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Journal of Hazardous Materials Oct 2020Athetis lepigone is one of the most severe polyphagous pests, and it has developed resistance to different chemical insecticides. Insects primarily rely on the olfactory...
Athetis lepigone is one of the most severe polyphagous pests, and it has developed resistance to different chemical insecticides. Insects primarily rely on the olfactory system to recognize various environmental chemicals, including xenobiotics such as insecticides. Here, we expressed two A. lepigone pheromone-binding proteins (AlepPBP2 and AlepPBP3), and observed they had higher binding affinities to phoxim than other insecticides, with Ki was 3.30 ± 0.38 μM and 3.27 ± 0.10 μM, respectively. Molecular dynamics simulation, binding mode analysis, and computational alanine scanning showed that six residues (Phe15, Phe39, Ile55, Leu65, Ile97, and Phe122) of AlepPBP2 and three residues (Phe12, Ile52, and Ile134) of AlepPBP3 maybe as potential residues that can change protein ability to bind an organophosphorus insecticide phoxim. Then, we used site-directed mutagenesis assay to mutate these residues into alanine, respectively. Subsequently, the binding assays displayed that Phe15, Phe39, and Ile97 of AlepPBP2, Phe12 and Ile134 of AlepPBP3 caused a significant decrease of AlepPBPs binding ability to phoxim, suggesting they should play crucial roles in the AlepPBPs/phoxim interactions. Our findings could further advance in using PBPs as unique targets to design and develop precise and environmentally-friendly pest control agents with high insecticidal potential using a computer-aided drug design (CADD) approach.
Topics: Animals; Carrier Proteins; Insect Proteins; Insecticides; Olfaction Disorders; Pheromones
PubMed: 32388456
DOI: 10.1016/j.jhazmat.2020.122777 -
Zhongguo Zhong Yao Za Zhi = Zhongguo... Mar 2022The demand for Angelicae Sinensis Radix, the dry root of Angelica sinensis, has been increasing year by year. However, the continuous cropping obstacles, frequent...
The demand for Angelicae Sinensis Radix, the dry root of Angelica sinensis, has been increasing year by year. However, the continuous cropping obstacles, frequent occurrence of pests and diseases, overuse of chemical pesticides, excessive pesticide residues and other problems in Angelicae Sinensis Radix production have attracted much attention. In this paper, we summarized the common diseases and pests attacking Angelica sinensis as well as the detection methods and characteristics of pesticide residues in Angelicae Sinensis Radix from 2002 to 2021. Additionally, we compared the limit standards of pesticide residues in Angelicae Sinensis Radix in and out of China and put forward suggestions for the high-quality and green development of Angelicae Sinensis Radix industry conside-ring the existing problems. The pesticide residues in Angelicae Sinensis Radix have been changing from organochlorines to organophosphorus pesticides. In recent years, some organophosphorus pesticides such as phorate, phoxim, isofenphos-methyl, phorate-sulfoxide, fenamiphos, isocarbophos, omethoate, and triazophos in Angelicae Sinensis Radix have seriously exceeded the standards. The detection methods of pesticide residues has evolved from chromatography to high performance chromatography-mass spectrometry, gas chromatography-mass spectrometry(GC-MS), and liquid chromatography-mass spectrometry(LC-MS), and some new detection techniques such as immunoassay have also been applied. Pesticide residues have become a primary factor that restricting the development of Angelicae Sinensis Radix industry. Therefore, moderate application of pesticides, establishment of ecological planting system, and strict limit standards of pesticide residues are necessary to solve the pesticide residue problem.
Topics: Angelica sinensis; Chromatography, Liquid; Organophosphorus Compounds; Pesticide Residues; Pesticides
PubMed: 35347942
DOI: 10.19540/j.cnki.cjcmm.20211220.102 -
Veterinary Sciences Sep 2022The poultry red mite Dermanyssus gallinae is the most important blood-sucking ectoparasite in egg-laying hen facilities. The aim of this study was to evaluate the in...
