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1.
Environ Monit Assess ; 193(3): 129, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33587214

RESUMO

Samples of leaves, flowers, soil, pollen, bee workers, bee brood, honey, and beeswax were collected to assess the possibility of a transfer of captan, thiacloprid, penthiopyrad, and λ-cyhalothrin from apple trees of Idared variety to honey bee (Apis mellifera) hives. Chemical analyses were performed using the Agilent 7890 Gas Chromatograph equipped with the Micro-cell Electron Capture Detector. It was found that significant amounts of penthiopyrad, the active ingredient of Fontelis 200 SC, were present in leaves, flowers, pollen, bee workers, and beeswax. Simultaneously, captan was present in the brood, worker bees, and honey samples. Significant levels of the captan residues were also detected on the soil surface. In honey samples, captan residue levels exceeded the acceptable standard, reaching 160% of its maximum residue level. However, in no case the amounts of captan, thiacloprid, penthiopyrad, and λ-cyhalothrin ingested with honey by an adult consumer exceeded the level of 0.02% of the acceptable daily intake. Despite the trace amounts of pesticide residues in honey samples collected during the field trial, bee honey consumption can be considered safe. An adult consumer can safely consume about 16 kg of honey.


Assuntos
Inseticidas , Malus , Animais , Abelhas , Captana/análise , Monitoramento Ambiental , Insetos , Inseticidas/análise , Inseticidas/toxicidade , Neonicotinoides , Nitrilos , Pirazóis , Piretrinas , Tiazinas , Tiofenos
2.
J Insect Sci ; 21(1)2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33560356

RESUMO

Honey bees are important pollinators of wild plants and crops. MicroRNAs (miRNAs) are endogenous regulators of gene expression. In this study, we initially determined that the lethal concentration 50 (LC50) of dinotefuran was 0.773 mg/l. Then, the expression profiles and differentially expressed miRNAs (DE miRNAs) in honey bee brains after 1, 5, and 10 d of treatment with the lethal concentration 10 (LC10) of dinotefuran were explored via deep small-RNA sequencing and bioinformatics. In total, 2, 23, and 27 DE miRNAs were identified after persistent exposure to the LC10 of dinotefuran for 1, 5, and 10 d, respectively. Some abundant miRNAs, such as ame-miR-375-3p, ame-miR-281-5p, ame-miR-3786-3p, ame-miR-10-5p, and ame-miR-6037-3p, were extremely significantly differentially expressed. Enrichment analysis suggested that the candidate target genes of the DE miRNAs are involved in the regulation of biological processes, cellular processes, and behaviors. These results expand our understanding of the regulatory roles of miRNAs in honey bee Apis mellifera (Hymenopptera: Apidae) responses to neonicotinoid insecticides and facilitate further studies on the functions of miRNAs in honey bees.


Assuntos
Abelhas/efeitos dos fármacos , Encéfalo/metabolismo , Guanidinas/toxicidade , Inseticidas/toxicidade , MicroRNAs/genética , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Transcriptoma , Animais , Abelhas/genética , Abelhas/metabolismo , Encéfalo/efeitos dos fármacos , MicroRNAs/metabolismo
3.
Sci Total Environ ; 765: 144253, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33418333

RESUMO

Extensive application of imidacloprid (IMI) in pest control and its undesirable removal efficiency enabled it to be a critical global challenge. Low cost, efficient, sustainable and environment-friendly technologies are urgently needed to be developed to remove IMI from water. A novel adsorbent of potassium hydroxide activated magnetic microporous loofah sponge biochar (KOH+Fe/Zn-LBC) was synthesized, as well as its adsorption capacity and mechanisms for IMI were investigated in this study. KOH+Fe/Zn-LBC had the superior pore structure (surface area and pore volume) and its maximum adsorption capacity for IMI could reach 738 mg g-1 at 298 K. Kinetics, isotherms, thermodynamics and characterization analysis suggested that pore filling, hydrogen bonding and π-π conjugation were its main adsorption mechanisms. Additionally, the thermodynamic parameters described that IMI adsorption was a spontaneous, endothermic and less random process. Particularly, the magnetic separation of KOH+Fe/Zn-LBC was beneficial for its reuse. Ultrasound and ethanol co-processing could effectively regenerate the used KOH+Fe/Zn-LBC and maintain its stable sustainable adsorption capacity (99.4% of its fresh adsorption capacity after five reuse cycles). Besides, KOH+Fe/Zn-LBC exhibited a stable adsorption capacity and environmental safety in a wide pH range. Therefore, KOH+Fe/Zn-LBC has the potential to be an efficient, green and sustainable adsorbent for neonicotinoids removal.


