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1.
Molecules ; 27(19)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36235002

RESUMO

Despite an outstanding agent for control of Lepidoptera, the diamide insecticide cyclaniliprole (CYCP) is a suspected carcinogen. In the present study, an analytical method was developed for the determination of CYCP in six fruits and vegetables (apple, grape, peach, bell pepper, lettuce, and tomato) using ultrahigh-performance liquid chromatography coupled with tandem mass spectrometry. Sample preparation was carried out by the acetonitrile-salting-out extraction followed by simple and fast cleanup of disposable pipette extraction tip containing styrene divinyl benzene and/or graphitized carbon black. Satisfactory linearity (r > 0.99) was obtained in the calibration range of 0.001−1 µg mL−1. Matrix effects decreased from −9.9−−17.9% to −1.0−−7.6% after the cleanup. The recoveries of CYCP at three spike levels (0.01, 0.1, and 1 mg kg−1) from different matrices were between 75.7% and 111.5%, with the intra-day (n = 5) and inter-day (n = 15) relative standard deviations lower than 12.1%. The limit of quantification was 0.01 mg kg−1. The developed method provides a good reference for routine monitoring of CYCP in these fruits and vegetables.


Assuntos
Inseticidas , Resíduos de Praguicidas , Acetonitrilas/análise , Carcinógenos/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Diamida , Frutas/química , Inseticidas/química , Resíduos de Praguicidas/análise , Fuligem , Estirenos , Espectrometria de Massas em Tandem/métodos , Verduras/química
2.
Pestic Biochem Physiol ; 178: 104921, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34446197

RESUMO

Ryanodine receptors (RyRs) are the targets of diamide insecticides, which have been identified and characterized in a dozen insect pests of Lepidoptera, Hemiptera, Diptera and Coleoptera, but limited attention has been paid to the RyR in parasitoid natural enemies. Without this knowledge, it will hinder our effective and efficient application using both parasitoid natural enemies and diamide insecticides simultaneously in the integrated pest management (IPM). In this study, the full-length cDNA of RyR was cloned from Encarsia formosa (EfRyR), a parasitic wasp used worldwide for the biological control of whitefly. Its expression profile was examined in various tissues of E. formosa adults. The toxicities of four diamide insecticides to E. formosa were measured, and then the expression profile of EfRyR after 12 h and 24 h exposure to the LC50 dosages of diamide insecticides was investigated. The results showed that the full-length cDNA of EfRyR was 16, 778 bp including a 15, 345 bp open reading frame, and two alternative splice (AS) sites. Comparing to its expression in the abdomen, EfRyR was highly expressed in the head (11.9-fold) and the thorax (3.7-fold). The toxicities of four dimide insecticides against E. formosa from low to high were chlorantraniliprole (LC50 = 367.84 mg L-1), cyantraniliprole (221.72 mg L-1), cyclaniliprole (51.77 mg L-1), and tetrachlorantraniliprole (8.35 mg L-1). The expressions of EfRyR and its variants with AS were significantly increased after E. formosa adults were exposed to different diamide insecticides. This study improves our understanding of the RyR in parasitoid wasps and provides useful information on IPM by using E. formosa.


Assuntos
Diamida , Inseticidas , Animais , Diamida/toxicidade , Inseticidas/toxicidade , Rianodina , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Taiwan
3.
Ecotoxicol Environ Saf ; 203: 110947, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32678751

RESUMO

Cyantraniliprole was recently registered for controlling the coffee berry borer Hypothenemus hampei, the main coffee pest in the world. In this study, baseline determination and resistance monitoring to cyantraniliprole were carried out in Brazilian populations of H. hampei. Evaluations were carried out for three years with representative field-collected populations from nine coffee-producing states in Brazil, using artificial diet containing the insecticide. The likelihood of control failure due to cyantraniliprole resistance was also determined. Populations from Campo do Meio, Linhares and Jaú were more susceptible (<2-fold resistance) to cyantraniliprole than populations from Patrocínio and Londrina (17-fold). Nonetheless, the frequency of cyantraniliprole resistance insects was low and not significant throughout the regions survey and the likelihood of control failure was negligible. Therefore, cyantraniliprole remains an important management tool against the coffee berry borer without current problems of control failure. However, enough field variation in susceptibility to cyantraniliprole exists justifying attention and careful management of this insecticide to prevent quick development of insecticide resistance in populations of this insect pest species.


