ACS agricultural science & technology最新文献

Pesticides can lose effectiveness and harm the environment due to factors like their chemical properties, weather conditions, and how they are applied. This can happen through drifting, bouncing, rolling, or leaching, which means the pesticide does not reach its target and pollutes the air, water, or soil. The pesticide controlled release system has good environmental responsiveness and can achieve precise quantitative release, which not only reduces the demand for pesticides in target crops and further improves pesticide utilization but also reduces the amount of pesticide residues in the soil and reduces the problem of environmental pollution. In addition, noncovalent interactions between pesticides and carriers play a significant role in pesticide controlled release systems. They can significantly improve the properties of pesticides, themselves, increase drug loading capacity, and enhance the stability of the system and the sensitivity of environmental stimulus-response. In this paper, the latest progress in constructing a pesticide controlled release system based on noncovalent interactions (hydrophobic interactions, hydrogen bonding interactions, electrostatic interactions, and supramolecular host–guest interactions) is summarized in detail, which provides a good foundation for developing an ideal pesticide controlled release system in the future.

Cattle slurry storage is a considerable source of pollutant emissions due to microbial degradation of its components and subsequent volatilization. These emissions are directly linked to losses of essential nutrients, which are consequently no longer available for further use (e.g., in biogas plants or for fertilization). Here, we present the correlation between the application of calcium cyanamide (CaCN₂) as an additive for efficient mitigation of emissions from cattle slurry storage and the conservation of nutrients. Three series of laboratory storage experiments were conducted using fresh cattle slurry with and without CaCN₂ under semiaerobic conditions at ambient temperature for 4 months each. Emission measurements and detailed mass balances, based on slurry analyses and weighing, revealed a considerable reduction in greenhouse gas emissions by 76.3% and concomitant preservation of fresh matter (34.9%), carbon (47.2%), and nitrogen (96.3%) upon facile additive application. Thus, CaCN₂ can enhance the value of cattle slurry despite prolonged storage.

Biochar effects on agricultural soils change over time as biochar ages. To better understand the long-term impacts of biochar application on climate change mitigation, the effect of biochar aging on nitrous oxide (N₂O) emissions has been widely investigated in field experiments. However, the underlying relationship of N₂O emissions with biochar properties, fertilization practices, soil properties, and weather conditions is poorly understood. We collected data from 30 peer-reviewed publications with 279 observations and used machine learning (ML) to model and explore critical factors affecting daily N₂O fluxes. We established and compared models constructed using neural networks (NN), support vector regression (SVR), random forest (RF), and extreme gradient boosting (XGB). We found that the gradient boosting regression (GBR) model was the optimal algorithm for predicting daily N₂O fluxes (R² > 0.90). The importance of factors driving daily N₂O fluxes is as follows: fertilization practices (44%) > weather conditions (30%) > soil properties (21%) > biochar properties (5%). In addition, the aging time of biochar, potassium application rate, soil clay fraction, and mean air temperature were critical factors affecting the daily N₂O fluxes. When biochar is initially applied, it can reduce N₂O emissions; however, it has no long-term effects in reducing N₂O emissions. The accurate prediction and insights from the ML model benefit the assessment of the long-term effects of biochar aging on N₂O emissions from agricultural soils.

Weed management strategies for specialty and organic crop production are challenging due to limited chemical weed control products with good efficacy that are cost-effective. The need for new bioherbicide modes of action has become increasingly urgent in modern agriculture, as most bioherbicides have nonspecific modes of action with no systemic activity. Introducing new modes of action is essential to diversifying weed control strategies, minimizing the risk of resistance development, and ensuring sustainable weed management practices. By fostering innovation in bioherbicide development and promoting the use of novel modes of action, we can safeguard our agricultural systems, reduce the environmental impact of weed management, and maintain the ability to feed a growing global population while preserving the long-term health of our ecosystems. Manuka oil is derived from the leaves and branches of the Manuka tree (Leptospermum scoparium) and contains β-triketones. The β-triketone-rich fraction contains leptospermone and inhibits a key enzyme, p-hydroxyphenylpyruvate dioxygenase (HPPD). This process directly inhibits carotenoid biosynthesis, upstream in the biochemical pathway, which causes damage to the photosynthetic apparatus and leads to bleaching of the leaf tissue, which eventually kills the plant. The β-triketone extract at 2% and 4% had up to 97% control against different weed species in field and greenhouse evaluations. The β-triketone extract was significantly more efficacious vs other bioherbicides such as 20% vinegar and 12.5% D-limonene. Additionally, the β-triketone extract was just as effective as a 2% glyphosate treatment in the greenhouse evaluation against Amaranthus palmeri and Digitaria sanguinalis. The β-triketone extract also reduced Cyperus esculentus growth by 70% at 9 days after treatment. Thus, there is significant evidence that commercializing a water-soluble β-triketone-enriched extract of Manuka oil can be an effective weed control strategy in crop production systems, especially in specialty and organic cropping systems where the need for bioherbicides is critically imperative.