Assuntos
Luffa , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Concentração de Íons de Hidrogênio , Hidróxidos , Cinética , Fenômenos Magnéticos , Neonicotinoides , Nitrocompostos , Compostos de Potássio , Termodinâmica , Poluentes Químicos da Água/análise
4.
Ecotoxicol Environ Saf ; 211: 111869, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33450537

RESUMO

Solitary bees are among the most important pollinators worldwide however population declines especially in croplands has been noticed. The novel pesticide sulfoxaflor is a competitive modulator of nicotinic acetylcholine receptors (nAChR) in insects. While there is evidence of a negative impact of neonicotinoids on bees of several social organization levels, our overall knowledge on the impact of sulfoxaflor on bees is poor. Here we present for the first time a study showing effects of field realistic doses of sulfoxaflor on solitary bees. Bees submitted to long term exposure of field realistic doses of sulfoxaflor (5 µg dm-3, 10 µg dm-3, 50 µg dm-3) and control were observed regarding their survival rate. Moreover, we recorded metrics related to flower visitation and flight performance. We discover that the highest field realistic dose is lethal to Osmia bicornis along five days of exposure. The effect of sulfoxaflor reduces the outcome of foraging, important features for fruit and seed production of cross-pollinated plant species. Bees exposed to pesticide visited flowers mostly walking rather than flying. Flight performance was also impaired by the pesticide.


Assuntos
Abelhas/fisiologia , Inseticidas/toxicidade , Animais , Comportamento Alimentar/efeitos dos fármacos , Flores/efeitos dos fármacos , Neonicotinoides/toxicidade , Praguicidas/toxicidade , Polinização/efeitos dos fármacos , Piridinas , Compostos de Enxofre , Taxa de Sobrevida
5.
J Insect Sci ; 21(1)2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33400795

RESUMO

Honey bees are important pollinators of wild plants and crops. MicroRNAs (miRNAs) are endogenous regulators of gene expression. In this study, we initially determined that the lethal concentration 50 (LC50) of dinotefuran was 0.773 mg/l. Then, the expression profiles and differentially expressed miRNAs (DE miRNAs) in honey bee brains after 1, 5, and 10 d of treatment with the lethal concentration 10 (LC10) of dinotefuran were explored via deep small-RNA sequencing and bioinformatics. In total, 2, 23, and 27 DE miRNAs were identified after persistent exposure to the LC10 of dinotefuran for 1, 5, and 10 d, respectively. Some abundant miRNAs, such as ame-miR-375-3p, ame-miR-281-5p, ame-miR-3786-3p, ame-miR-10-5p, and ame-miR-6037-3p, were extremely significantly differentially expressed. Enrichment analysis suggested that the candidate target genes of the DE miRNAs are involved in the regulation of biological processes, cellular processes, and behaviors. These results expand our understanding of the regulatory roles of miRNAs in honey bee Apis mellifera (Hymenopptera: Apidae) responses to neonicotinoid insecticides and facilitate further studies on the functions of miRNAs in honey bees.


