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1.
Ecology ; 105(6): e4310, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38828716

ABSTRACT

Agricultural intensification has been identified as one of the key causes of global insect biodiversity losses. These losses have been further linked to the widespread use of agrochemicals associated with modern agricultural practices. Many of these chemicals are known to have negative sublethal effects on commercial pollinators, such as managed honeybees and bumblebees, but less is known about the impacts on wild bees. Laboratory-based studies with commercial pollinators have consistently shown that pesticide exposure can impact bee behavior, with cascading effects on foraging performance, reproductive success, and pollination services. However, these studies typically assess only one chemical, neglecting the complexity of real-world exposure to multiple agrochemicals and other stressors. In the summer of 2020, we collected wild-foraging workers of the common eastern bumblebee, Bombus impatiens, from five squash (Cucurbita) agricultural sites (organic and conventional farms), selected to represent a range of agrochemical, including neonicotinoid insecticide, use. For each bee, we measured two behaviors relevant to foraging success and previously shown to be impacted by pesticide exposure: sucrose responsiveness and locomotor activity. Following behavioral testing, we used liquid chromatography-tandem mass spectrometry (LC-MS/MS) chemical analysis to detect and quantify the presence of 92 agrochemicals in each bumblebee. Bees collected from our sites did not vary in pesticide exposure as expected. While we found a limited occurrence of neonicotinoids, two fungicides (azoxystrobin and difenoconazole) were detected at all sites, and the pesticide synergist piperonyl butoxide (PBO) was present in all 123 bees. We found that bumblebees that contained higher levels of PBO were less active, and this effect was stronger for larger bumblebee workers. While PBO is unlikely to be the direct cause of the reduction in bee activity, it could be an indicator of exposure to pyrethroids and/or other insecticides that we were unable to directly quantify, but which PBO is frequently tank-mixed with during pesticide applications on crops. We did not find a relationship between agrochemical exposure and bumblebee sucrose responsiveness. To our knowledge, this is the first evidence of a sublethal behavioral impact of agrochemical exposure on wild-foraging bees.


Subject(s)
Agrochemicals , Animals , Bees/drug effects , Bees/physiology , Agrochemicals/toxicity , Locomotion/drug effects , Insecticides/toxicity , Environmental Exposure
2.
Sci Rep ; 14(1): 13751, 2024 06 14.
Article in English | MEDLINE | ID: mdl-38877112

ABSTRACT

While spot spraying has gained increasing popularity in recent years, spot application of granule agrochemical has seen little development. Despite the potential for the technology, there currently exists no commercially available granular applicators capable of spot application. Therefore, the goal of this study was to design, build, and lab evaluate a precision applicator for spot applying granular agrochemical in wild blueberry. The design incorporated a John Deere RC2000 with a custom control box, recirculation system, and electrically actuated valves. All components were modified to fit a Valmar 1255 Twin-Roller. The system receives inputs from a predeveloped prescription map and can actuate each of the twelve valves separately to provide individual orifice control. Casoron® G4 was used as the testing agrochemical and in cycling the product pneumatically for 1 hour incurred no significant product degradation (p = 0.110). In lab evaluations, the applicator encountered zero errors in reading prescription maps and actuating the correct valves accordingly. Further, the granule recycling system had zero instances where product built up in the lines or jammed the valves. In all, this project represents the first successful development of a precision granular spot applicator for any cropping system.


Subject(s)
Agrochemicals , Blueberry Plants , Agrochemicals/pharmacology
3.
Sci Total Environ ; 945: 174075, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-38897461

