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Odontothrips loti (Haliday) (Thysanoptera: Thripidae) is one of the most serious pests on alfalfa, causing direct damage by feeding and indirect damage by transmitting plant viruses. This damage causes significant loss in alfalfa production. Semiochemicals offer opportunities to develop new approaches to thrips management. In this study, behavioral responses of female and male adults of O. loti to headspace volatiles from live female and male conspecifics were tested in a Y-tube olfactometer. The results showed that both male and female adults of O. loti were attracted to the odors released by conspecific males but not those released by females. Headspace volatiles released by female and male adults were collected using headspace solid-phase microextraction (HS-SPME). The active compound in the volatiles was identified by gas chromatography-mass spectrometry (GC-MS). The analysis showed that there was one major compound, (R)-lavandulyl (R)-2-methylbutanoate. The attractive activity of the synthetic aggregation pheromone compound was tested under laboratory and field conditions. In an olfactometer, both male and female adults showed significant preference for synthetic (R)-lavandulyl (R)-2-methylbutanoate at certain doses. Lures with synthetic (R)-lavandulyl (R)-2-methylbutanoate significantly increased the trap catches of sticky white traps at doses of 40-80 µg in the field. This study confirmed the production of aggregation pheromone by O. loti male adults and identified its active compound as (R)-lavandulyl (R)-2-methylbutanoate, providing a basis for population monitoring and mass trapping of this pest.
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The transmission of insect-borne viruses involves sophisticated interactions between viruses, host plants, and vectors. Chemical compounds play an important role in these interactions. Several studies reported that the plant virus tomato spotted wilt orthotospovirus (TSWV) increases host plant quality for its vector and benefits the vector thrips Frankliniella occidentalis. However, few studies have investigated the chemical ecology of thrips vectors, TSWV, and host plants. Here, we demonstrated that in TSWV-infected host plant Datura stramonium, (1) F. occidentalis were more attracted to feeding on TSWV-infected D. stramonium; (2) atropine and scopolamine, the main tropane alkaloids in D. stramonium, which are toxic to animals, were down-regulated by TSWV infection of the plant; and (3) F. occidentalis had better biological performance (prolonged adult longevity and increased fecundity, resulting in accelerated population growth) on TSWV-infected D. stramonium than on TSWV non-infected plants. These findings provide in-depth information about the physiological mechanisms responsible for the virus's benefits to its vector by virus infection of plant regulating alkaloid accumulation in the plant.
Assuntos
Alcaloides , Datura stramonium , Vírus de Plantas , Vírus de RNA , Solanum lycopersicum , Tisanópteros , Tospovirus , Animais , Tisanópteros/fisiologia , Tospovirus/fisiologia , Plantas , Doenças das Plantas/prevenção & controleRESUMO
As an endosymbiont, Wolbachia exerts significant effects on the host, including on reproduction, immunity, and metabolism. However, the study of Wolbachia in Thysanopteran insects, such as flower thrips Frankliniella intonsa, remains limited. Here, we assembled a gap-free looped genome assembly of Wolbachia strain wFI in a length of 1,463,884 bp (GC content 33.80%), using Nanopore long reads and Illumina short reads. The annotation of wFI identified a total of 1838 protein-coding genes (including 85 pseudogenes), 3 ribosomal RNAs (rRNAs), 35 transfer RNAs (tRNAs), and 1 transfer-messenger RNA (tmRNA). Beyond this basic description, we identified mobile genetic elements, such as prophage and insertion sequences (ISs), which make up 17% of the entire wFI genome, as well as genes involved in riboflavin and biotin synthesis and metabolism. This research lays the foundation for understanding the nutritional mutualism between Wolbachia and flower thrips. It also serves as a valuable resource for future studies delving into the intricate interactions between Wolbachia and its host.