Assuntos
Coffea/parasitologia , Controle de Insetos/métodos , Resistência a Inseticidas , Inseticidas/farmacologia , Pirazóis/farmacologia , Gorgulhos/efeitos dos fármacos , ortoaminobenzoatos/farmacologia , Animais , Brasil , Coffea/crescimento & desenvolvimento , Probabilidade , Inquéritos e Questionários
4.
J Econ Entomol ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748560

RESUMO

Bemisia tabaci Middle East-Asia Minor 1 (MEAM1) is a significant pest that damages a wide range of high-value vegetable crops in south Florida. This pest has demonstrated the ability to develop resistance to various insecticide groups worldwide. Monitoring the resistance levels of MEAM1 populations and maintaining baseline susceptibility data are crucial for the long-term effectiveness of insecticide management strategies. We conducted serial dilution bioassays on 15 field populations of MEAM1 collected in south Florida to assess their resistance to 4 key insecticides: afidopyropen, cyantraniliprole, dinotefuran, and flupyradifurone. To quantify resistance levels, resistance ratios (RR) were generated by comparing the LC50 values of field populations to those of a known susceptible MEAM1 colony reared in the laboratory. Our findings reveal that all field-collected populations were susceptible to dinotefuran (RR 1-8) and flupyradifurone (RR 2-8). While over 80% of the populations tested were susceptible to afidopyropen (RR 1-9), 2 populations exhibited low (RR 38) and moderate resistance (RR 51), respectively. In contrast, most of the populations (57%) showed low to moderate resistance to cyantraniliprole (RR 21-78), and the remaining populations were susceptible (RR 3-10). The 2 populations with resistance to afidopyropen also exhibited moderate resistance to cyantraniliprole. Further research in this direction can aid in refining insecticide resistance management programs in Florida and other regions where B. tabaci MEAM1 is a major pest. Exploring the implications of these findings will be essential for insecticide use and integrated pest management strategies in south Florida.

5.
Insects ; 15(6)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38921165

RESUMO

Cyantraniliprole is a novel anthranilic diamide insecticide registered for controlling chewing and sucking insect pests. Here, the lethal and sublethal effects of this insecticide on two destructive lepidopteran pests, Spodoptera littoralis Boisduval and Agrotis ipsilon Hufnagel, were evaluated. Because the effects of novel insecticides on beneficial and non-target arthropods must be considered, the impact of cyantraniliprole on a generalist biological control agent, Chrysoperla carnea [Stephens 1836], were also examined. Overall, our study revealed that cyantraniliprole was more toxic to A. ipsilon than to S. littoralis. Moreover, the LC15 and LC50 of the insecticide significantly prolonged the duration of the larval and pupal stages and induced enzymatic detoxification activity in both species. Treatment of the second-instar larvae of C. carnea with the recommended concentration of cyantraniliprole (0.75 mg/L) doubled the mortality rates and resulted in a slight negative effect on the biology and detoxification enzymes of C. carnea. Our results indicate that both sublethal and lethal concentrations of cyantraniliprole can successfully suppress S. littoralis and A. ipsilon populations. They also suggest that C. carnea, as a generalist predator, is compatible with cyantraniliprole under the modelled realistic field conditions. In future investigations, insights into the effects of cyantraniliprole on S. littoralis, A. ipsilon, and C. carnea under field conditions will be required to appropriately validate our results.