ABSTRACT

The agricultural intensification represents a major threat to biodiversity, with negative effects on the ecosystem. In particular, habitat loss and degradation, along with pesticide use have been recognised as primary factors contributing to the actual global decline of pollinators. Here we investigated the quality of agroecosystems in the Emilia-Romagna region (Northern Italy) within the national monitoring project BeeNet. We analysed pesticide residues in 100 samples of beebread collected in 25 BeeNet stations in March and June 2021 and 2022. We evaluated diversity and concentration of these chemicals, their risk (TWC) to honey bees, and their correlation with land use. Overall, in 84 % of the samples we found 63 out of 373 different pesticide residues, >90 % of them belonging to fungicides and insecticides. The TWC exceeded the risk threshold in seven samples (TWCmix), mostly due to only one or two compounds. We also found 15 compounds not approved in the EU as plant protection products (PPPs), raising concerns about illegal use or contamination through beeswax recycling. Samples collected in 2021 and in June presented a significantly higher number of active ingredients and TWC than those collected in 2022 and in March. The TWC calculated on single compounds (TWCcom) exceeded the risk threshold in case of four insecticides, namely carbaryl, fipronil, imidacloprid and thiamethoxam (although each detected in only one sample). Finally, both TWC and number of active ingredients were moderately or highly positively correlated with the percentage of area covered by orchards. Considering that we found on average more than five different molecules per sample, and that we ignored potential synergistic effects, the results of this work highlight the alarming situation regarding pesticide treatments and toxicity risk for bees linked to the current agricultural practices, and the need for implementing sustainable and pollinator-friendly strategies.


Subject(s)
Agrochemicals , Environmental Monitoring , Pesticide Residues , Bees , Agrochemicals/analysis , Animals , Italy , Pesticide Residues/analysis , Agriculture , Insecticides/analysis
4.
J Appl Microbiol ; 135(7)2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38925655

ABSTRACT

AIMS: In this study, the antifungal efficacy and phytotoxicity of silica coated porous zinc oxide nanoparticle (SZNP) were analyzed as this nanocomposite was observed to be a suitable platform for slow release fungicides and has the promise to bring down the dosage of other agrochemicals as well. METHODS AND RESULTS: Loading and release kinetics of tricyclazole, a potent fungicide, were analyzed by measuring surface area (SBET) using Brunauer-Emmett-Teller (BET) isotherm and liquid chromatography tandem mass spectrometry (LC-MS/MS), respectively. The antifungal efficacy of ZnO nanoparticle (ZNP) and SZNP was investigated on two phytopathogenic fungi (Alternaria solani and Aspergillus niger). The morphological changes to the fungal structure due to ZNP and SZNP treatment were studied by field emission-scanning electron microscopy. Nanoparticle mediated elevation of reactive oxygen species (ROS) in fungal samples was detected by analyzing the levels of superoxide dismutase, catalase, thiol content, lipid peroxidation, and by 2,7-dichlorofluorescin diacetate assay. The phytotoxicity of these two nanostructures was assessed in rice plants by measuring primary plant growth parameters. Further, the translocation of the nanocomposite in the same plant model system was examined by checking the presence of fluorescein isothiocyanate tagged SZNP within the plant tissue. CONCLUSIONS: ZNP had superior antifungal efficacy than SZNP and caused the generation of more ROS in the fungal samples. Even then, SZNP was preferred as an agrochemical delivery vehicle because, unlike ZNP alone, it was not toxic to plant system. Moreover, as silica in nanoform is entomotoxic in nature and nano ZnO has antifungal property, both the cargo (agrochemical) and the carrier system (silica coated porous nano zinc oxide) will have a synergistic effect in crop protection.


Subject(s)
Antifungal Agents , Nanocomposites , Silicon Dioxide , Zinc Oxide , Zinc Oxide/pharmacology , Nanocomposites/toxicity , Silicon Dioxide/pharmacology , Silicon Dioxide/chemistry , Antifungal Agents/pharmacology , Agrochemicals/pharmacology , Aspergillus niger/drug effects , Aspergillus niger/growth & development , Oryza/microbiology , Oryza/growth & development , Oryza/drug effects , Fungicides, Industrial/pharmacology , Porosity , Plant Diseases/microbiology , Plant Diseases/prevention & control , Delayed-Action Preparations , Reactive Oxygen Species/metabolism
5.
Dalton Trans ; 53(25): 10553-10562, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38847020