Assuntos
Nanoporos , Tisanópteros , Wolbachia , Animais , Wolbachia/genética , Flores , Prófagos , RNA RibossômicoRESUMO
Megalurothrips usitatus (Bagnall) is a destructive pest of legumes, such as cowpea. The biology, population dynamics and control strategies of this pest have been well studied. However, the lack of a high-quality reference genome for M. usitatus has hindered the understanding of key biological questions, such as the mechanism of adaptation to feed preferentially on high-protein host plants and the resistance to proteinase inhibitors (PIs). In this study, we generated a high-resolution chromosome-level reference genome assembly (247.82 Mb, 16 chromosomes) of M. usitatus by combining Oxford Nanopore Technologies (ONT) and Hi-C sequencing. The genome assembly showed higher proportions of GC and repeat content compared to other Thripinae species. Genome annotation revealed 18,624 protein-coding genes, including 4613 paralogs that were preferentially located in TE-rich regions. GO and KEGG enrichment analyses of the paralogs revealed significant enrichment in digestion-related genes. Genome-wide identification uncovered 506 putative digestion-related enzymes; of those, proteases, especially their subgroup serine proteases (SPs), are significantly enriched in paralogs. We hypothesized that the diversity and expansion of the digestion-related genes, especially SPs, could be driven by mobile elements (TEs), which promote the adaptive evolution of M. usitatus to high-protein host plants with high serine protease inhibitors (SPIs). The current study provides a valuable genomic resource for understanding the genetic variation among different pest species adapting to different plant hosts.
Assuntos
Fabaceae , Tisanópteros , Animais , Tisanópteros/genética , Proteólise , Cromossomos , Fabaceae/genética , Serina Proteases/genética , Flores , FilogeniaRESUMO
Tomato is more prone to Tuta absoluta invasion and damages as compared to other host plants but the mechanism behind this preference has not been elucidated. Here, two contrasting host preference plants, tomato and eggplant, were used to investigate biochemical and transcriptomic modifications induced by T. absoluta infestation. Biochemical analysis at 0-72 h post T. absoluta infestation revealed significantly reduced concentrations of amino acid, fructose, sucrose, jasmonic acid, salicylic acid, and total phenols in tomato compared to eggplant, mainly at 48 h post T. absoluta infestation. Transcriptome analysis showed higher transcript changes in infested eggplant than tomato. Signaling genes had significant contributions to mediate plant immunity against T. absoluta, specifically genes associated with salicylic acid in eggplant. Genes from PR1b1, NPR1, NPR3, MAPKs, and ANP1 families play important roles to mitigate T. absoluta infestation. Our results will facilitate the development of control strategies against T. absoluta for sustainable tomato production.
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Mariposas , Solanum lycopersicum , Solanum melongena , Animais , Perfilação da Expressão Gênica , Humanos , Solanum lycopersicum/genética , Mariposas/fisiologia , Solanum melongena/genética , TranscriptomaRESUMO
Two closely related thrips species, Frankliniella occidentalis and Frankliniella intonsa, are important pests on agricultural and horticultural crops. They have several similarities, including occurrence patterns, host range, and aggregation pheromone compounds. However, there are very few reports about the chemosensory genes and olfactory mechanisms in these two species. To expand our knowledge of the thrips chemosensory system, we conducted antennal transcriptome analysis of two thrips species, and identified seven odorant-binding proteins (OBPs) and eight chemosensory proteins (CSPs) in F. occidentalis, as well as six OBPs and six CSPs in F. intonsa. OBPs and CSPs showed high sequence identity between the two thrips species. The RT-qPCR results showed that the orthologous genes FoccOBP1/3/4/5/6, FintOBP1/3/4/6, FoccCSP1/2/3, and FintCSP1/2 were highly expressed in male adults. Molecular docking results suggested that orthologous pairs FoccOBP4/FintOBP4, FoccOBP6/FintOBP6, and FoccCSP2/FintCSP2 might be involved in transporting the major aggregation pheromone compound neryl (S)-2-methylbutanoate, while orthologous pairs FoccOBP6/FintOBP6, FoccCSP2/FintCSP2, and FoccCSP3/FintCSP3 might be involved in transporting the minor aggregation pheromone compound (R)-lavandulyl acetate. These results will provide a fundamental basis for understanding the molecular mechanisms of pheromone reception in the two thrips species.