6.
J Agric Food Chem ; 71(29): 11001-11007, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37462137

RESUMO

Ryanodine receptor (RyR) has been used as an insecticide target to control many destructive agricultural pests. The effectiveness of these insecticides has been limited by the spread of resistance mutations identified in pest RyRs, but the detailed molecular impacts of the individual mutations on the activity of different diamide compounds have not been fully explored. We created five HEK293 cell lines stably expressing wild type rabbit RyR1, wild type Spodoptera frugiperda RyR (Sf RyR), or Sf RyR carrying different resistance mutations, including G4891E, G4891E/I4734M, and Y4867F, respectively. R-CEPIA1er, a genetically encoded fluorescent protein, was also introduced in these cell lines to report the Ca2+ concentration in the endoplasmic reticulum. We systematically characterized the activities of six commercial diamide insecticides against different RyRs using the time-lapse fluorescence assay. Among them, cyantraniliprole (CYAN) displayed the highest activity against all three resistant Sf RyRs. The good performance of CYAN was confirmed by the toxicity assay using gene-edited Drosophila expressing the mutant RyRs, in which CYAN showed the lowest LD50 value for the double resistant mutant. In addition, we compared their acitivty between mammalian and insect RyRs and found that flubendiamide has the best insect-selectivity. The mechanism of the anti-resistance property and selectivity of the compounds was proposed based on the structural models generated by homology modeling and molecular docking. Our findings provide insights into the mechanism of insect resistance and guidance for developing effective RyR agonists that can selectively target resistant pests.


Assuntos
Inseticidas , Mariposas , Humanos , Animais , Coelhos , Inseticidas/farmacologia , Inseticidas/química , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Diamida/farmacologia , Simulação de Acoplamento Molecular , Células HEK293 , Resistência a Inseticidas/genética , Mariposas/genética , Mariposas/metabolismo , Mamíferos/metabolismo
7.
Environ Int ; 179: 108185, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37688810

RESUMO

As a representative variety of diamide insecticides, cyantraniliprole has broad application prospects. In this study, the fate and risk of cyantraniliprole and its main metabolite J9Z38 in a water-sediment system were investigated. The present result showed that more J9Z38 was adsorbed in the sediment at the end of exposure. However, the bioaccumulation capacity of cyantraniliprole in zebrafish was higher than that of J9Z38. Cyantraniliprole had stronger influence on the antioxidant system and detoxification system of zebrafish than J9Z38. Moreover, cyantraniliprole induced more significant oxidative stress effect and more differentially expressed genes (DEGs) in zebrafish. Cyantraniliprole had significantly influence on the expression of RyR-receptor-related genes, which was confirmed by resolving their binding modes with key receptor proteins using AlphaFold2 and molecular docking techniques. In the sediment, both cyantraniliprole and J9Z38 had inhibitory effects on microbial community structure diversity and metabolic function, especially cyantraniliprole. The methane metabolism pathway, mediated by methanogens such as Methanolinea, Methanoregula, and Methanosaeta, may be the main pathway of degradation of cyantraniliprole and J9Z38 in sediments. The present results demonstrated that metabolism can reduce the environmental risk of cyantraniliprole in water-sediment system to a certain extent.


Assuntos
Água , Peixe-Zebra , Animais , Simulação de Acoplamento Molecular , Bioacumulação
8.
J Econ Entomol ; 116(6): 1998-2008, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-37942675