Assuntos
Encéfalo/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Guanidinas/toxicidade , Inseticidas/toxicidade , MicroRNAs/metabolismo , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Animais , Abelhas , Encéfalo/metabolismo
6.
Environ Monit Assess ; 193(2): 102, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33515343

RESUMO

Imidacloprid, used against mango hopper, is a persistent insecticide in soil. Microbes have the ability to remove toxic pesticides from soil surface. Metagenomic is an approach for understanding the diversity and related metabolic activities in any environmental sample without culturing the microbes. Metagenomic analysis of mango orchard soil was carried out using 16S rRNA gene sequencing to understand the impact of imidacloprid on soil microbial population. In control and imidacloprid applied soil samples, representative sequences clustered were 0.142930 and 0.082320 million, respectively. At the kingdom level, 85 and 88 percent represented to bacteria, 2 and 1 percent to archaea, and 13 and 11 percent to unassigned for control and treated metagenomes, respectively. At phylum level, 16 and 17 percent of OTUs (operational taxonomic units) were assigned with Proteobacteria, while 13 and 11 percent of OTUs were unassigned in control and imidacloprid-treated samples, respectively. The other abundant phyla in both the samples were Planctomycetes, Bacteroidetes, and Actinobacteria. At class level, 9 and 11 percent of OTUs were assigned with Planctomycetia in control as well as imidacloprid-treated samples, respectively. A number of OTUs present in control and imidacloprid applied samples are 31,173 and 21,909, respectively, with 18,018 number of OTUs shared between the two samples. The genus Gemmata totally disappeared in imidacloprid applied soil, while those belonging to class Phycisphaerae, genus Prevotella and species copri were identified in imidacloprid treatment. Bacterial community transformation was evident from this study indicating possible microbial bioremediation of imidacloprid in mango orchard soil.


Assuntos
Mangifera , Metagenoma , Bactérias/genética , Monitoramento Ambiental , Neonicotinoides , Nitrocompostos , Filogenia , RNA Ribossômico 16S/genética , Solo , Microbiologia do Solo
7.
Sci Total Environ ; 763: 142957, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33498114

RESUMO

The aim of this study was to estimate the risk posed by imidacloprid (IMI) seed coating to passerine birds of the Pampa Region of Argentina using data specifically generated with the grayish baywing (Agelaioides badius). Median lethal dose (LD50) of the IMI-based formulation tested was 57.11 mg IMI/kg body weight (bw), with intoxication signs starting from 20.6 mg IMI/kg bw. The feed intake rate (FIR) was estimated experimentally as 4.895 g/day per bird, representing 12.43% of bw. It was calculated that the ingestion of 7-10% of the FIR as treated seeds would be enough to achieve the LD50 for sorghum, corn, sunflower, and alfalfa, whereas consumption of 31 and 54% of FIR was necessary for oat and wheat, respectively. Based on spill data values available in the literature, it was calculated that, for most crops, a baywing would have to forage an area of field corresponding to less than 60 m2 to obtain the number of seeds required to reach the LD50. It was also shown that this number of seeds is coherent with the amount of seeds ingested in a bout. In a pilot study, all grayish baywings fed with millet seeds treated with 3 g IMI/kg died within three to five days of exposure. In Tier I risk assessment, the trigger value was achieved for all crops except soybean and a weight-of-evidence risk assessment was performed. All lines of evidence examined are consistent with the view that grayish baywings, and probably other small farmland birds, are exposed to a risk of acute toxicity and mortality under both worst-case and mixed-ration exposure scenarios. The possible impacts on bird species calls for an urgent reconsideration of IMI seed coating practices currently approved in the Pampa Region of Argentina and the various parts of the world where this practice is still in use.


Assuntos
Inseticidas , Passeriformes , Animais , Argentina , Peso Corporal , Fazendas , Inseticidas/análise , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Projetos Piloto , Sementes/química
8.
Ecotoxicol Environ Saf ; 208: 111681, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396013