Assuntos
Tisanópteros , Masculino , Animais , Tisanópteros/genética , Simulação de Acoplamento Molecular , Odorantes , Perfilação da Expressão Gênica , FeromôniosRESUMO
The beet armyworm, Spodoptera exigua, is a highly polyphagous pest originated from Southeast Asia but has spread globally, attacking economically important crops and fruits. Bistrifluron insecticide is one of the highly active insect growth regulators that has been reported to inhibit development and longevity in other lepidopteran species and could be used in the control of S. exigua. In the present study, the age-stage, two-sex life table technique was applied to assess the sublethal effects of bistrifluron on biological traits and vitellogenin gene (SeVg) expression when 2nd instar larvae fed to sublethal concentrations (LC10, LC20 and LC40) of bistrifluron. Mean generation time from eggs to adults was longer at LC40 (37.79 ± 0.81 d) and LC20 (37.04 ± 0.72) compared to the LC10 (36.89 ± 0.63 d) and control groups (36.07 ± 0.38 d). Fecundity of female at LC40 (279.17 ± 42.8 eggs), LC20 (347 ± 35.4 eggs) and LC10 (411.58 ± 42.38 eggs) were significantly lower than the control treatment (532.47 ± 7.13). Furthermore, the lower intrinsic rates of increase (LC40; r = 0.1207 ± 0.009, LC20; r = 0.1329 ± 0.009 and LC10; r = 0.14398 ± 0.009 compared to the control r = 0.164 ± 0.0076), was observed along with significantly extended mean generation times (LC40; T = 34.825 ± 0.317 days, LC20; T = 33.27 ± 0.368 days and LC10; T = 31.899 ± 0.398 days compared to the control 30.927 ± 0.255 days). Furthermore, the contents of energy reserve macronutrients (carbohydrate, lipid and protein) significantly reduced in dose and time dependent manner in treated insects as compared to control. Furthermore, the expression level of SeVg mRNA significantly decreased by 43.8% in the female adults when one-day-old second instar larvae were treated with sublethal concentrations of bistrifluron in comparison with the control. Documenting these sublethal effects is a vital, and often overlooked factor, in assessing the overall efficacy of insecticides in the management of pest populations.
Assuntos
Inseticidas , Vitelogeninas , Animais , Feminino , Hidrocarbonetos Halogenados , Inseticidas/toxicidade , Larva , Nutrientes , Compostos de Fenilureia , Spodoptera/genética , Vitelogeninas/genéticaRESUMO
How herbivorous insects adapt to host plants is a key question in ecological and evolutionary biology. The fall armyworm, (FAW) Spodoptera frugiperda (J.E. Smith), although polyphagous and a major pest on various crops, has been reported to have a rice and corn (maize) feeding strain in its native range in the Americas. The species is highly invasive and has recently established in China. We compared behavioral changes in larvae and adults of a corn population (Corn) when selected on rice (Rice) and the molecular basis of these adaptational changes in midgut and antennae based on a comparative transcriptome analysis. Larvae of S. frugiperda reared on rice plants continuously for 20 generations exhibited strong feeding preference for with higher larval performance and pupal weight on rice than on maize plants. Similarly, females from the rice selected population laid significantly more eggs on rice as compared to females from maize population. The most highly expressed DEGs were shown in the midgut of Rice vs. Corn. A total of 6430 DEGs were identified between the populations mostly in genes related to digestion and detoxification. These results suggest that potential adaptations for feeding on rice crops, may contribute to the current rapid spread of fall armyworm on rice crops in China and potentially elsewhere. Consistently, highly expressed DEGs were also shown in antennae; a total of 5125 differentially expressed genes (DEGs) s were identified related to the expansions of major chemosensory genes family in Rice compared to the Corn feeding population. These results not only provide valuable insight into the molecular mechanisms in host plants adaptation of S. frugiperda but may provide new gene targets for the management of this pest.