RESUMO

Wireworms are primary pests of potatoes in Canada with relatively few effective control options. Recently, a new meta-diamide insecticide, broflanilide, was registered in Canada and the United States as an in-furrow spray applied at planting that provides protection of tubers from feeding damage and dramatically reduces wireworm populations. As part of our routine screening of wireworm response to novel insecticides, we exposed wireworms (predominantly Agriotes obscurus; N=2320) to field soil collected from plots to which either bifenthrin (Capture 2EC) or broflanilide (Cimegra) had been applied at registered rates 124-145 and 314-335 days previously in 2018, 2019, and 2021. Wireworm behavioral responses were assessed using a previously developed numerical scale, and indicated residues were present in sufficient quantity in all broflanilide and most bifenthrin-treated plots to induce morbidity. Transfer of affected wireworms to untreated soil indicated morbidity was generally reversible after exposure to bifenthrin, but not after exposure to broflanilide. There was an inverse relation between wireworm size and the degree of morbidity induced by exposure to broflanilide, but not bifenthrin. Analyses of soil residues indicated readily quantifiable levels of broflanilide still present in undisturbed (not harvested) field soil 314-335 days after application. Insecticide residues in soil samples from disturbed (harvested) sections of the potato plots were lower, as was the degree of morbidity of wireworms exposed to this soil. The use of wireworms as bioindicators of insecticide residues, and the implications of insecticide persistence for wireworm management are discussed.


Assuntos
Besouros , Inseticidas , Solanum tuberosum , Animais , Inseticidas/farmacologia , Solo , Larva
9.
J Agric Food Chem ; 71(46): 17646-17657, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37939255

RESUMO

Diamide insecticides have gained popularity due to their high efficacy and low toxicity to nontarget organisms. However, diamide-associated resistance has emerged recently, causing a significant reduction in their potency, thereby hindering sustainable agricultural development. Here, we explored novel diamide insecticide analogs and, using a structure-based approach, rationally designed and synthesized 28 nitrophenyl substituted anthranilic diamides. Most of the compounds showed moderate to good activity against Mythimna separata, Plutella xylostella, and Spodoptera frugiperda. Among them, compounds Ia and Im showed extraordinarily high activity and their mode of action was verified on isolated neurons. Additionally, Im exhibited over 10-fold greater potency than chlorantraniliprole in a HEK293 cell line stably expressing S. frugiperda ryanodine receptors (SfRyRs) containing the resistance mutations, G4891E and I4734M. The binding modes of Im in the SfRyRs were predicted using in silico molecular docking analysis. Our novel nitrophenyl substituted anthranilic diamide derivatives provide valuable insights for the design of insecticidal RyR-targeting compounds to effectively control both wild type and diamide insecticide-resistant lepidopteran pests.


Assuntos
Inseticidas , Mariposas , Animais , Humanos , Diamida/farmacologia , Simulação de Acoplamento Molecular , Células HEK293 , Mariposas/genética , Spodoptera/metabolismo , Inseticidas/farmacologia , Inseticidas/química , ortoaminobenzoatos/farmacologia , ortoaminobenzoatos/química , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Resistência a Inseticidas/genética
10.
J Agric Food Chem ; 71(47): 18188-18196, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37191337

RESUMO

Silicon-containing compounds are sporadically used in crop protection and drug discovery and have demonstrated to increase the biological efficacy as well as to reduce toxicity, improve physicochemical properties, and favorably impact the environmental profile. As part of our research, we have investigated the application of bioisosteric silicon replacements in meta-diamide insecticides and studied the biological activity and molecular properties of the corresponding novel compounds. At all meaningful structural elements of the meta-diamides, silicon-containing substituents were introduced and synthetic methodology was developed for their syntheses. As the most promising compound, silicon-containing meta-diamide II-18 emerged, which exhibits a very low LC50 value of 2.00 mg/L against Mythimna separata and compares well to the reference compounds 28 (LC50 = 0.17 mg/L) and II-20 (LC50 = 0.27 mg/L). Our research on silicon-containing crop protection compounds once again confirmed that the biological activity can be beneficially affected by the insertion of silicone substituents and that the introduction of well-chosen silicone motifs is an excellent strategy for agrochemical research.