ABSTRACT

Bismuth(III) complexes have been reported to act as inhibitors of the enzyme urease, ubiquitously present in soils and implicated in the pathogenesis of several microorganisms. The general insolubility of Bi(III) complexes in water at neutral pH, however, is an obstacle to their utilization. In our quest to improve the solubility of Bi(III) complexes, we selected a compound reported to inhibit urease, namely [Bi(HEDTA)]·2H2O, and co-crystallized it with (i) racemic DL-histidine to obtain the conglomerate [Bi2(HEDTA)2(µ-D-His)2]·6H2O + [Bi2(HEDTA)2(µ-L-His)2]·6H2O, (ii) enantiopure L-histidine to yield [Bi2(HEDTA)2(µ-L-His)2]·6H2O, and (iii) cytosine to obtain [Bi(HEDTA)]·Cyt·2H2O. All compounds, synthesised by mechanochemical methods and by slurry, were characterized in the solid state by calorimetric (DSC and TGA) and spectroscopic (IR) methods, and their structures were determined using powder X-ray diffraction (PXRD) data. All compounds show an appreciable solubility in water, with values ranging from 6.8 mg mL-1 for the starting compound [Bi(HEDTA)]·2H2O to 36 mg mL-1 for [Bi2(HEDTA)2(µ-L-His)2]·6H2O. The three synthesized compounds as well as [Bi(HEDTA)]·2H2O were then tested for inhibition activity against urease. Surprisingly, no enzymatic inhibition was observed during in vitro assays using Canavalia ensiformis urease and in vivo assays using cultures of Helicobacter pylori, raising questions on the efficacy of Bi(III) compounds to counteract the negative effects of urease activity in the agro-environment and in human health.


Subject(s)
Bismuth , Enzyme Inhibitors , Solubility , Urease , Bismuth/chemistry , Urease/antagonists & inhibitors , Urease/metabolism , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemical synthesis , Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Coordination Complexes/chemical synthesis , Agrochemicals/pharmacology , Agrochemicals/chemistry
6.
Stud Health Technol Inform ; 314: 178-182, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38785027

ABSTRACT

The characterization of local improved varieties as well as the reduction of synthetic chemical fertilizers are sustainable approaches in the vision of a new precision Farming. Aim of our study was to improve the geographical characterization of local ecotypes and to identify peculiar features of new crops in terms of bioactive compounds. NMR and LC-MS metabolite profiling approaches followed by multivariate data analysis were applied to characterize local rosemary and garlic ecotypes. With the aim of applying for a protected designation of origin, orthogonal partial least squares discriminant analysis (OPLS-DA) was used to identify representative sensory quality indicators for Vessalico garlic and rosemary "Eretto Liguria" local ecotypes, Variable Influence on Projections (VIP) values of OPLS-DA indicated six metabolites as quality indicators for Vessalico garlic and sixteen metabolites as quality indicators for rosemary "Eretto Liguria". Finally, to discover and utilize new ecotypes in a sustainable way, Vessalico garlic extracts antiviral activity, previously evaluated against Tomato brown rugose fruit virus (ToBRFV), a Tobamovirus affecting tomato crops, was extended to Pepino mosaic virus (PepMV) with positive results.


Subject(s)
Ecotype , Plant Extracts/therapeutic use , Garlic/chemistry , Rosmarinus/chemistry , Agrochemicals
7.
ACS Appl Mater Interfaces ; 16(22): 29305-29313, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38798175

ABSTRACT

Although agrochemical practices can enhance agricultural productivity, their intensive application has resulted in the deterioration of ecosystems. Therefore, it is necessary to develop more efficient and less toxic methods against pests and infections while improving crop productivity. Moving toward sustainable development, in this work, we originally described the preparation of a composite (ZIF-8@HA) consisting of the coating of zeolitic-like metal-organic framework (MOF) ZIF-8 (based on Zn, an essential micronutrient in plants with antibacterial, antifungal, and antifouling properties) with hydroxyapatite (HA) nanoparticles (i.e., nanofertilizer). The interaction between the HA and ZIF-8 has been characterized through a combination of techniques, such as microscopic techniques, where the presence of a HA coating is demonstrated; or by analysis of the surface charge with a dramatic change in the Z-potential (from +18.7 ± 0.8 to -27.6 ± 0.7 mV for ZIF-8 and ZIF-8@HA, respectively). Interestingly, the interaction of HA with ZIF-8 delays the MOF degradation (from 4 h for pristine ZIF-8 to 168 h for HA-coated material), providing a slower and gradual release of zinc. After a comprehensive characterization, the potential combined fertilizer and bactericidal effect of ZIF-8@HA was investigated in wheat (Triticum aestivum) seeds and Pseudomonas syringae (Ps). ZIF-8@HA (7.3 ppm) demonstrated a great fertilizer effect, increasing shoot (9.4 %) and root length (27.1 %) of wheat seeds after 11 days at 25 °C under dark conditions, improving the results obtained with HA, ZIF-8, or ZnSO4 or even physically mixed constituents (HA + ZIF-8). It was also effective in the growth inhibition (>80 % of growth inhibition) of Ps, a vegetal pathogen causing considerable crop decline. Therefore, this work demonstrates the potential of MOF@HA composites and paves the way as a promising agrochemical with improved fertilizer and antibacterial properties.