The poultry red mite Dermanyssus gallinae is the most important blood-sucking ectoparasite in egg-laying hen facilities. The aim of this study was to evaluate the in vitro acaricidal activity of different concentration of authorized (phoxim, ByeMite®, 500 mg/mL) and unauthorized (fipronil, Frontline® 250 mg/100 mL spray) molecules on 14 field isolates of D. gallinae collected from different ornamental poultry farms from different Italian regions. The sensitivity test was performed by contact exposure to four concentrations of each insecticide diluted at 1:5 (10,000-2000-400-80 ppm for phoxim, 500-100-20-4 ppm for fipronil) on a filter paper. The effectiveness of the treatment was significantly (p < 0.0001) associated with the dose of the pesticide used. Considering the mean lethality, phoxim has greater efficacy compared to fipronil (p < 0.001). A great variability of lethality rate was observed with the increase in fipronil dilution; conversely, for phoxim, some outliers were observed, particularly in one farm, suggesting the hypothesis that a certain degree of resistance in the mite population could occur possibly as a consequence of the continual contact with the molecule. This underlines the importance of the use of licensed products administered at correct dosages and the need for alternative molecules to avoid the onset of drug resistance phenomena.
PubMed: 36136703
DOI: 10.3390/vetsci9090486 -
Avian Pathology : Journal of the W.V.P.A Sep 2019(De Geer, 1778) is a major problem for the poultry industry worldwide, as it negatively affects virtually all kinds of rearing systems. Therefore, the control of...
(De Geer, 1778) is a major problem for the poultry industry worldwide, as it negatively affects virtually all kinds of rearing systems. Therefore, the control of infestation has become a routine process, and its economic cost is constantly increasing. Until now, most of the control strategies have relied on the use of synthetic chemical drugs, but their efficacy is often questioned by the emergence and diffusion of resistant mite populations. With this in mind, the efficacy of -cyhalothrin, amitraz, and phoxim has been verified by testing them against 86 mite populations collected from the same number of poultry farms in Italy from 2008 to 2015. Assays were performed according to the filter paper method using the recommended, half, quarter, double and quadruple doses. The results showed that phoxim and amitraz were the most effective acaricides (median efficacies 80.35% and 80.83%, respectively), but amitraz exhibited a sharp fall in its efficacy during 2011 and 2012, while phoxim maintained its high effectiveness up to 2015, when it dropped. The overall median efficacy of -cyhalothrin was 58.33%. The data also highlighted the importance of the use of the right concentration, as an increase in dosage was not always useful against resistant populations, while its reduction also diminished efficacy, simultaneously increasing the risk for the development of resistance.
Topics: Acaricides; Animals; Italy; Mite Infestations; Mites; Nitriles; Organothiophosphorus Compounds; Poultry; Poultry Diseases; Pyrethrins; Surveys and Questionnaires; Toluidines
PubMed: 31362523
DOI: 10.1080/03079457.2019.1645295 -
Bacterial communities in natural versus pesticide-treated Aphis gossypii populations in North China.MicrobiologyOpen Mar 2019The cotton-melon aphid, Aphis gossypii Glover, is a worldwide-spreading species, and pesticide-resistant populations are increasing rapidly. In this study,...
The cotton-melon aphid, Aphis gossypii Glover, is a worldwide-spreading species, and pesticide-resistant populations are increasing rapidly. In this study, investigations were performed based on Illumina HiSeq sequencing of the 16S rDNA V4 region for the bacterial communities embodied as intracellular symbionts under natural and in pesticide-treated populations of A. gossypii. The results revealed that more than 82% of bacterial communities belonged to the phylum Proteobacteria in which the maximum proportion (53.24%) was of the genus Arsenophonus; Hamiltonella composed 22.31; and 1.37% was of the genus Acinetobacter. The relative abundance of Hamiltonella was obvious, vertically transmitted, divided into two groups, and its infection influenced the bacterial communities in A. gossypii. Symbiont density and composition were changed in samples tested on different days. Azadirachtin and phoxim influenced on the composition of bacterial communities. Different biomarkers were used for pesticide-treated samples with LEfSe results. These findings will increase awareness regarding bacterial communities in naturally occurring populations of A. gossypii and pave the way to study the relationship between symbionts and pesticide resistance.
Topics: Animals; Aphids; China; Cluster Analysis; DNA, Bacterial; DNA, Ribosomal; Microbiota; Pesticides; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA
PubMed: 29877631
DOI: 10.1002/mbo3.652 -
Foods (Basel, Switzerland) Mar 2023Pesticide residues in aquatic products are of great concern due to the risk of environmental transmission and their extensive use in aquaculture. In our work, a quick...