Assuntos
Inseticidas , Mariposas , Animais , Inseticidas/química , Relação Estrutura-Atividade , Diamida/química , Silício/farmacologia , Compostos de Silício , Silicones
11.
J Agric Food Chem ; 71(39): 14137-14150, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37733789

RESUMO

The research and development of organofluorine chemistry has flourished; in particular, monofluoroalkene has aroused considerable interest from medicinal and organic chemists. It is a significant attempt to introduce monofluoroalkene into agrochemicals. In this study, monofluoroalkene was introduced into diamide molecules and inserted between the aliphatic amide and benzene ring, and 44 compounds have been successfully synthesized. The bioassay results showed that compounds with monofluoro-acrylamide moiety (Z-isomers) had excellent larvicidal activity against lepidopteran pests at 5 mg·L-1. The LC50 values of compounds B16, B18, and B21 against Mythimna separata were 1.02, 1.32, and 0.78 mg·L-1, respectively. 3D-QSAR analysis including the CoMFA model and the CoMSIA model was conducted to illustrate the contributions of steric, electrostatic, hydrophobic, and hydrogen bond fields on the bioactivity. Moreover, typical symptoms caused by chlorantraniliprole including dehydration, shrinkage, and blackening were also observed on the test larvae treated with monofluoro-acrylamide diamide compounds. M. separata central neurons calcium imaging experiment of compound B18 indicated that the monofluoro-acrylamide diamide compounds were potential insect ryanodine receptor activators. The molecular docking was performed in the CHL binding domain of Plutella xylostella RyR and revealed that the predicted binding mode of compound B21 was slightly different from that of CHL. The MM|GBSA dG Bind values of B21 and CHL with P. xylostella RyR were respectively -85.797 and -95.641 kcal·mol-1. The present work explored the insecticidal properties of a new diamide scaffold containing a monofluoro-acrylamide fragment and extended the application of monofluoroalkene in the agrochemical field.


Assuntos
Inseticidas , Mariposas , Animais , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Diamida/farmacologia , Diamida/química , Acrilamidas , Simulação de Acoplamento Molecular , Mariposas/metabolismo , Inseticidas/farmacologia , Inseticidas/química , Acrilamida , ortoaminobenzoatos/química
12.
Sci Total Environ ; 836: 155448, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-35508239

RESUMO

In the present study, aqueous behavior and fate of diamide insecticide tetrachlorantraniliprole (TCTP) were investigated under laboratory-controlled conditions. Half-lives of TCTP photolysis in natural water and pH buffers were 1.4-2.8 h, comparing with those of 1.2-231 d for hydrolysis. Both processes were highly influenced by pH with respect to degradation kinetics and routes. The hydrolysis rate of TCTP was accelerated by elevated temperatures. The presence of nitrate enhanced TCTP photolysis while fulvic acid exhibited suppression, with the extent of both effects as a function of concentration. Four degradation products were identified using a variety of spectroscopic approaches. Key reactions involved in the degradation pathways include intramolecular substitution and cyclization. There was a reduction in the acute toxicity of all four products to Daphnia magna by comparison with TCTP, whereas they were still classified as category 1 or 2 hazardous substances to the aquatic environment according to the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) standards.


Assuntos
Inseticidas , Poluentes Químicos da Água , Diamida , Inseticidas/toxicidade , Cinética , Fotólise , Água/química , Poluentes Químicos da Água/análise
13.
J Econ Entomol ; 115(6): 1930-1946, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36222544

RESUMO

Wireworms are primary pests of potatoes in Canada. Presently, the highly toxic organophosphate phorate (i.e., Thimet 20G) is the only effective insecticide in use in Canada. As such, there is an urgent need for novel alternative treatments that provide competitive tuber blemish protection and wireworm reduction with a safer human and environmental portfolio. Herein we evaluated broflanilide, a novel meta-diamide insecticide for both tuber protection and wireworm mortality. When evaluated in field trials in Agassiz, British Columbia over 6 yr, broflanilide applied as a seed piece treatment (SPT) to mother tubers at 1.5-2.0 g AI/100 kg seed (approx. 50 g AI/ha), or as an in-furrow spray (IFS) at 0.23-0.25 g AI/100 m row (approx. 25 g AI/ha) was as effective at reducing blemishes to daughter tubers by wireworms (Agriotes obscurus) as phorate (Thimet 20G at 3230 g AI/ha), bifenthrin (Capture 2EC IFS at 300 g AI/ha) and clothianidin (Titan ST at 312.5 g AI/ha). In addition, broflanilide SPT and IFS applied at the above rates reduced resident wireworms (in the field at the time of planting) by 95.4-99.0% and neonate wireworms (produced from eggs laid during the growing season) by 98.1-100%. Similar results were obtained when broflanilide IFS (nonsystemic) was paired with clothianidin SPT (systemic) for broad-spectrum potato insect pest control. Strategies for the use of broflanilide on wheat (e.g., Teraxxa F4) in rotation with potatoes (Cimegra), both registered in Canada in 2020 are discussed.