Subject(s)
Agrochemicals , Durapatite , Metal-Organic Frameworks , Durapatite/chemistry , Durapatite/pharmacology , Metal-Organic Frameworks/chemistry , Metal-Organic Frameworks/pharmacology , Agrochemicals/chemistry , Agrochemicals/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Nanoparticles/chemistry , Zeolites/chemistry , Zeolites/pharmacology , Triticum/chemistry , Triticum/drug effects , Imidazoles
8.
J Agric Food Chem ; 72(22): 12300-12318, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38800848

ABSTRACT

Scaffold structures, new mechanisms of action, and targets present enormous challenges in the discovery of novel pesticides. The discovery of new scaffolds is the basis for the continuous development of modern agrochemicals. Identification of a good scaffold such as triazole, carbamate, methoxy acrylate, pyrazolamide, pyrido-pyrimidinone mesoionic, and bisamide often leads to the development of a new series of pesticides. In addition, pesticides with the same target, including the inhibitors of succinate dehydrogenase (SDH), oxysterol-binding-protein, and p-hydroxyphenyl pyruvate dioxygenase (HPPD), may have the same or similar scaffold structure. Recent years have witnessed significant progress in the discovery of new pesticides using natural products as scaffolds or bridges. In recent years, there have been increasing reports on the application of natural benzopyran compounds in the discovery of new pesticides, especially osthole and coumarin. A systematic and comprehensive review of benzopyran active compounds in the discovery of new agricultural chemicals is helpful to promote the discussion and development of benzopyran active compounds. Therefore, this work systematically reviewed the research and application of benzopyran derivatives in the discovery of agricultural chemicals, summarized the antiviral, herbicidal, antibacterial, fungicidal, insecticidal, nematicidal and acaricidal activities of benzopyran active compounds, and discussed the structural-activity relationship and mechanism of action. In addition, some active fragments were recommended to further optimize the chemical structure of benzopyran active compounds based on reference information.


Subject(s)
Agrochemicals , Benzopyrans , Drug Discovery , Pesticides , Benzopyrans/chemistry , Benzopyrans/pharmacology , Pesticides/chemistry , Pesticides/pharmacology , Agrochemicals/chemistry , Agrochemicals/pharmacology , Animals , Structure-Activity Relationship , Molecular Structure
9.
J Am Soc Mass Spectrom ; 35(5): 1007-1011, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38613771

ABSTRACT

Formulating agrochemical products involves combining several chemical components, including the active ingredient(s), to obtain a final product with desirable efficacy. A formulated product incorporates additional components to modulate properties that enhance the efficacy of the active(s) by modifying physical properties such as viscosity, hydrophobicity, miscibility, and others. In plants, understanding the formulation's ability to spread on tissues and penetrate through the outer layer is critical in evaluating the efficacy of the final product. We have previously demonstrated the use of mass spectrometry imaging to determine spreadability. In this study, we show that laser ablation electrospray mass spectrometry (LAESI-MS) can be a valuable tool to assess the penetrability of formulations into the leaf tissues by selectively sampling various layers of leaf tissue by manipulating the laser intensity and analyzing the ablated material using a mass spectrometer. Using this technique, we were able to identify a formulation composition that can improve the penetration and uptake of active ingredients.