RESUMO

Analysis of particulate matter originating from beef cattle feed yards on the High Plains of the United States has revealed occurrence of multiple pesticides believed to potentially impact non-Apis pollinators. Among these pesticides are those that are highly toxic to Apis mellifera (honey bees). However, little non-Apis bee species toxicity data exist; especially pertaining to beef cattle feed yard-derived pesticides. Therefore, we conducted a series of 96-h contact toxicity tests with blue orchard mason bees (Osmia lignaria) using three neonicotinoids, two pyrethroids, and two macrocyclic lactones. Neonicotinoids (thiamethoxam, imidacloprid, and clothianidin) were most toxic with LD50 values ranging from 2.88 to 26.35 ng/bee, respectively. Macrocyclic lactones (abamectin and ivermectin) were also highly toxic to O. lignaria with LD50 estimates of 5.51-32.86 ng/bee. Pyrethroids (permethrin and bifenthrin) were relatively less toxic with LD50 values greater than 33 ng/bee. Sensitivity ratios for each pesticide were calculated to relate O. lignaria LD50 values to existing honey bee toxicity data. All three neonicotinoids were more toxic to O. lignaria than A. mellifera, but pyrethroids and abamectin were relatively less toxic. Additionally, three of seven pesticides (43%) resulted in significantly different mass normalized LD50 values for male and female O. lignaria. These results indicate that non-Apis pollinators may be highly susceptible to pesticides originating from beef cattle feed yards, necessitating consideration of more stringent regulatory protections than those based on A. mellifera pesticide sensitivity.


Assuntos
Abelhas/efeitos dos fármacos , Lactonas/toxicidade , Compostos Macrocíclicos/toxicidade , Neonicotinoides/toxicidade , Praguicidas/toxicidade , Piretrinas/toxicidade , Animais , Relação Dose-Resposta a Droga , Feminino , Dose Letal Mediana , Masculino , Modelos Teóricos , Polinização/efeitos dos fármacos , Testes de Toxicidade Aguda
9.
Environ Pollut ; 269: 116191, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33316505

RESUMO

Co-occurrence of pesticides and heavy metals has attracted extensive attention. The enantioselective behaviors of dinotefuran to aquatic organisms have not been reported, and the effects of cadmium (Cd) was absent, which were investigated in this study at environmentally relevant concentrations. The enantioselective accumulation and elimination of dinotefuran enantiomers were observed in zebrafish, and it had tissue specificity. The S-dinotefuran concentrations were higher than R-dinotefuran in heads and viscera, but it was opposite in muscles. There existed competition between S-dinotefuran and R-dinotefuran, and the existence of S-dinotefuran might decrease the accumulation and elimination of the R-dinotefuran in zebrafish. When co-exposure to Cd and dinotefuran, the accumulation concentrations of dinotefuran enantiomers increased in zebrafish at the initial stage, which were opposite latterly. The accumulation concentrations of R-dinotefuran in R + Cd treatment in fish were 3.4 times higher than those in R-dinotefuran treatment, and the enantiomer fraction (EF) values changed from 0.484 to 0.195. The oxidative stress of S-dinotefuran on zebrafish was highest, followed by rac- and R-dinotefuran. Co-exposure to Cd led to toxicity increase for R-dinotefuran, the malonaldehyde (MDA) content decreased significantly in R + Cd treatment during 7-28 days, while obvious declination of MDA contents was found on the 28th day in R-dinotefuran treatment. Furthermore, compared to R-dinotefuran treatment, Cd increased the relative expression of cz-sod (3.4 times), cas3 (1.6 times) and p53 (5.7 times) in R + Cd treatment. The co-exposure of Cd might alter the environmental behaviors and toxicity effects of dinotefuran enantiomers in zebrafish, including the enantioselectivity. The effects of Cd on accumulation and toxicity of R-dinotefuran were greater than those on S-dinotefuran. Thus, it is necessary to consider the effects of coexistent metals to chiral pesticides in ecological risk. SUMMARIZES: The enantioselective accumulation and elimination of dinotefuran enantiomers had tissue specificity. Cd increased the accumulation and toxicity of R-dinotefuran in zebrafish.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Bioacumulação , Cádmio/toxicidade , Guanidinas , Neonicotinoides , Nitrocompostos , Estereoisomerismo , Poluentes Químicos da Água/toxicidade
10.
Environ Pollut ; 270: 116156, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33321437