Assuntos
Besouros , Inseticidas , Solanum tuberosum , Humanos , Animais , Diamida , Forato , Colúmbia Britânica
14.
J Agric Food Chem ; 70(39): 12398-12407, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36154000

RESUMO

Bemisia tabaci is an important agricultural sucking pest, and it develops serious resistance to various insecticides. Although cytochrome P450 was involved in the resistance to cyantraniliprole, limited studies have been conducted on B. tabaci. In the present study, piperonyl butoxide significantly increased the toxicity of cyantraniliprole. P450 activities in two resistant populations were 1.97- and 2.17-fold higher than that in the susceptible population. Among 79 P450 genes, CYP6CX3 expressions in two resistant populations were 3.08- and 3.67-fold higher than that in the susceptible population. When CYP6CX3 was knocked down, the toxicity of cyantraniliprole increased significantly. The LC50 value of cyantraniliprole to the Drosophila melanogaster line overexpressing B. tabaci CYP6CX3 increased 7.34-fold. The content of cyantraniliprole was decreased by 25.74 ± 4.27% after mixing with CYP6CX3 and CPR for 2 h. These results suggested that the overexpression of CYP6CX3 was likely involved in the resistance to cyantraniliprole in B. tabaci.


Assuntos
Hemípteros , Inseticidas , Animais , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Drosophila melanogaster , Resistência a Inseticidas/genética , Inseticidas/metabolismo , Inseticidas/farmacologia , Butóxido de Piperonila/metabolismo , Pirazóis , ortoaminobenzoatos
15.
Front Physiol ; 13: 1107045, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36620218

RESUMO

In recent years, the leaf beetle Galeruca daurica has broken out in the northern grasslands of Inner Mongolia, its management still mainly depends on chemical control using traditional insecticides or with novel action. The study was aim to identify mutation locus associated with resistance to diamide insecticides in field population of G. daurica, to provide a reference for rational selection of insecticides and to avoid the rapid resistance development to diamide insecticides. We cloned the full length of the ryanodine receptor gene of G. daurica (GdRyR), constructed 3D model and transmembrane regions by homologous modeling based on deduced amino acid sequence. Two potential mutation loci (Gly4911Glu and Ile4754Met) and allelic mutation frequencies were detected in individuals of G. daurica. In addition, their binding patterns to two diamide insecticides (chlorantraniliprole, cyantraniliprole) were analyzed separately using a molecular docking method. The full-length cDNA sequence of GdRyR (GenBank accession number: OP828593) was obtained by splicing and assembling, which is 15,399 bp in length and encodes 5,133 amino acids. The amino acid similarity of GdRyR with that of other Coleopteran insects were 86.70%-91.33%, which possessed the typical structural characteristics. An individual resistance allelic mutation frequency test on fifty field leaf beetles has identified 12% and 32% heterozygous individuals at two potential mutation loci Gly4911Glu and Ile4754Met, respectively. The affinity of the I4754M mutant model of GdRyR for chlorantraniliprole and cyantraniliprole was not significantly different from that of the wild type, and all had non-covalent interactions such as hydrogen bonding, hydrophobic interactions and π-cation interactions. However, the G4911E mutant model showed reduced affinity and reduced mode of action with two diamide insecticides, thus affecting the binding stability of the ryanodine receptor to the diamide insecticides. In conclusion, the G4911E mutation in GdRyR may be a potential mechanism for the development of resistance to diamide insecticides on G. daurica and should be a key concern for resistance risk assessment and reasonable applications of diamide insecticides for control in future. Moreover, this study could provide a reference for ryanodine receptor structure-based insecticides design.