Assuntos
Spodoptera/genética , Spodoptera/fisiologia , Adaptação Fisiológica/genética , Animais , China , Produtos Agrícolas/parasitologia , Fenômenos Fisiológicos do Sistema Digestório , Comportamento Alimentar/fisiologia , Feminino , Ontologia Genética , Genes de Insetos , Herbivoria/genética , Herbivoria/fisiologia , Adaptação ao Hospedeiro/genética , Adaptação ao Hospedeiro/fisiologia , Especificidade de Hospedeiro/genética , Especificidade de Hospedeiro/fisiologia , Interações Hospedeiro-Parasita/genética , Interações Hospedeiro-Parasita/fisiologia , Larva/fisiologia , Masculino , Oryza/parasitologia , Oviposição/fisiologia , Spodoptera/patogenicidade , Transcriptoma , Zea mays/parasitologiaRESUMO
Insect predators, in general, play an important role in regulating pest populations in agricultural systems, but may be negatively affected by pesticides used in pest management. Convergent lady beetle, Hippodamia convergens Guerin-Meneville (Coleoptera: Coccinellidae) is known as an important biological control agent of soft-bodied insect pests. The development of Integrated Pest Management (IPM) program against insect pests requires an assessment of the side effect of insecticides on biological control agents. In the present work, we assessed the sublethal effects of an insect growth regulator, Pyriproxyfen (juvenile hormone mimic) on a common aphidophagous beetle, H. convergens by computing its demographic parameters through age-stage, two-sex life table theory. Present results showed that sublethal (LC10 and LC30) concentrations of tested insecticide prolonged the pre-adult developmental duration while adult longevity, fecundity and fertility were reduced following treatment compared with control. However, total pre-ovipositional period (TPOP) was declined with the increasing trend of insecticide concentration. In additions, population growth parameters such as intrinsic rate of increase r, finite rate of increase λ and net reproductive rate R0 were dramatically reduced in H. convergens population when they treated with sublethal concentrations pyriproxyfen. Therefore, the results obtained through this study reflected that pyriproxyfen impairs the population growth parameters and could reduce the biological services provided by H. convergens. Thus, more attention should be paid to the use of this insecticide in IPM program.
Assuntos
Besouros/efeitos dos fármacos , Inseticidas/efeitos adversos , Hormônios Juvenis/efeitos adversos , Piridinas/efeitos adversos , Animais , Besouros/crescimento & desenvolvimento , Feminino , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Masculino , Pupa/efeitos dos fármacos , Pupa/crescimento & desenvolvimentoRESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
RESUMO
The beet armyworm (Spodoptera exigua) is a highly polyphagous agricultural pest that is distributed worldwide. However, the adaptive mechanisms of S. exigua for various insecticides and defensive substances in host plants are unknown. Insect P450 monooxygenases play an important role in the detoxification of plant toxins and insecticides, leading to insecticides resistance. We investigated the induced effects of xanthotoxin exposure on detoxification enzyme activity and larval tolerance to α-cypermethrin in S. exigua. Our results showed that the lethal concentration (LC50) of α-cypermethrin for xanthotoxin-exposed larvae was 2.1-fold higher than in the control. Moreover, cytochrome P450 enzyme activity was significantly elevated by upregulation of P450 genes in treated larvae. RT-qPCR results showed that CYP9A10 expression level was significantly increased in all treatments, while maximal expression level was observed in xanthotoxin+α-cypermethrin-fed larvae. RNAi-mediated silencing of CYP9A10 further increased mortality by 18%, 26% and 35% at 48â¯h and by 27%, 43% and 55% at 72â¯h when larvae were exposed to diets containing chemicals as compared to the control. The results show that CYP9A10 might play an important role in xanthotoxin and α-cypermethrin detoxification in S. exigua. RNAi-mediated silencing could provide an effective synergistic agent for pest control or insecticide resistance management.
