associated groups (e.g., Albic Luvisols and Retisols) in the World Reference Base for Soil Resources (WRB), are widespread in Northeast China and suffer from inherent poor nutrient availability and low crop productivity. The present study aimed to evaluate the efficacy of novel microbial–enzyme composite biofertilizers in ameliorating Albic soils. This comprehensive assessment investigated their effects on soil nutrient availability, microbial community structure, and the activities of key enzymes involved in nutrient cycling (e.g., dehydrogenase and phosphatase). Concurrently, the impact on maize crop performance was determined by measuring changes in agronomic traits, including chlorophyll content, stem diameter, and final grain yield. A field experiment was conducted in Heilongjiang Province during the 2023 maize growing season using a randomized block design with six treatments: CF (conventional chemical fertilizer, 330 kg·ha⁻¹ NPK), OF (chemical fertilizer + 1500 kg·ha⁻¹ organic carrier), BF1 (OF + 75 kg·ha⁻¹ marine actinomycetes), BF2 (OF + 75 kg·ha⁻¹ actinomycetes + 45 kg·ha⁻¹ phytase), BF3 (OF + 75 kg·ha⁻¹ actinomycetes + 45 kg·ha⁻¹ mycorrhizal fungi + 45 kg·ha⁻¹ phytase), and BF4 (OF + 75 kg·ha⁻¹ actinomycetes + 45 kg·ha⁻¹ mycorrhizal fungi + 45 kg·ha⁻¹ phytase + 45 kg·ha⁻¹ β–glucosidase). The results showed that biofertilizers significantly increased microbial abundance and enzyme activity. The integrated treatment BF4 notably enhanced topsoil fungal abundance by 188.1% and dehydrogenase activity in the 0–20 cm layer, while also increasing available phosphorus by 92.6% at maturity. Although BF4 improved soil properties the most, BF3 produced the highest maize yield—boosting grain output by 18.3% over CF—and improved stem diameter and chlorophyll content. Strong correlations between microbial parameters and enzyme activities indicated a nutrient-cycling mechanism driven by microorganisms, with topsoil fungal abundance positively linked to alkaline phosphatase activity (r = 0.72) and subsoil bacterial abundance associated with available phosphorus (r = 0.65), demonstrating microbial–mediated carbon–phosphorus coupling. In conclusion, microbial–enzyme biofertilizers, particularly BF4, provide a sustainable strategy for enhancing Albic soil fertility and crop productivity. Full article

Aiming at the reliability of ear picking and the consistency of stalk chopping length in the process of corn ear and stalk harvesting, a new type of corn harvester with both ear and stalk harvesting based on exciting ear picking was developed. Based on the vertical cutting table, the machine realizes the excitation of the ear during the process of stalk transportation by rotating the eight-edged special-shaped pick-up roll, and the stable and orderly transportation of stalks before cutting is realized by the way of clamping and conveying with the rear rollers. By analyzing the configuration and parameter determination methods of the main working parts, the high-efficiency and low-loss harvest of the ear was realized, and the consistency of the cut length of the stalk was guaranteed. A discrete element model (DEM) of ear-bearing maize plants was established using EDEM (version 2024, Altair Engineering, Troy, MI, USA) simulation software, and a five-factor, three-level quadratic orthogonal rotation experiment was conducted based on Response Surface Methodology (RSM). The simulation results indicated that the optimal operational quality was achieved under the following parameters: a header angle of 10°, a snapping roller speed of 942 rpm, a clamping roller speed of 215 rpm, and a moving blade speed of 1450 rpm. Furthermore, multiple sets of field trials were conducted at various forward speeds to validate these findings. The mean values of seed loss rate, ear loss rate, and seed breakage rate are 0.51%, 0.55%, and 0.32%, respectively, for the harvester at operating speeds of 4 km/h, 6 km/h, 8 km/h, and 10 km/h. The σ values are 97%, 98%, 97%, and 98%. The field harvesting performance indexes meet the requirements of technical specifications for evaluating the operation quality of corn combine harvester, and meet the design requirements of low loss, high efficiency, and consistency of stem chopping length. Full article