16.
Insects ; 13(10)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36292908

RESUMO

Insecticides used in agricultural pest management pose survival risks to the stingless bees that forage on crops in tropical and subtropical regions. In the present study, we evaluated, under laboratory conditions, the acute oral toxicity of five selected insecticides (dinotefuran, imidacloprid, flupyradifurone, spirotetramat, and cyantraniliprole) to two species of neotropical stingless bees: Nannotrigona perilampoides and Frieseomelitta nigra. At field recommended doses, dinotefuran, imidacloprid, and flupyradifurone caused the highest mortality in both bee species. These insecticides also caused the largest decrease in the survival rate when exposed to a 10-fold dilution of the field recommended doses. Notably, dinotefuran exerted a high effect even at 100-fold dilution (100% mortality). In contrast, cyantraniliprole had a low effect and spirotetramat was virtually nontoxic. These results suggest that some insecticides used to control sap-sucking insects may have a significant negative impact on the communities of stingless bees.

17.
Insects ; 13(7)2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35886802

RESUMO

Fall armyworm (FAW), Spodoptera frugiperda, is an important lepidopteran pest in the Americas, and recently invaded the Eastern Hemisphere. In Brazil, FAW is considered the most destructive pest of corn and cotton. FAW has evolved resistance to many insecticides and Bacillus thuringiensis (Bt) proteins. Here, a large-scale monitoring was performed between 2019 and 2021 to assess diamide insecticide susceptibility in more than 65 FAW populations sampled in corn and cotton. We did not detect a significant shift in FAW susceptibility to flubendiamide, but a few populations were less affected by a discriminating rate. F2 screen results of 31 selected FAW populations across regions confirmed that the frequency of diamide resistance alleles remained rather stable. Two laboratory-selected strains exhibited high resistance ratios against flubendiamide, and cross-resistance to anthranilic diamides. Reciprocal crosses indicated that resistance is autosomal and (incompletely) recessive in both strains. F1 backcrosses suggested monogenic resistance, supported by the identification of an I4734M/K target-site mutation in the ryanodine receptor (RyR). Subsequent genotyping of field-collected samples employing a TaqMan-based allelic discrimination assay, revealed a low frequency of RyR I4790M/K mutations significantly correlated with phenotypic diamide resistance. Our findings will help to sustainably employ diamides in FAW resistance management strategies across crops.

18.
Food Chem ; 333: 127468, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32659669

RESUMO

In this study, a new method for simultaneous determination of cyantraniliprole, chlorantraniliprole, tetrachlorantraniliprole, cyclaniliprole and flubendiamide in edible mushrooms by high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) combined with a modified QuEChERS procedure. The samples were extracted using acetonitrile and then cleaned up by primary secondary amine (PSA) and octadecylsilane (C18). The determination of these insecticides was achieved in less than 5 min using an electrospray ionization source in positive mode (ESI+) for cyantraniliprole and chlorantraniliprole, while negative mode (ESI-) for tetrachlorantraniliprole, cyclaniliprole and flubendiamide. The linearities of the calibrations for all target compounds were acceptable (R2 ≥ 0.9922). The limits of detection and quantification were 0.05-2 µg kg-1 and 5 µg kg-1, respectively. Acceptable recoveries (73.5-110.2%) were acquired for these insecticides with RSDs less than 12.7%. The results demonstrated that the proposed method was effective and convenient for the determination of these insecticides in edible mushrooms.