Assuntos
Inseticidas , Metoxaleno , Animais , Sistema Enzimático do Citocromo P-450 , Larva , Piretrinas , Interferência de RNA , SpodopteraRESUMO
The osmotic membrane bioreactor (OMBR) is an emerging technology that uses water osmosis to accomplish separation of biomass from the treated effluent; however, accumulation of salts in the wastewater due to water flux and loss of draw solute because of reverse salt flux seriously hinder OMBR development. In this study, a hybrid OMBR-electrodialysis (ED) system was proposed and investigated to alleviate the salinity buildup. The use of an ED (3 V applied) could maintain a relatively low conductivity of 8 mS cm(-1) in the feed solution, which allowed the OMBR to operate for 24 days, about 6 times longer than a conventional OMBR without a functional ED. It was found that the higher the voltage applied to the ED, the smaller area of ion-exchange membrane was needed for salt separation. The salts recovered by the ED were successfully reused as a draw solute in the OMBR. At an energy consumption of 1.88-4.01 kWh m(-3), the hybrid OMBR-ED system could achieve a stable water flux of about 6.23 L m(-2) h(-1) and an efficient waste salt recovery of 1.26 kg m(-3). The hybrid OMBR-ED system could be potentially more advantageous in terms of less waste saline water discharge and salt recovery compared with a combined OMBR and reverse osmosis system. It also offers potential advantages over the conventional OMBR+post ED treatment in higher water flux and less wastewater discharge.
Assuntos
Reatores Biológicos , Diálise/instrumentação , Diálise/métodos , Membranas Artificiais , Osmose , Salinidade , Cloreto de Sódio/análise , Eletricidade , Estudos de Viabilidade , Filtração/instrumentação , Soluções , Termodinâmica , Águas Residuárias/química , Purificação da Água/instrumentaçãoRESUMO
Spinetoram is a spinosyn, which is a unique class of natural insecticide. Because of its novel mode of action, spinetoram is more potent and faster acting than other insecticides, even the older spinosyn product, spinosad. On account of being efficient on insect order Lepidoptera, spinetoram provides a new alternative for control of Plutella xylostella (L.) (Lepidoptera: Plutellidae), which are resistant to other chemicals. To determine the current situation of resistance of P. xylostella to spinetoram, the susceptibility of 16 P. xylostella populations from different regions of China or different time in addition to the population from laboratory was assessed using a leaf dip bioassay. The variation in spinetoram susceptibility among the 16 field populations was narrow, with median lethal concentrations (LC50 values) ranging from 0.131 to 1.001 mg/liter. Toxicity ratios (TRs) ranged from 1.5 to 7.6 and were 5.6 and 7.6 for populations SY-2 and FX-1, respectively, indicating some low level of tolerance in these populations. A discriminating concentration (a concentration that can detect the occurrence of resistance in a population) of 10 mg/liter, which was identified based on the pooled toxicological data, caused 100% mortality in all nine tested populations. The baseline susceptibility data reflect the natural variation of the P. xylostella populations to spinetoram rather than variation caused by previous exposure.
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Inseticidas , Macrolídeos , Mariposas , Animais , ChinaRESUMO
To compare the performance of Frankliniella occidentalis (Pergande) and native Frankliniella intonsa (Trybom) on cucumber and tomato leaves in laboratory, life history characters were investigated, and life tables were constructed using the method of age-stage, two-sex table life. Compared with tomato leaf, there were shorter total preoviposition period (TPOP), higher fecundity, longer female longevity, and higher intrinsic rate of increase (r) of both F. occidentalis and F. intonsa on cucumber leaf. Meanwhile, on cucumber leaf, the shorter TPOP, higher fecundity, longer female longevity, and higher value of r were found on population of F. intonsa but on tomato leaf which were found on population of F. occidentalis. From above, cucumber leaf was the preference to population development of both F. occidentalis and F. intonsa compared with tomato leaf. Nevertheless, on cucumber leaf, population of F. intonsa would grow faster than that of F. occidentalis, which was the opposite on tomato leaf. As to the population development in fields, much more factors would be taken into account, such as pollen, insecticide resistance, and effects of natural enemies etc.