Sichuan pepper, a pungent culinary spice, as well as a traditional medicinal plant, is widely used in Asian countries. Currently, pesticide combinations are still the most important tools for controlling insect pests to ensure the production of Sichuan pepper. However, there are limited data regarding the potential hazards posed by residues of these substances in Sichuan pepper products. In this study, a QuEChERS technique via UPLC-MS/MS for multianalysis of flonicamid and acetamiprid in fresh and dried Sichuan pepper was established with mean recoveries of 96–104%, relative standard deviations of ≤11%, and limits of quantifications of 0.01 mg/kg. A multisite field trial research was conducted to evaluate the persistence, processing factor, and dietary risk of flonicamid and acetamiprid in Sichuan pepper collected from four representative cultivation areas in China by the validated technique. The dynamic experiment indicated that flonicamid and acetamiprid degraded easily in Sichuan pepper with half-lives of 3.7–6.5 and 6.2–28.9 days, respectively. The residue concentrations of flonicamid and acetamiprid increased after the processing step with a processing factor higher than 1. The long-term dietary risk caused by residues of flonicamid and acetamiprid in Sichuan pepper is negligible, indicating that the application of these pesticides in Sichuan pepper cultivation was unlikely to pose adverse effects. Ultimately, in order to ensure food security, the maximum residue limits (MRLs) of flonicamid and acetamiprid were recommended at 1 and 2 mg/kg for dried Sichuan pepper, respectively, based on residue chemistry data and dietary assessment results. This study offers insights into the appropriate scientific application of the new commercial formulation in Sichuan pepper and contributes valuable data for the establishment of MRLs for flonicamid and acetamiprid in the future.

Natural and artificial radioactivity of agricultural soils poses significant environmental and health risks, necessitating detailed spatial analysis and hazard assessment. This study examines the spatial distribution of natural and artificial radionuclides (NOR and Cs-137), gross α and β activity, and in situ dose rates in agricultural soils through statistical and geostatistical techniques. NOR, Cs-137, and gross β activity exhibited high values and outliers, highlighting distinct distribution patterns. The Cs-137-altitude regression model consistently increased Cs-137 by 0.03 Bq/kg/m in height. Spatial distribution of natural radioactivity implies geology as a primary factor influencing the NOR distribution. However, analysis of spatial clusters and outliers unveiled geochemical variability for Ra-226 and Th-232, while the K-40 distribution appeared spatially random, potentially linked to agricultural activity. Additionally, a significant disparity in the distribution of K-40 by land use was identified, potentially attributable to potassium fertilizer application. Despite variability, average NOR values (394 Bq/kg for K-40, 22.5 Bq/kg for Ra-226, and 24.8 Bq/kg for Th-232) fall within UNSCEAR ranges. Gamma-emitting radionuclide-induced doses and risk primarily impacted nonresidential areas. These findings can be used in land use decisions, guide the development of contamination mitigation strategies to ensure safe agricultural practices, and help predict areas at risk of higher contamination for targeted remediation efforts.

The relationship between leaf symptoms caused by clopyralid and shoot concentrations of clopyralid was investigated by cultivating Pisum sativum L. At 1–10 μg/kg-dry weight (DW) of clopyralid in soil, the clopyralid concentrations in shoots increased up to 14 days and then decreased by 28 days after sowing. The fifth seedling leaf, which expressed the most serious symptoms, developed during the period when the shoot concentrations of clopyralid were at their highest and the symptoms in leaves formed after the fifth leaf became slightly less pronounced as the shoot clopyralid concentrations decreased. Thus, the severity of leaf symptoms depended on the shoot clopyralid concentration. The EC50 and EC10 values of clopyralid for P. sativum were calculated from the dose–response curve using an injury index based on the degree of leaf symptoms. The EC50 value was 30.9 μg/kg-DW (95% CI 28.4–33.4 μg/kg-DW), and the EC10 value was 3.2 μg/kg-DW (95% CI 2.2–4.1 μg/kg-DW), respectively. In addition, the dose–response curve obtained using the injury index increased from 1 μg/kg-DW of clopyralid in soil, confirming that the injury index could be used to estimate soil concentrations within a range that causes physiological disorders.