Pesticide residues in aquatic products are of great concern due to the risk of environmental transmission and their extensive use in aquaculture. In our work, a quick screening approach was developed for the qualitative and semi-quantitative screening of 87 pesticide residues in aquatic products. The sample preparation was investigated, including extract solvent, extract methods, buffer salts, lipid removal, cleanup materials and filter membranes for aquatic products. Samples were extracted using a modified QuEChERS procedure, and two clean-up procedures were developed for UHPLC-Q/Orbitrap MS analysis based on the fat content of the aquatic products. The screening detection limits for all studied pesticides were distributed between 1 and 500 μg/kg in the three representative matrices. Seventy-one pesticides could be analyzed with a screening limit between 1 and 25 μg/kg in grass carp and crayfish, sixty-one pesticides could be screened for limits between 1 and 50 μg/kg in crab. The accuracy results showed that recoveries ranged from 50 to 120% for 60, 56 and 52 pesticides at medium-level for grass carp, crayfish and crab, respectively. At high spiking levels, 74, 65 and 59 pesticides were recovered within the range of 50-120% for the three matrices, respectively. The relative standard deviations of most compounds in different matrices were less than 20%. With this method, the local farmed aquatic products were tested for pesticide residues. In these samples, ethoxyquinoline, prometryn and phoxim were frequently detected. The majority of these confirmed compounds did not exceed 2.00 μg/kg. A grass carp with trichlorfon at 4.87 μg/kg and two carps with ethoxyquinoline at 200 µg/kg were detected, indicating the potential dietary risk.
PubMed: 36981058
DOI: 10.3390/foods12061131 -
Bulletin of Entomological Research Feb 2022Parasitoid wasps are key agents for controlling insect pests in integrated pest management programs. Although many studies have revealed that the behavior of parasitic...
Parasitoid wasps are key agents for controlling insect pests in integrated pest management programs. Although many studies have revealed that the behavior of parasitic wasps can be influenced by insecticides, the strategies of patch time allocation and oviposition have received less attention. In the present study, we forced the endoparasitoid Meteorus pulchricornis to phoxim exposure at the LC30 and tested the foraging behavior within patches with different densities of the host, the larvae of the tobacco cutworm Spodoptera litura. The results showed that phoxim treatment can significantly increase the patch-leaving tendency of female wasps, while host density had no impact. The number of oviposition and the number of previous patch visits also significantly influenced the patch time allocation decisions. The occurrence of oviposition behavior was negatively affected by phoxim exposure; however, progeny production was similar among patches with different host densities. Phoxim exposure shaped the offspring fitness correlates, including longer durations from cocoon to adult wasps, smaller body size, and shorter longevity. The findings of the present study highlight the sublethal effects that reduce the patch residence time and the fitness of parasitoid offspring, suggesting that the application of phoxim in association with M. pulchricornis should be carefully schemed in agroecosystems.
Topics: Animals; Female; Host-Parasite Interactions; Insecticides; Larva; Organophosphorus Compounds; Organothiophosphorus Compounds; Oviposition; Wasps
PubMed: 34425923
DOI: 10.1017/S0007485321000614 -
Chemosphere Feb 2024This review addresses the impact of various chemical entities like pesticides, antibiotics, nanoparticles and microplastic on gut microbiota of zebrafish. Gut microbiota... (Review)
Review
Exploring the impact of antibiotics, microplastics, nanoparticles, and pesticides on zebrafish gut microbiomes: Insights into composition, interactions, and health implications.
This review addresses the impact of various chemical entities like pesticides, antibiotics, nanoparticles and microplastic on gut microbiota of zebrafish. Gut microbiota plays a vital role in metabolic regulation in every organism. As majority of metabolic pathways coordinated by microbiota, small alterations associated with mild to serious outcomes. Because of their unstoppable usage in day-to-day life, the present-day research on gut microbiota is mostly comprising aforementioned chemicals. It is better to understand how gut microbiome is dysbiosed by various environmental factors, to keep our microbiota safe. We tried to delineate the natural flora of zebrafish gut microbiome and the metabolic and other pathways associated and what are the common flora that was dysbiosed during the treatment. Based on the existing literature, we reviewed pesticides like Imazalil, Difenoconazole, Chlorpyrifos, Metamifop, Carbendazim, Imidacloprid, Phoxim, Niclosamide, Dieldrin, and antibiotics like Oxytetracycline, Enrofloxacin, Florfenicol, Sulfamethoxazole, Tetracycline, Streptomycin, Doxycycline, and in the category of nanoparticles, Titanium dioxide nanoparticles (nTiO2), Abalone viscera hydrolysates decorated silver nanoparticles (AVH-AgNPs), Lead-halide perovskite nanoparticles (LHP NPs), Copper nanoparticles (Cu-NPs), silver nanoparticles (Ag-NPs) and microplastic types like polyethylene and polystyrene microplastic. Other studies with miscellaneous chemical entities on zebrafish gut microbiome include Ferulic acid, Polychlorinated biphenyls, Cadmium, Disinfection by-products, Triclosan, microcystin-LR, Fluoride, and Amitriptyline.