Subject(s)
Agrochemicals , Plant Leaves , Spectrometry, Mass, Electrospray Ionization , Plant Leaves/chemistry , Spectrometry, Mass, Electrospray Ionization/methods , Agrochemicals/analysis , Agrochemicals/chemistry
10.
Talanta ; 275: 126116, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38640518

ABSTRACT

Fragmentation characteristics are crucial for nontargeted screening to discover and identify unknown exogenous chemical residues in animal-derived foods. In this study, first, fragmentation characteristics of 51 classes of exogenous chemical residues were summarized based on experimental mass spectra of standards in reversed-phase and hydrophilic interaction liquid chromatography-high-resolution mass spectrometry (MS) and mass spectra from the MassBank of North America (MoNA) library. According to the proportion of fragmentation characteristics to the total number of chemical residues in each class, four screening levels were defined to classify 51 classes of chemical residues. Then, a nontargeted screening method was developed based on the fragmentation characteristics. The evaluation results of 82 standards indicated that more than 90 % of the chemical residues with MS/MS spectra can be identified at concentrations of 100 and 500 µg/kg, and about 80 % can be identified at 10 µg/kg. Finally, the nontargeted screening method was applied to 16 meat samples and 21 egg samples as examples. As a result, eight chemical residues and transformation products (TPs) of 5 classes in the exemplary samples were found and identified, in which 3 TPs of azithromycin were identified by fragmentation characteristics-assisted structure interpretation. The results demonstrated the practicability of the nontargeted screening method for routine risk screening of food safety.


Subject(s)
Food Analysis , Hazardous Substances , Liquid Chromatography-Mass Spectrometry , Food Analysis/instrumentation , Food Analysis/methods , Food Analysis/standards , Eggs/analysis , Meat/analysis , Food Safety , Databases, Chemical , Hazardous Substances/analysis , Agrochemicals/analysis , Molecular Structure , Animals
11.
Int J Biol Macromol ; 267(Pt 2): 131404, 2024 May.
Article in English | MEDLINE | ID: mdl-38582466

ABSTRACT

Chitosan has received much more attention as a functional biopolymer with applications in pharmaceuticals, agricultural, drug delivery systems and cosmetics. The objectives of present investigation were to carry out modification of chitosan for enhancement of aqueous solubility, which will impart increased solubility and dissolution rate of poorly soluble drug itraconazole (ITZ) and also evaluate the modified chitosan for soyabean seed germination studies. The modification of chitosan was accomplished through the antisolvent precipitation method; employing five carboxylic acids. The resulting products were assessed for changes in molecular weight, degree of deacetylation, solubility and solid state characterization. Subsequently, the modified chitosan was complexed with itraconazole using the co-grinding technique. The prepared formulations were evaluated for solubility, FTIR (Fourier-transform infrared spectroscopy), PXRD (Powder X-ray diffraction), in-vitro dissolution studies. Furthermore the effect of modified chitosan has been evaluated on soybean seed germination. Results demonstrated that, modified chitosan improves self and solubility of itraconazole by six folds. As there was increased degree of deacetylation of chitosan leads to improvement in solubility. The results of FTIR showed the slight shifting of peaks in co-grind formulations of itraconazole. Formulations showed reduction in crystallinity of drug which leads to enhancement in dissolution rate as compared to pure itraconazole. Retention of property of seed germination was observed with modified chitosan at optimum concentration of 3 % w/v, with benefit of enhanced aqueous solubility of chitosan. This positive result paves the way for the advancement of pharmaceutical and agrochemical products employing derivatives of chitosan.


Subject(s)
Agrochemicals , Chitosan , Itraconazole , Solubility , Chitosan/chemistry , Agrochemicals/chemistry , Agrochemicals/pharmacology , Itraconazole/chemistry , Itraconazole/pharmacology , Glycine max/chemistry , Germination/drug effects , Seeds/chemistry , Seeds/drug effects , Chemical Phenomena , Spectroscopy, Fourier Transform Infrared , Molecular Weight , X-Ray Diffraction
12.
J Agric Food Chem ; 72(19): 10710-10724, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38688008

ABSTRACT

The human population will be approximately 9.7 billion by 2050, and food security has been identified as one of the key issues facing the global population. Agrochemicals are an important tool available to farmers that enable high crop yields and continued access to healthy foods, but the average new agrochemical active ingredient takes more than ten years, 350 million dollars, and 20,000 animals to develop and register. The time, monetary, and animal costs incentivize the use of New Approach Methodologies (NAMs) in early-stage screening to prioritize chemical candidates. This review outlines NAMs that are currently available or can be adapted for use in early-stage screening agrochemical programs. It covers new in vitro screens that are on the horizon in key areas of regulatory concern. Overall, early-stage screening with NAMs enables the prioritization of development for agrochemicals without human and environmental health concerns through a more directed, agile, and iterative development program before animal-based regulatory testing is even considered.


