ACS agricultural science & technology最新文献

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.

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.

Microneedles, which are small needle-shaped devices, have gained attention as versatile tools with applications across various fields owing to their precision and minimal invasiveness. In the literature, the integration of microneedle technology into agricultural domains has been explored, particularly focusing on the real-time monitoring of precise agrochemical delivery and crop biosensing in situ. In this study, we summarize representative microneedle types and corresponding fabrication techniques. Then, we discuss the advantages of microneedles in plant health management and drug delivery, as well as related challenges, such as safety and mass production. The agricultural applications of microneedles can potentially overcome the limitations of traditional methods and offer innovative solutions for crop disease management. This study demonstrates that microneedles present innovative possibilities in agriculture and contribute to the improvement of sustainable agriculture.

In order to solve the insufficiency of traditional pesticide residue detection methods, such as limited detection sensitivity, high time and labor costs, inability to monitor in real time, and easy interference of detection results, a study that combines a microfluidic platform with surface-enhanced Raman scattering (SERS) technology to enable rapid detection of continuous trace amounts is proposed. The microfluidic SERS chip utilizes porous silicon carbide impregnated with silver nanoparticles to construct a high-performance SERS substrate. The three-dimensional structure of porous silicon carbide gives the SERS substrate excellent enhancement performance, with a detection limit as low as 10^–12 M. Its high sensitivity and environmental friendliness makes it a promising tool for biochemical analysis and detection. The porous silicon carbide SERS substrate exhibits a high enhancement factor (EF) of 2.05 × 10¹³ for the R6G solution at 1506 cm^–1.

In recent years, convolutional neural network (CNN) models and deep learning techniques have gained significant attention for plant disease detection. Despite advances, achieving high accuracy across diverse classes remains challenging. Existing CNN models have demonstrated moderate accuracy in classifying a limited number of mango leaf diseases. So, a crucial necessity exists to broaden the scope of precision. Our investigation introduces a CNN model that achieves an impressive 99% accuracy across eight classes of mango leaf diseases. Using advanced data processing, image augmentation, and feature extraction methodologies rooted in artificial intelligence and deep learning, we systematically explored over 20 CNN architectures and various hyperparameters to develop a robust model. Given the global significance of mango cultivation, our model was rigorously trained and tested for reliability. Detailed results and materials are available on GitHub. Additionally, we integrated our CNN model into an Android app, “Mango-SCN”, designed for easy use in managing mango leaf diseases, accessible even to nonexperts.

Many of the carriers used in the delivery of avermectin (Avm) B1a, a widely used crop pesticide, may lead to environmental safety problems. Here, we tested the self-assembly of Avm B1a without an exogenous excipient for improved environmental safety and drug activity. Our results showed that various solvents, including ethanol, methanol, acetone, dimethyl sulfoxide, and N,N-dimethylformamide, can be used to prepare Avm B1a self-assembled nanoparticles. Nuclear magnetic titration experiments revealed that the intermolecular hydrogen bond was the main binding force in Avm B1a self-assembly. Molecular dynamics simulations indicated that the number of hydrogen bonds increased to 10 and 20 in the assembly system of 16 and 32 Avm B1a molecules, respectively, over a period of 500 ns. The assembled Avm B1a presented a structured spherical shape, and particle size could be effectively regulated with the initial concentration. The permeability in soil and anti-UV degradation capacity were, respectively, 3.5 and 2.0 times higher for self-assembled nanoparticles with a size of 128 nm than for pure Avm B1a. The activity of nanoparticles against potato putrid stem nematode was higher than that of pure Avm B1a; in that, particles with a size of 128 nm exhibited the highest activity, and the 24 h and 48 h activity was, respectively, 16 and 20% higher than that of pure Avm B1a. In vivo fluorescence experiments showed that the fluorescence in nematodes increased with the increase in chemical concentration and time.