Topics: Animals; Gastrointestinal Microbiome; Plastics; Zebrafish; Metal Nanoparticles; Pesticides; Microplastics; Anti-Bacterial Agents; Silver
PubMed: 38048833
DOI: 10.1016/j.chemosphere.2023.140867 -
Gene Jul 2018Folate metabolism pathway is mainly associated with syntheses of nucleic acids and proteins as well as DNA methylation and repair. Cytoplasmic C tetrahydrofolate (C-THF)...
Folate metabolism pathway is mainly associated with syntheses of nucleic acids and proteins as well as DNA methylation and repair. Cytoplasmic C tetrahydrofolate (C-THF) synthase is a central enzyme in folate metabolism and plays an important role in C-THF conversion. The full-length sequence of silkworm (Bombyx mori) cytoplasmic C-THF synthase (BmC-THF synthase) gene including an open reading frame (ORF) of 932 amino acid residues was cloned. Phylogenetic analysis indicated that BmC-THF synthase shares 84% and 81% identity with C-THF synthase of Papilio Xuthus and Danaus plexippus, respectively. Conserved sequence analysis showed that the 330 to 710 amino acid residues of BmC-THF synthase were highly conserved among various organisms. Recombinant BmC-THF synthase protein with a molecular weight of about 105.5 kDa was expressed in E. coli cells and identified using SDS-PAGE and western blot analysis. The expression of BmC-THF synthase gene in eight silkworm tissues revealed that BmC-THF synthase gene is widely expressed in various tissues of silkworm and highly expressed in the fat body. The expression characteristics of BmC-THF synthase gene in response to oxidative stress were conducted under phoxim and high temperature (30 °C) exposure. The results showed that the transcriptional level of BmC-THF synthase gene was upregulated by 3.435-fold and 6.845-fold after phoxim and high temperature (30 °C) exposure, respectively, indicating that BmC-THF synthase gene may play a significant role in response of silkworm to oxidative stresses.
Topics: Adipose Tissue; Aminohydrolases; Animals; Bombyx; Cloning, Molecular; Formate-Tetrahydrofolate Ligase; Gene Expression Regulation, Enzymologic; Hot Temperature; Insect Proteins; Methylenetetrahydrofolate Dehydrogenase (NADP); Multienzyme Complexes; Open Reading Frames; Organothiophosphorus Compounds; Oxidative Stress; Phylogeny; Tissue Distribution
PubMed: 29660516
DOI: 10.1016/j.gene.2018.04.037 -
Archives of Insect Biochemistry and... Oct 2018The development of insecticide resistance is attributed to evolutionary changes in pest insect genomes, such as alteration of drug target sites, upregulation of...
The development of insecticide resistance is attributed to evolutionary changes in pest insect genomes, such as alteration of drug target sites, upregulation of degrading enzymes, and enhancement of drug excretion. Beyond these well-known mechanisms, symbiotic bacteria may confer insecticide resistance to host crickets. The current study was designed to screen all possible culturable bacterial groups found living in and on the bodies of Teleogryllus occipitalis crickets. We recovered 263 visible bacterial colonies and cultured them individually. After identifying the colonies based on morphology and phylogenetic analysis, we shortlisted 55 bacterial strains belonging to 28 genera. Of these 55 bacterial strains, 18 degraded at least 50% of the original amount of 400 mg/L chlorpyrifos (CP) after 24 hr of coculture. Six of these strains degraded more than 70% of the original amount of 400 mg/L CP. Three strains had antagonistic effects on Bacillus thuringiensis growth. Additionally, the ability of the isolates to degrade glyphosate, phoxim, and esfenvalerate was assessed. We also detected extracellular hydrolase enzyme activities in these isolates. We propose that epiphytic bacterial strains play multiple roles in cricket biology, one of which contributes to chemical and biological pesticide resistance.
Topics: Animals; Bacteria; China; Glycine; Gryllidae; Hydrolases; Insecticide Resistance; Insecticides; Nitriles; Organothiophosphorus Compounds; Phylogeny; Pyrethrins; RNA, Bacterial; RNA, Ribosomal, 16S; Sequence Analysis, RNA; Glyphosate
PubMed: 30120789
DOI: 10.1002/arch.21501