Subject(s)
Agrochemicals , Humans , Animals
13.
Int J Mol Sci ; 25(7)2024 Apr 04.
Article in English | MEDLINE | ID: mdl-38612824

ABSTRACT

The intention of this Special Issue is to focus on new achievements in the design, preparation, and in vitro and in vivo biological evaluation of bioactive molecules that can result in the development of natural or artificial potent compounds looking for promising pharmaceuticals and agrochemicals [...].


Subject(s)
Agrochemicals
14.
Nat Commun ; 15(1): 3188, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38609402

ABSTRACT

Halogen-containing molecules are ubiquitous in modern society and present unique chemical possibilities. As a whole, de novo fermentation and synthetic pathway construction for these molecules remain relatively underexplored and could unlock molecules with exciting new applications in industries ranging from textiles to agrochemicals to pharmaceuticals. Here, we report a mix-and-match co-culture platform to de novo generate a large array of halogenated tryptophan derivatives in Escherichia coli from glucose. First, we engineer E. coli to produce between 300 and 700 mg/L of six different halogenated tryptophan precursors. Second, we harness the native promiscuity of multiple downstream enzymes to access unexplored regions of metabolism. Finally, through modular co-culture fermentations, we demonstrate a plug-and-play bioproduction platform, culminating in the generation of 26 distinct halogenated molecules produced de novo including precursors to prodrugs 4-chloro- and 4-bromo-kynurenine and new-to-nature halogenated beta carbolines.


Subject(s)
Escherichia coli , Tryptophan , Escherichia coli/genetics , Fermentation , Kynurenine , Agrochemicals
15.
Environ Res ; 252(Pt 2): 118975, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38649018

ABSTRACT

Understanding the impact of various agricultural chemical components on the fate and transport of microplastics (MPs) in the subsurface is essential. In this study, column experiments on saturated porous media were conducted to explore the influence of the coexistence environment of pesticide adjuvants (surfactants) and active ingredients (neonicotinoids) on the transport of polyethylene (PE) and polypropylene (PP) MPs. An anionic surfactant (sodium dodecyl sulfate (SDS)), a nonionic surfactant (nonylphenol ethoxylate (NP-40)), and three neonicotinoid insecticides (acetamiprid, dinotefuran, and nitenpyram) could independently increase MP migration by 9.31%-61.01% by improving the hydrophilicity. Acetamiprid or dinotefuran reduced the adhesion work of the binary system by competing with SDS for adsorption sites, thereby inhibiting PE mobility. However, nitenpyram in the mixture was not easily adsorbed on the surface of PE MPs together with SDS because of nitenpyram's high hydrophilicity. Neonicotinoid molecules could not reduce the hydrophilic modification of SDS on PP MPs by competing for adsorption sites. Owing to their weak charge and adhesion work of nonionic surfactants (-4.80 mV and 28.45 kT for PE and -8.21 mV and 17.64 kT for PP), neonicotinoids tended to occupy the adsorption sites originally belonging to NP-40. The long molecular chain of NP-40 made it difficult for high-concentration neonicotinoids to affect the adhesion on MPs. In addition, NP-40 was harder to peel off from the MP surface than SDS, leading to a larger MP transport ability in the sand column.