Assuntos
Cucumis sativus/parasitologia , Solanum lycopersicum/parasitologia , Tisanópteros/fisiologia , Animais , Feminino , Fertilidade/fisiologia , Espécies Introduzidas , Estágios do Ciclo de Vida , Longevidade , Masculino , Folhas de Planta/parasitologia , Dinâmica Populacional , Especificidade da Espécie , Tisanópteros/crescimento & desenvolvimentoRESUMO
The hyperbolic frequency-modulated (HFM) waveform has an inherent Doppler-invariant property. It is more conducive than the conventional linear frequency-modulated (LFM) waveform to high speed moving target imaging. In order to apply the HFM waveform to existing inverse synthetic aperture radar (ISAR) imaging systems, a new pulse compression algorithm is proposed. First, the received HFM echoes are demodulated with the transmitted signal, which is called "decurve" in this paper. By this operation, the bandwidth of the demodulated echoes is effectively reduced and can be processed by the existing narrow-band receiver. Then, the phase of the decurved HFM echoes is analyzed, and thus, the pulse compression is accomplished by space-variant phase compensation. In addition, the space-variant phase compensation is realized by resampling and fast Fourier transform (FFT) with high computational efficiency. Finally, numerical results illustrate the effectiveness of the proposed method.
RESUMO
The western flower thrips (WFT), Frankliniella occidentalis, a world-wide invasive insect, causes agricultural damage by directly feeding and by indirectly vectoring Tospoviruses, such as Tomato spotted wilt virus (TSWV). We characterized the transcriptome of WFT and analyzed global gene expression of WFT response to TSWV infection using Illumina sequencing platform. We compiled 59,932 unigenes, and identified 36,339 unigenes by similarity analysis against public databases, most of which were annotated using gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Within these annotated transcripts, we collected 278 sequences related to insecticide resistance. GO and KEGG analysis of different expression genes between TSWV-infected and non-infected WFT population revealed that TSWV can regulate cellular process and immune response, which might lead to low virus titers in thrips cells and no detrimental effects on F. occidentalis. This data-set not only enriches genomic resource for WFT, but also benefits research into its molecular genetics and functional genomics.
Assuntos
Resistência a Medicamentos/genética , Insetos Vetores/genética , Inseticidas/farmacologia , Tisanópteros/genética , Transcriptoma , Animais , Expressão Gênica , Genes de Insetos , Interações Hospedeiro-Patógeno , Proteínas de Insetos/genética , Insetos Vetores/efeitos dos fármacos , Insetos Vetores/virologia , Espécies Introduzidas , Anotação de Sequência Molecular , Subunidades Proteicas/genética , Receptores Nicotínicos/genética , Análise de Sequência de RNA , Tisanópteros/efeitos dos fármacos , Tisanópteros/virologia , Tospovirus/fisiologiaRESUMO
Quantitative feeding behaviors were analyzed by electronic penetration graph technique to evaluate the resources utilization efficiency of the solenopsis mealybug, Phenacoccus solenopsis (Tinsley) (Hemiptera: Pseudococcidae), transferred to a novel host. Both nonphloem and phloem factors were contributed to the host availability during host shift; while only "prephloem" factor was involved with their offspring's fitness to the transferred host, on which they fed as effectively as their mothers did on the origin host. Different performances on different hosts were supposed to have relations with the diverse phloem components, rather than feeding behaviors. P. solenopsis could try and exploit an efficient stylet pathway to reach the phloem, which would be an importance factor to account for the expansion of the host range and adaptations to different hosts. High efficient feeding behaviors of P. solenopsis in the current study manifested its capability of resource utilization to the novel host, which was suggested to be advantageous for its host shift, and to be the explanation for rapid host shifts associated with its broad host range and quick settlement.