RESUMO

In developing countries, urban areas may be at greater risk of pesticide exposure compared to semi-urban agricultural regions. To investigate this, concentrations of selected pesticides were measured in 81 human milk samples collected in urban Kolkata and semi-urban Nadia in West Bengal, India. Three classes of pesticides were investigated - legacy organochlorines and emerging pyrethroids and neonicotinoids. The average concentration of the majority of the chemicals (DDT, its metabolites, HCH isomers, bifenthrin, endosulfan), showed a clear urban > semi-urban trend. Compared with previous measurements in other Indian cities and developing nations, current HCH and DDT concentrations in urban Kolkata were high. These chemicals were detected in 100% of the samples in both the urban and the semi-urban region. Also in both regions, the Estimated Daily Intake of DDTs, HCHs, aldrin, dieldrin and the pyrethroid bifenthrin for breastfed infants exceeded the Tolerable Daily Intake in a number of samples. Three pyrethroids were detected in human milk samples in India for the first time. This indicates a shift in the usage pattern of pesticides in India from organochlorines to pyrethroids. These findings may be used to drive targeted regulation of pesticides in developing countries with similar histories of pesticide use.


Assuntos
Hidrocarbonetos Clorados , Resíduos de Praguicidas , Praguicidas , Piretrinas , DDT/análise , Humanos , Hidrocarbonetos Clorados/análise , Índia , Neonicotinoides , Resíduos de Praguicidas/análise , Praguicidas/análise
11.
Sci Total Environ ; 754: 141941, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33254881

RESUMO

The global intensification of agriculture has resulted in pesticides playing an increasingly important role as anthropogenic stressors and drivers of environmental change. There is also a growing need to determine if other environmental stressors, especially those predicted to worsen with climate change, interact with pesticides to alter their effects on non-target biota. Two such stressors are increased extreme temperature events and periods of food limitation. This study is the first to investigate the combined effects of the world's most widely used insecticide, imidacloprid, with heatwaves and food limitation on a freshwater animal. A 6-week, full-factorial laboratory experiment with Deleatidium spp. mayfly nymphs was performed to investigate the potential for direct and delayed interactive effects of simulated heatwaves and starvation with chronic exposure to a field-realistic concentration of imidacloprid (0.4 µg/L). The experiment included two 6-day simulated heatwaves, one during a starvation period prior to imidacloprid addition, and one during the first 6 days of imidacloprid exposure. The simulated heatwaves alone caused such drastic negative effects on Deleatidium survival and mobility that mainly antagonistic interactions were observed with the other stressors, though delayed synergisms between imidacloprid and the second heatwave also affected mayfly mobility. Time-cumulative toxicity of imidacloprid was evident, with imidacloprid first affecting mayfly mobility after 12 days but eventually causing the strongest effects of all manipulated stressors. However, lethal effects of imidacloprid could only be detected in the absence of heatwaves and starvation, possibly as a result of selection for stronger individuals due to prior exposure to these stressors. Our findings demonstrate that heatwaves of increasing severity will critically affect sensitive freshwater organisms such as mayflies, and that the impacts of widespread pesticide use on freshwater ecosystems under global climate change cannot be ignored.


Assuntos
Ephemeroptera , Inseticidas , Poluentes Químicos da Água , Animais , Ecossistema , Humanos , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Rios , Poluentes Químicos da Água/toxicidade
12.
Food Chem ; 339: 127985, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920305

RESUMO

There is limited research focusing on the effects of human gut microbiota on the oral bioaccessibility and intestinal absorption of pesticide residues in food. In the present study, we use a modified setup of the Simulator of the Human Intestinal Microbial Ecosystem for the determination of pesticide residue bioaccessibility in Chaenomeles speciosa, and a Caco-2 cell model of human intestinal absorption. Results showed that gut microbiota played a dual role based their effects on contaminant release and metabolism in the bioaccessibility assay, and Lactobacillus plantarum was one of key bacterial species in the gut microbiota that influenced pesticide stability significantly. The addition of L. plantarum to the system reduced the relative amounts (by 11.40-86.51%) of six pesticides. The interaction between the food matrix and human gut microbiota led to different absorption rates, and the barrier effects increased with an increase in incubation time.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Praguicidas/farmacologia , Rosaceae/química , Bactérias/metabolismo , Células CACO-2 , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/microbiologia , Lactobacillus plantarum/efeitos dos fármacos , Lactobacillus plantarum/isolamento & purificação , Neonicotinoides/metabolismo , Neonicotinoides/farmacologia , Nitrocompostos/metabolismo , Nitrocompostos/farmacologia , Compostos Organotiofosforados/metabolismo , Compostos Organotiofosforados/farmacologia , Praguicidas/química , Praguicidas/metabolismo , Rosaceae/metabolismo , Tiametoxam/metabolismo , Tiametoxam/farmacologia
13.
Pest Manag Sci ; 77(1): 417-424, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32761689