Assuntos
Agaricales/química , Diamida/análise , Análise de Alimentos/métodos , Inseticidas/análise , Espectrometria de Massas em Tandem/métodos , Benzamidas/análise , Cromatografia Líquida de Alta Pressão/métodos , Diamida/análogos & derivados , Pirazóis/análise , Sulfonas/análise , ortoaminobenzoatos/análise
19.
Chemosphere ; 249: 126479, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32208218

RESUMO

As part of a new generation of diamide insecticides, cyantraniliprole has broad application prospects. In the present study, a QuEChERS-UPLC-MS/MS method was established to determine the residues of cyantraniliprole and its main metabolite J9Z38 in soil and earthworms. Moreover, the accumulation and toxicity of cyantraniliprole and J9Z38 in earthworms were evaluated. The present results show that the detection method of cyantraniliprole and J9Z38 has high sensitivity and accuracy, which could be used for the accurate quantification of cyantraniliprole and J9Z38 residues in soil and earthworms. Additionally, cyantraniliprole degraded faster than its main metabolite J9Z38 in the artificial soil. Moreover, the bioenrichment efficiency of cyantraniliprole was higher than J9Z38. The toxicity test result showed that cyantraniliprole and J9Z38 could induce oxidative stress effect in earthworms from 5.0 mg/kg, finally resulting in cellular damage. Moreover, the oxidative damage degree induced by cyantraniliprole was higher than J9Z38. Combining the results of residue test and toxicity test, although cyantraniliprole degraded faster than its main metabolite J9Z38 in the artificial soil, its risk to earthworms was higher than J9Z38.


Assuntos
Inseticidas/toxicidade , Resíduos de Praguicidas/toxicidade , Pirazóis/toxicidade , ortoaminobenzoatos/toxicidade , Animais , Cromatografia Líquida , Diamida , Inseticidas/análise , Oligoquetos/efeitos dos fármacos , Resíduos de Praguicidas/análise , Pirazóis/análise , Solo/química , Poluentes do Solo/análise , Espectrometria de Massas em Tandem/métodos , Testes de Toxicidade , ortoaminobenzoatos/análise
20.
Pest Manag Sci ; 76(8): 2582-2588, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32237052

RESUMO

BACKGROUND: The loss of honey bee colonies is a nationally recognized problem that demands attention from both the scientific community and the beekeeping industry. One outstanding threat is the unintended exposure of these pollinators to agricultural pesticides. Anthranilic diamides, such as chlorantraniliprole, are registered for use in stone and pome fruits, vegetables, turf, and grains. There are few publicly available studies that provide an analysis of chlorantraniliprole effects on the survivorship and locomotion activity of beneficial, pollinating insects such as honey bees. The data gathered in this study provide the acute toxicity, 30-day survivorship, and locomotor activity of honey bees exposed to technical-grade chlorantraniliprole and three formulated products with chlorantraniliprole as the active ingredient. RESULTS: Neither the technical-grade nor the formulated products of chlorantraniliprole were acutely toxic to honey bees following 4 or 72h treatments at the tested concentrations. A 4 h treatment of technical-grade and formulated chlorantraniliprole did not significantly affect the 30-day survivorship, although significantly higher mortality was observed after 30 days for bees receiving a 72 h treatment of technical-grade chlorantraniliprole and two formulated products. The locomotion activity, or total walking distance, of bees receiving a 4 h treatment of one chlorantraniliprole formulation was significantly reduced, with these individuals recovering their normal locomotion activity at 48 h post exposure. Conversely, there was observed lethargic behavior and significantly reduced walking distances for bees provided with a 72 h treatment of technical-grade chlorantraniliprole and each formulated product. CONCLUSION: This study provides evidence for the effect of long-term exposure of chlorantraniliprole on the survivorship and locomotor activity of honey bees. Bees receiving a more field-relevant short-term exposure survived and moved similarly to untreated bees, reiterating the relative safety of chlorantraniliprole exposure to adult honey bees at recommended label concentrations. © 2020 Society of Chemical Industry.


Assuntos
Locomoção , Animais , Criação de Abelhas , Abelhas , Inseticidas , ortoaminobenzoatos
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