Neonicotinoid insecticides are widely employed in pest control, but their potential environmental implications demand the exploration of safer and more sustainable alternatives. This study encompasses a comprehensive assessment of the synthesis and toxicity of potential insecticide proline-derived chiral neonicotinoid derivatives, explicitly focusing on elucidating their environmental implications. Toxicity evaluation contained multiple models, including brine shrimp (Artemia salina), zebrafish (Danio rerio), and murine models compared with the commonly used insecticide dinotefuran. Enantioselective toxicity was observed in the brine shrimp assay, with the R-enantiomer demonstrating lesser toxicity compared to the S-enantiomer and dinotefuran. In the zebrafish model, dinotefuran induced developmental abnormalities, such as delayed hatching and vertebral column malformation, while the R-enantiomer exhibited relatively lower sensitivity. The murine LD₅₀ study in mice revealed lower toxicity levels for proline-derived insecticides than dinotefuran. Moreover, these chiral neonicotinoid derivatives were successfully synthesized by optimizing the synthetic routes. The synthesis involved specific starting materials and reaction steps, following established protocols. This study contributes valuable insights into the toxicity profiles of proline-derived chiral neonicotinoid derivatives and underscores the significance of assessing their environmental implications. The synthesized compounds provide a foundation for developing safer and more sustainable insecticides to mitigate the environmental risks associated with prevailing pest control practices.

The reliable measurement of the inorganic carbon content of soils and its changes resulting from land management practices and amendments is crucial for precisely quantifying carbon stocks as part of monitoring, reporting, and verification schemes. While various methods are available for evaluating the carbonate content in soils, the most direct approach is calcimetry, which involves the dissolution of solid-phase carbonates and the evolution of gas-phase CO₂ through acid-initiated reactions. Despite being a well-established method, uncertainties about how reliable calcimetry is to measure small changes in soil inorganic carbon (SIC) or how its measurement may be affected by potentially interfering reactions, sample size, and solid–liquid contact call for a dedicated investigation of these effects. The present study demonstrates the reliability of the calcimetry method and its limits through a parametric analysis that investigated the effect of the solid-to-liquid ratio, the presence of unweathered silicate phases, and the presence of copious amounts of organic matter. The results point to the reliable performance of calcimetry within the range of soil conditions that can be expected to be encountered during activities involving enhanced rock weathering and other best management practices that aim to boost the global soil carbon stocks as a climate change mitigation strategy.

This study examined the impact of sodium pyrosulfite (Na₂S₂O₅) as a silage additive on the fermentation, quality, microbial diversity, and metabolic function of sweet sorghum silage in saline–alkali soil. Sweet sorghum grown in local saline–alkali soil was harvested, defoliated, and sprayed with a Na₂S₂O₅ solution (contained 400–2000 ppm SO₂), vacuum-sealed, and fermented at 25 °C. Samples were stored for 0–64 days and analyzed for chemical composition and microbial diversity. After 8 days, the pH of all silages dropped below 3.8. The 16th day silage chemical analysis revealed Na₂S₂O₅ inhibiting ethanol and acetic acid production; S12 showed the best results: 5.497% total sugar, 2.357% lactic acid, 0.825% acetic acid, and 0.669% ethanol and achieved the highest silage quality scores (DB50/T 669-2016: 82, “Excellent”; DGL: 19, “Very Good”). Microbial analysis showed that Na₂S₂O₅ inhibited spoilage microbes, reduced sugar consumption by nonlactic acid bacteria (such as genus Rehenlla1), and promoted the fermentation of lactic acid bacteria, and the original pathogenic genus did not hinder lactic acid fermentation. Predominant genera like Rehenlla1 and Lactobacillus contributed the most to the key metabolic pathways of silage in the best treatment period.