Assuntos
Hemípteros/fisiologia , Especificidade de Hospedeiro , Animais , Comportamento Alimentar , Feminino , Gossypium , Solanum lycopersicum , Distribuição AleatóriaRESUMO
The current study examined the effects of honey solution and water access on feeding behavior and survival of starving solenopsis mealybugs, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae). The electrical penetration graph technique and an artificial membrane system were used to check whether P. solenopsis could imbibe free water or other liquid, such as the honey solution used here, in its natural environment. The recorded electrical penetration graph waveforms revealed that P. solenopsis could continuously imbibe water-honey solution for several hours, which indicated that honey solution and water acquisition could possibly occur when P. solenopsis had access to such liquids in its natural environment. Waveforms of water-honey solution feeding alternated between two distinct feeding phases in a regular pattern, which was assumed to reflect inherent habits of feeding attempts. The effects of honey solution and water acquisition on survival of P. solenopsis was also examined. Comparison between P. solenopsis in different treatments (starved, water feeding, honey solution feeding, and cotton plant feeding) suggested that 1) P. solenopsis could accept but did not favor feeding on water or the honey solution, and 2) this feeding could prolong its survival, but had no effect on body size.
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Comportamento Alimentar , Hemípteros/fisiologia , Mel , Longevidade , Água/metabolismo , Animais , FemininoRESUMO
BACKGROUND: Insect RDL (resistant to dieldrin) receptors are essential pentameric ligand-gated chloride channels that mediate the neuroinhibitory effect of GABA, the chief inhibitory neurotransmitter in the central nervous system. These receptors serve as primary targets for various insecticides, including noncompetitive antagonists (NCAs) such as cyclodiene organochlorines and phenylpyrazoles, as well as allosteric modulators like meta-diamides and isoxazolines. This study focuses on a newly discovered A2'N mutation within the RDL receptors, identified in fipronil-resistant planthoppers. Despite in vitro electrophysiological studies have proposed its role in conferring target-site resistance, in vivo genetic functional validation of this mutation remains unexplored. RESULTS: Our research employed toxicity bioassays, assessing various Rdl genotypes against a spectrum of insecticides, including fipronil, α-endosulfan, broflanilide, and isocycloseram. Results revealed distinct resistance profiles for A2'N and A2'S mutants, indicating different binding interactions of RDL receptors with NCAs. Significantly, the A2'N heterozygote showed substantial resistance to fipronil, despite its homozygous lethality. Molecular modeling and docking simulations further supported these findings, highlighting unique binding poses for fipronil and α-endosulfan. CONCLUSION: This study confirmed that A2'N mutation of the RDL GABA receptor confer high resistance to fipronil in vivo. The observed resistance in A2'N mutants is likely attributable to a steric hindrance mechanism, wherein the introduction of larger side chains hampers fipronil binding, even in a heterozygous state. © 2023 Society of Chemical Industry.
Assuntos
Inseticidas , Pirazóis , Receptores de GABA , Animais , Receptores de GABA/genética , Receptores de GABA/metabolismo , Drosophila , Inseticidas/farmacologia , Endossulfano , Mutação , Resistência a Inseticidas/genéticaRESUMO
Psychoactive substances (PS) have become emerging contaminants in aquatic environments, characterized by their wide distribution, high persistence, bioaccumulation and toxicity. They are difficult to be completely removed in sewage treatment plants due to their high stability under different conditions. The incomplete removal of PS poses a threat to the aquatic animals and can also lead to human health problems through accumulation in the food chain. PS has become a huge burden on global health systems. Therefore, finding an effective technology to completely remove PS has become a "hot topic" for researchers. The methods for removal PS include physical techniques, chemical methods and biological approaches. However, there is still a lack of comprehensive and systematic exploration of these methods. This review aims to address this gap by providing a comprehensive overview of traditional strategies, highlighting recent advancements, and emphasizing the potential of natural aquatic plants in removing trace PS from water environments. Additionally, the degradation mechanisms that occur during the treatment process were discussed and an evaluation of the strengths and weaknesses associated with each method was provided. This work would help researchers in gaining a deeper understanding of the methodologies employed and serve as a reference point for future research endeavors and promoting the sustainable and large-scale application of PS elimination.