The use of biochar and lime (CaO) is a common approach to mitigating soil acidification. However, little is known about how biochar and lime amendments impact N₂O emissions and potential microbial mechanisms. We conducted a 45-day microcosm incubation experiment to examine N₂O emission and associated functional guilds to biochar and lime amendment in an acidic tea plantation soil. Results show that lime and biochar treatments significantly reduced cumulative N₂O emissions by 49.69% and 63.01%, respectively, while significantly increasing cumulative CO₂ emissions by 27.51% and 19.35%, respectively. Additionally, lime and biochar treatments significantly decreased the abundances of bacterial nirK, nirS, nosZ and fungal nirK genes, while increasing that of the ammonia-oxidizing bacteria (AOB) and the complete ammonia-oxidizing bacteria (comammox) amoA genes. The stimulated or inhibitory effects of biochar on functional genes abundances were higher than lime. The N₂O emission rate was positively linked with the abundance of the fungal nirK gene but was negatively correlated with AOB and comammox amoA genes abundances. The random forest and linear regression analysis revealed that fungal denitrifiers were the most important predictors of N₂O emissions. Lime and biochar amendments reduced the alpha diversity and altered the community composition of nirK-harboring fungal denitrifiers. Ascomycota was the dominant fungal denitrifiers belonging to the families Nectriaceae, Aspergillaceae, and Chaetomiaceae, and the relative abundances of genera Chaetomium, Penicillium and Fusarium were positively correlated with N₂O emissions. Overall, our findings suggest that biochar is more effective than lime in reducing N₂O emissions, and this is likely due to the powerful effects it has on community traits of nirK-harboring fungal denitrifiers.

As a crucial staple crop in agricultural production, maize is extensively cultivated worldwide and plays a pivotal role in ensuring global food security. However, the significant deficiency of essential amino acids (EAA) and conditionally essential amino acids (CEAA), such as lysine (Lys), tryptophan (Trp), methionine (Met), and cysteine (Cys), leads to an imbalance of amino acids in the grain. This study investigates the regulatory mechanism of sulfur (S) application for regulating the amino acid balance of maize grains. The results demonstrate that S application has substantial effects on both the maize yield and nutritional quality. The S application resulted in an increase in maize yield by simultaneously enhancing the grain number per ear (GN) and 100-grain weight (GW), while S application elevated protein concentration through the augmentation of Cys concentration in maize grains. Furthermore, the Cys in grains optimizes the amino acid balance by regulating the ratio of other amino acids, thereby enhancing the nutritional quality of maize while ensuring a steady increase in protein concentration, simultaneously. Overall, the S application at 60–90 kg ha⁻¹ synergistically improved both the yield and nutritional quality of maize, meeting the requirements for sustainable development in maize production. The findings offer a novel theoretical foundation and nutrient management approach for achieving high-yield and superior-quality maize production.

Sulfur (S) deficiency is increasingly recognized as a limiting factor for maize productivity, yet the physiological mechanisms underlying sulfur-driven yie

Simultaneous achievement of high yield and excellent quality in rice is essential for food security and human health. The coordinated application of nitrogen (N) and sulfur (S) can effectively increase the grain yield (GY) and grain protein concentration (GPC) of rice. A two-season field experiment was conducted to investigate the synergistic effects of combined N and S application on the GY and GPC of rice. This study employed four N rates (0, 120, 180, and 240 kg ha⁻¹, designated as N0, N1, N2, and N3, respectively) and four S rates (0, 30, 45, and 60 kg ha⁻¹, designated as S0, S1, S2, and S3, respectively) using two rice cultivars: Jiujiuxiang (JJX) and Jiuxiangyou (JXY). The experimental results demonstrate that N and S exert significant effects on the GY and GPC of rice, with notable interactive effects between these two nutrient elements. The synergistic fertilization of N and S enhanced the GY by improving rice plant photosynthesis and dry matter accumulation while increasing GPC through elevated cysteine concentration in grains. Compared to the unfertilized treatment, the GY of the JJX cultivar showed increases of 68.3–143.2% (Season I) and 59.4–133.4% (Season II) under combined N and S applications, while the GY of the JXY cultivar increased by 53.2–144.1% (Season I) and 66.0–192.9% (Season II). Similarly, the GPC of the JJX cultivar showed increases of 7.5–43.4% (Season I) and 5.7–43.9% (Season II) under combined N and S applications, while the GPC of the JXY cultivar increased by 13.1–66.7% (Season I) and 13.3–61.0% (Season II). Overall, whether on the JJX or JXY cultivars, the application of 180 kg ha⁻¹ of N combined with 45 kg ha⁻¹ of S (i.e., the N2S2 treatment) synergistically enhances GY and GPC in rice. The synergistic fertilization of N and S synergistically enhances both rice yield and nutritional quality by regulating plant growth dynamics, which meet the requirements for healthy and sustainable development in rice production systems.

N-(n-Butyl) thiophosphoric triamide (NBPT) degrades gradually when directly blended with compound fertilizer, which severely limits the product's shelf life. To address this limitation, a biodegradable coating layer composed of ethyl cellulose and stearic acid was applied to the surface of compound fertilizer granules via the solvent evaporation method, using industrially recyclable toluene and isopropanol as solvents. This approach enabled the stable integration of NBPT into compound fertilizers while maintaining its bioactivity. Incubation experiments demonstrated that the degradation rate of NBPT in the slow-release system compound fertilizer (SRS-CF) was reduced to 15.51% after 60 days of storage at 10°C, with a half-life of 221 days, in comparison with 17.9 days for directly adding NBPT to compound fertilizer. This study effectively addresses the technical bottleneck of the unstable incorporation of NBPT in compound fertilizers and provides feasible strategies for its practical application in compound fertilizer systems.

Introduction: Sulfur (S) deficiency has re-emerged as a constraint to maize production due to reduced atmospheric deposition and the widespread use of S-free fertilizers. However, how S fertilization influences yield formation under contrasting soil conditions in Northeast China remains insufficiently quantified. Methods: Here, a two-year field experiment was conducted on six representative soil types using five S rates (0, 30, 60, 90, and 120 kg S ha ^- ¹) with measurements of grain yield and its components, S and N accumulation and stoichiometry, and dry matter production and remobilization before and after silking. Results: Across the six soils, fitted optimal S rates (61.4–89.7 kg S ha ^- ¹) increased grain yield by 2.5%-25.8%, with the largest responses observed in black soil and aeolian sandy soil. Yield gains were mainly associated with increases in kernel number and thousand-kernel weight, supported by path analysis. Moderate S supply (S60–S90) enhanced S and N uptake at silking and maturity, improved N/S ratios, and increased pre-silking biomass accumulation. Biomass remobilization efficiency increased from 5.0% (S0) to 11.6%–11.7% (S60–S90), contributing to a higher harvest index (40.8% at S0 vs. 42.6%–42.7% at S30–S90). Pre-silking biomass was positively related to grain yield across soils. Discussion: Overall, under the studied conditions, S fertilization improved maize yield primarily through promoting early-season growth, nutrient coordination, and biomass remobilization rather than increasing post-silking assimilation alone. These findings provide a scientific basis for soil-specific sulfur management in temperate spring maize systems of Northeast China.