RESUMO

BACKGROUND: The use of insecticidal solutions containing sodium chloride (NaCl) has been proposed as a more environmentally friendly alternative to managing stink bug infestations of Neotropical soybean fields. The potential sublethal and undesirable effects of this practice have, however, been overlooked, especially with novel insecticides. Here, we have evaluated experimentally whether the addition of NaCl (0.5% w/v) to imidacloprid-containing solutions could alter insecticide toxicity and modify the reproductive responses of the Neotropical brown stink bug Euschistus heros. RESULTS: Adding NaCl to imidacloprid solutions significantly increased imidacloprid toxicity against E. heros. The exposure to E. heros to sublethal concentrations of imidacloprid affected the insect's mating abilities in a concentration-dependent manner. The addition of NaCl to solutions containing imidacloprid at concentrations as low as 0.126 µg a.i. cm-2 (i.e. the equivalent to 3% of field rate recommendation) also impacted the sexual behavior of E. heros, reducing mating duration. NaCl-exposed stink bugs, however, exhibited higher fecundity and fertility rates than those insects that were unexposed to NaCl or those that were exposed to sublethal levels of imidacloprid only. CONCLUSIONS: The addition of low amounts of NaCl resulted in a higher toxicity of imidacloprid. This practice, however, can also lead to undesirable effects as increasing reproductive output of E. heros that can potentially compromise the management of these insect pests.


Assuntos
Heterópteros , Inseticidas , Animais , Neonicotinoides/toxicidade , Nitrocompostos , Cloreto de Sódio
14.
Chemosphere ; 263: 127561, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33296994

RESUMO

Plants and insects are parts of a complex system that involves interactions among many trophic levels, and it is important to understand the nature of such interactions. In the complex of interactions involving aphids and transgenic cotton expressing Bacillus thuringiensis, both the spraying of neonicotinoids and the occurrence of predatory coccinellids are common. However, there are gaps regarding the knowledge about possible impacts of neonicotinoids on physiological variables of the host plant and behavioural traits of the aphid (Aphis gossypii) and predator (Cycloneda sanguinea). Therefore, this study aimed to highlight the photosynthetic and electrical responses of the plant to the stress caused by the aphid attack combined with the stress generated by the use of imidacloprid in Bt and non-Bt cotton (Gossypium hirsutum L.) cultivars and to evaluate how this stress can influence the behavioural ecology of the predator and prey. Chlorophyll a fluorescence tests, dark respiration and electrophysiology on non-Bt and Bt cotton were carried out, the behaviour of the prey and predator was also evaluated with a video capture system. Our research is a study model that generates insights about possible impacts when using Imidacloprid without the occurrence of the pest on the plant, because the exposure of non-Bt and Bt cotton plants and the predator to imidacloprid unnecessarily, may result in stress on the physiology of the cotton plants and on the behaviour of the predator.


Assuntos
Afídeos , Animais , Afídeos/genética , Clorofila A , Eletrofisiologia , Fluorescência , Gossypium/genética , Insetos , Neonicotinoides , Nitrocompostos , Plantas Geneticamente Modificadas , Respiração
15.
Chemosphere ; 263: 127960, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297023

RESUMO

Thiacloprid is a neonicotinoid insecticide used to control sucking and chewing insects of fruits and vegetables. Hydrolysis, photolysis of thiacloprid in aqueous solutions, and soil degradation of three typical types of soil in China were studied. UHPLC-QTOF/MS was used to acquire high-resolution mass spectrometry information of thiacloprid's degradation products in water and soil samples, and the UNIFI platform with integrated data processing function was used to find and identify degradation products. The degradation kinetics of thiacloprid was determined. Six transformation products (M271, M287, M269, M295, M279, M267) were found after the data processing workflow in the UNIFI platform by using the raw MSE data. The structure of putative transformation products can be inferred based on the accurate mass of fragment ions and the automated spectral interpretation tools in the UNIFI platform. The structure of M271 was validated to be thiacloprid amide by comparing the ESI-MS2 fragment ions in soil samples and thiacloprid amide standard. The TrendPlot function of UNIFI was used to demonstrate the kinetics of the transformation products. Reduction, hydrolysis, oxidation are the main reactions of thiacloprid in three tested soil in China and buffer solutions. This study provided a reference for the rapid identification of the transformation products of other pesticides in specific environmental conditions.