Subject(s)
Microplastics , Polyethylene , Polypropylenes , Surface-Active Agents , Polypropylenes/chemistry , Polyethylene/chemistry , Microplastics/chemistry , Surface-Active Agents/chemistry , Adsorption , Pesticides/chemistry , Neonicotinoids/chemistry , Agrochemicals/chemistry , Insecticides/chemistry , Water Pollutants, Chemical/chemistry
16.
Pest Manag Sci ; 80(8): 4044-4054, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38563464

ABSTRACT

BACKGROUND: The hydraulic spray delivery (HSD)-based solid set canopy delivery system (SSCDS) emitter configuration has been optimized for agrochemical applications in vertical shoot position (VSP) vineyards. It uses cost-prohibitive emitters, and their placement restricts the mechanical pruning activities. Therefore, this study focused on optimizing the spray performance of a pneumatic spray delivery (PSD)-based SSCDS variant that addresses the earlier issues. Three PSD-SSCDS emitter configurations (C1-C3) were designed using modified low-cost emitters (E1: modified flat fan, E2: 90° modular flat fan) for agrochemical applications in VSP vineyards. C1 had an E1 installed on trellis posts at 1.67 m above ground level. C2 had a pair of E2 installed per vine at 0.3 m below the cordon, while C3 combined the emitter placement of C1 and C2. The spray deposition (ng cm-2) and coverage (%) were quantified (mean ± standard error) using mylar cards and water-sensitive paper samplers placed within the canopy, respectively. RESULTS: Spray deposition for C1, C2, and C3 was 301.12 ± 63.30, 347.9 ± 66.29, and 837.6 ± 92.53 ng cm-2, respectively. Whereas spray coverage for corresponding configurations was 18.02 ± 2.63, 8.98 ± 1.84, and 28.84 ± 2.46%, respectively. CONCLUSIONS: Overall, configuration C3 provided significantly higher spray deposition and coverage than C1 and C2. Substantially reduced system installation cost and emitter density per hectare with improved spray performance were achieved by C3 compared to earlier optimized HSD-SSCDS configuration in the VSP vineyards. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Subject(s)
Vitis , Agrochemicals/pharmacology , Farms , Pesticides
17.
Int. microbiol ; 27(2): 631-643, Abr. 2024. graf
Article in English | IBECS | ID: ibc-232307

ABSTRACT

As an alternative to chemical insecticides, gut bacteria of insects could be used to control insect pests. In this study, bacteria associated with Tuta absoluta, an invasive species that has developed resistance to chemical insecticides, were isolated, and their potential for pest control was investigated. We isolated 13 bacteria from larvae of the pest and identified the isolates on the basis of their morphological, physiological, biochemical, and molecular characteristics as Bacillus thuringiensis (Ta1-8), Staphylococcus petrasii (Ta9), Citrobacter freundii (Ta10), Chishuiella changwenlii (Ta11), Enterococcus casseliflavus (Ta12), and Pseudomonas tremae (Ta13). A laboratory screening test at 109 cfu/ml showed that B. thuringiensis (Bt) isolates caused more than 90% mortality after 3 days. Among the isolates, Bt-Ta1 showed the highest mortality in a short time. The LC50 and LC90 values for Bt-Ta1 were estimated to be 1.2 × 106 and 2 × 109 cfu/ml, respectively. Detailed characterization of Bt-Ta1 revealed that it is one of the serotypes effective on lepidopterans and contains the genes cry1Aa, cry2Aa, and vip3Aa, which encode lepidopteran toxic proteins. Bt-Ta1 isolate has been shown to have the potential to be used in the integrated management of Tuta absoluta. (AU)


Subject(s)
Insecticides , Agrochemicals , Bacteria , Insecta , Agricultural Pests
18.
J Agric Food Chem ; 72(12): 6702-6710, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38484107