Assuntos
Solo , Água , China , Cromatografia Líquida de Alta Pressão , Neonicotinoides , Tiazinas
16.
Chemosphere ; 263: 128245, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297192

RESUMO

Collembolans comprise one of the most abundant groups of soil invertebrates within the arthropods. The parthenogenetic species Folsomia candida (Willem, 1902) is the most well-studied representative, being used since the beginning of the 1960s as a model organism for assessing toxicity of chemicals in soil. In this paper we aimed at answering three questions by exposing four different species of springtails (F. candida, Folsomia fimetaria, Sinella curviseta and Heteromurus nitidus) to the neonicotinoids imidacloprid and thiacloprid: i) How representative as a model organism is F. candida for species of springtails that reproduce sexually? (ii) How suitable are other species of springtails to be used as model organisms for ecotoxicological testing? (iii) Is it possible to use the life history of these species to extrapolate the impact of neonicotinoids on the population level? Our results showed that F. candida is a good model organism, despite being the most sensitive species tested, when analysing both endpoints - survival and reproduction. The tests performed with S. curviseta and H. nitidus showed that they could be used as surrogates in ecotoxicity tests, and also to predict how their population might be affected after being exposed to chemicals. The adjustments made to the test performed with F. candida: introducing adults (20-22 days old) into the test jars and exposing them for 21 days instead of 28 days, proved to be as efficient as the standardized test guideline (OECD 232, 2009).


Assuntos
Artrópodes , Poluentes do Solo , Animais , Invertebrados , Neonicotinoides/toxicidade , Reprodução , Solo , Poluentes do Solo/toxicidade
17.
Chemosphere ; 263: 128269, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297213

RESUMO

Increasing evidence indicates that insect resistance to synthesized insecticides is regulated by the nuclear receptors. However, the underlying mechanisms of this regulation are not clear. Here, we demonstrate that inhibition of hepatocyte nuclear factor 4 (HNF4) confers imidacloprid resistance in the brown planthopper (BPH) Nilaparvata lugens by regulating cytochrome P450 and UDP-glycosyltransferase (UGT) genes. An imidacloprid-resistant strain (Res) exhibited a 251.69-fold resistance to imidacloprid in comparison to the susceptible counterpart (Sus) was obtained by successive selection with imidacloprid. The expression level of HNF4 in the Res strain was lower than that in Sus, and knockdown of HNF4 by RNA interference significantly enhanced the resistance of BPH to imidacloprid. Comparative transcriptomic analysis identified 1400 differentially expressed genes (DEGs) in the HNF4-silenced BPHs compared to controls. Functional enrichment analysis showed that cytochrome P450- and UGT-mediated metabolic detoxification pathways were enriched by the up-regulated DEGs after HNF4 knockdown. Among of them, UGT-1-7, UGT-2B10 and CYP6ER1 were found to be over-expressed in the Res strain, and knockdown of either gene significantly decreased the resistance of BPH to imidacloprid. This study increases our understanding of molecular mechanisms involved in the regulation of insecticide resistance and also provides potential targets for pest management.


Assuntos
Hemípteros , Inseticidas , Animais , Sistema Enzimático do Citocromo P-450/genética , Glicosiltransferases/genética , Hemípteros/genética , Fator 4 Nuclear de Hepatócito , Imidazóis , Resistência a Inseticidas/genética , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Difosfato de Uridina
18.
Chemosphere ; 263: 128293, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297235

RESUMO

Deltamethrin (DEL) and thiacloprid (THIA) are commonly used insecticides applied either separately or as a mixture. We aimed to investigate the effects of DEL and THIA on cell viability, proliferation and DNA damage in human bronchial epithelial cells (BEAS-2B) because their effects in lung cells are not known. Our results indicate that all concentrations of DEL and THIA statistically decreased colony formation, plating efficiency and survival fraction in a concentration-dependent manner in BEAS-2B cells expect the lowest concentration for 24 h. MTT assay showed that treatment of DEL + THIA increased the cytotoxicity at higher concentrations. DEL + THIA significantly induced the foci formation of phosphorylated H2AX protein and p53 binding protein 1 at the highest concentration (44 µM DEL+666 µM THIA) for 120 h. Because gH2AX foci number was still higher in the recovery group given an additional 24 h after 120 h, the recovery period was not sufficient for DNA double-strand breaks repair.


Assuntos
Dano ao DNA , Células Epiteliais , Sobrevivência Celular , DNA , Humanos , Neonicotinoides , Nitrilos , Piretrinas , Tiazinas
19.
Pestic Biochem Physiol ; 171: 104729, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33357551

RESUMO

The melon aphid, Aphis gossypii is a globally distributed crop pest with a wide host range. The intensive use of insecticides against this insect over several years has led to develop resistance against many insecticides including acetamiprid. Understanding the relationship between acetamiprid resistance and fitness of A. gossypii is essential to limit the spread of the resistant population in the field. In this study, age-stage, two-sex life table approach was used to investigate these relationships in the lab. Results showed that resistant strain (Ace-R) had a reduced fitness (relative fitness = 0.909) along with significantly decreased adult longevity, fecundity, net reproductive (R0), mean generation time (T) and gross reproductive rate (GRR). Compared to the susceptible strain (Ace-S), the pre-adult period and total pre-oviposition period (TPOP) were also significantly shorter in Ace-R strain. Moreover, the expression profiles of EcR, JHBP, JHAMT, JHEH, USP and Vg genes supposed to be involved in insect reproduction and development were analyzed using Quantitative Real Time PCR. The EcR, JHBP, JHAMT and USP genes were up-regulated, Vg gene was down-regulated while the mRNA level of JHEH gene was statistically same in the Ace-R strain compared to the Ace-S strain. Collectively, this study provides the occurrence and magnitude of fitness costs of A. gossypii against acetamiprid resistance and could be helpful to manage the resistance evolution in field populations.


Assuntos
Afídeos , Cucurbitaceae , Inseticidas , Animais , Afídeos/genética , Feminino , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Tábuas de Vida , Neonicotinoides
20.
Pestic Biochem Physiol ; 171: 104741, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33357563

RESUMO

Insecticide resistance in pest populations is an increasing problem in both urban and rural settings due to over-application of insecticides and lack of rotation among insecticidal chemical classes. The house fly (Musca domestica L.) is a cosmopolitan pest fly species implicated in the transmission of numerous pathogens. The evolution of insecticide resistance long has been documented in house flies, with resistance reported to all major insecticide classes. House fly resistance to imidacloprid, the most widely used neonicotinoid insecticide available for fly control, has evolved in field populations through both physiological and behavioral mechanisms. Previous studies have characterized and mapped the genetic changes that confer physiological resistance to imidacloprid, but no study have examined the genetics involved in behavioral resistance to imidacloprid to date. In the current study, several approaches were utilized to characterize the genetics and inheritance of behavioral resistance to imidacloprid in the house fly. These include behavioral observation analyses, preference assays, and the use of genetic techniques for the identification of house fly chromosome(s) carrying factors. Behavioral resistance was mapped to autosomes 1 and 4. Inheritance of resistance was shown to be neither fully dominant nor recessive. Factors on autosomes 1 and 4 independently conferred contact-dependent avoidance of imidacloprid and a feeding preference for sugar alone or for sugar with dinotefuran, another neonicotinoid insecticide, over imidacloprid. This study serves as the first linkage analysis of a behavioral trait in the house fly, and provides new avenues for research regarding inherited behavior in the house fly and other animals.


Assuntos
Moscas Domésticas , Inseticidas , Animais , Moscas Domésticas/genética , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Neonicotinoides/farmacologia , Nitrocompostos
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