ABSTRACT

The discovery of novel and easily accessible antifungal compounds is an imperative issue in agrochemical innovation. Our continuing research with the o-aminophenyloxazoline (NHPhOx) scaffold demonstrated the viability of introducing phenylacetamides for identifying novel antifungal leads. An antifungal function-oriented molecular evaluation was conducted for the previously identified lead R-LE008. Fine-tuning of the α-position and scaffold hopping of acid segment and NHPhOx enables α-oximido-arylacetamide as a novel antifungal model. The concomitant function-oriented diversification produces a panel of antifungal leads CN19, CN21b, CN28, and CN31 against Sclerotinia sclerotiorum and Botrytis cinerea. The crucial and multidimensional effect of the configuration of the acquired amides on the antifungal performance is demonstrated specifically by the separable CN21 isomers. The Z-isomer (CN21b), with an EC50 value of 0.97 µM against B. cinerea, is significantly more potent than its E-isomer (CN21a) and the positive control boscalid. More importantly, compound CN21b can efficiently inhibit resistant B. cinerea strains. CN21b demonstrates a better in vivo preventative effect (82.1%) than those of CN21a (48.1%) and boscalid (55.1%) at 100 µM. CN21b showed a distinct binding model from those of the boscalid and CN21a in the molecular docking simulation. A further morphological investigation by scanning electron microscopy revealed the different mycelia shrinkage of B. cinerea treated by CN21 isomers. The easy accessibility and cost-effectiveness demonstrated the practical potential of α-oximido-phenylacetamide containing NHPhOx as a new model for agrochemical innovation.


Subject(s)
Antifungal Agents , Biphenyl Compounds , Fungicides, Industrial , Niacinamide/analogs & derivatives , Antifungal Agents/pharmacology , Molecular Structure , Structure-Activity Relationship , Molecular Docking Simulation , Botrytis , Agrochemicals/pharmacology , Fungicides, Industrial/chemistry
19.
J Agric Food Chem ; 72(12): 6684-6690, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38485919

ABSTRACT

Based on natural cerbinal, a series of novel 4-bit modified cyclopenta[c]pyridine derivatives containing a substituted amide or ester moiety were designed and synthesized for the first time. Their structures were systematically characterized by NMR and high-resolution mass spectra (HRMS). The anti-TMV activities, such as protection, inactivation, and curative effects in vivo, were evaluated methodically. The lethal activities of the target compounds against the agriculturally common pests Plutella xylostella larvae and Aphis laburni kaltenbach were evaluated by the immersion method. The bioassay results indicated that most of the target compounds exhibited good to excellent anti-TMV activity levels, good lethal activity against P. xylostella larvae at 600 µg/mL, and greater insecticidal activities against A. laburni Kaltenbach compared to the plant-derived insecticide rotenone. The binding mode of cerbinal and cyclopenta[c]pyridine derivatives 4b, 4p, and 4v with the TMV protein was studied with a molecular docking method, which indicated that the functional group of the 2- and 4-positions is vital for anti-TMV activity. The systematic research provides strong evidence that these novel 4-bit modified cyclopenta[c]pyridine derivatives could become potential agrochemical insecticides and anti-TMV agents.


Subject(s)
Indenes , Insecticides , Tobacco Mosaic Virus , Insecticides/chemistry , Structure-Activity Relationship , Agrochemicals/pharmacology , Antiviral Agents/pharmacology , Molecular Docking Simulation , Drug Design , Pyridines/chemistry , Molecular Structure
20.
J Agric Food Chem ; 72(14): 7672-7683, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38530782

ABSTRACT

Agrochemical residues and nitrous oxide (N2O) emissions have caused considerable threats to agricultural soil ecology. Nanoscale zerovalent iron (nZVI) and nitrification inhibitors might be complementary to each other to diminish soil agrochemical residues and N2O emissions and enhance soil bacterial community diversities. Compared to the control, the nZVI application declined soil paclobutrazol residues by 5.9% but also decreased the bacterial community co-occurrence network node. Combined nZVI and Dicyandiamide applications significantly decreased soil N2O emission rates and paclobutrazol residues but promoted Shannon diversity of the bacterial community. The increased soil pH, ammonium nitrogen, and Actinobacteriota could promote soil paclobutrazol dissipation. The nZVI generated double-edged sword effects of positively decreasing paclobutrazol residues and N2O emissions but negatively influencing soil multifunctionalities. The nZVI and Dicyandiamide could be complementary to each other in diminishing soil agrochemical residues and N2O emission rates but promoting soil bacterial community diversities simultaneously.


Subject(s)
Guanidines , Nitrous Oxide , Soil , Triazoles , Soil/chemistry , Nitrous Oxide/chemistry , Nitrification , Agriculture , Bacteria/genetics , Fertilizers/analysis , Agrochemicals/pharmacology , Nitrogen/chemistry
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