Journal of Integrative Agriculture
·
2018
·
IF 1.042
Zhen-gang LIU,Huan-huan WANG,Chao-bin XUE
Laccase (EC 1.10.3.2) is known to oxidize various aromatic and nonaromatic compounds via a radical-catalyzed reaction, which generally includes two types of laccase, Lac1 and Lac2. Lac1 oxidizes toxic compounds in the diet, and Lac2 is known to play an important role in melanizing the insect exoskeleton. In this study, we cloned and sequenced the cDNA of the diamondback moth, Plutella xylostella Lac2 ( PxLac2 ), from the third instar larvae using polymerase chain reaction (PCR) and rapid amplification of cDNA ends techniques. The results showed that the full-length PxLac2 cDNA was 1 944 bp long and had an open reading frame of 1 794 bp. PxLac2 encoded a protein with 597 amino acids and had a molecular weight of 66.09 kDa. Moreover, we determined the expression levels of PxLac2 in different stages by quantitative PCR (qPCR). The results indicated that PxLac2 was expressed differently in different stages. We observed the highest expression level in pupae and the lowest expression level in fourth instar larvae. We also investigated the enzymatic properties of laccase, which had optimal activity at pH 3.0 and at 35°C. Under these optimal conditions, laccase had a Michaelis constant ( K m ) of 0.97 mmol L −1 , maximal reaction speed ( V m ) of 56.82 U mL −1 , and activation energy ( E a ) of 17.36 kJ mol −1 to oxidize 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid ammonium salt). Type II copper enhanced laccase activity below 0.8 mmol L −1 and reduced enzyme activity above 0.8 mmol L −1 with an IC 50 concentration of 1.26 mmol L −1 . This study provides insights into the biological function of laccase.
研究领域:
昆虫学
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分子生物学
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DOI
高影响因子
JOURNAL OF INSECT SCIENCE
·
2020
·Vol. 20
·期 5
·
IF 1.325
Fu Shuhui,Li Fangyuan,Yan Xizhong,Hao Chi
The diamondback moth, Plutella xylostella L. (Lepidoptera: Plutellidae) is one of the most destructive pests to cruciferous plants worldwide. The oligophagous moth primarily utilizes its host volatiles for foraging and oviposition. Chemosensory proteins (CSPs) are soluble carrier proteins with low molecular weight, which recognize and transport various semiochemicals in insect chemoreception. At present, there is limited information on the recognition of host volatiles by CSPs of P. xylostella. Here, we investigated expression patterns and binding characteristics of PxylCSP11 in P. xylostella. The open reading frame of PxylCSP11 was 369-bp encoding 122 amino acids. PxylCSP11 possessed four conserved cysteines, which was consistent with the typical characteristic of CSPs. PxylCSP11 was highly expressed in antennae, and the expression level of PxylCSP11 in male antennae was higher than that in female antennae. Fluorescence competitive binding assays showed that PxylCSP11 had strong binding abilities to several ligands, including volatiles of cruciferous plants, and (Z)-11-hexadecenyl acetate (Z11-16:Ac), a major sex pheromone of P. xylostella. Our results suggest that PxylCSP11 may play an important role in host recognition and spouse location in P. xylostella.
研究领域:
昆虫学
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分子生物学
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DOI
PubMed
高影响因子
JOURNAL OF APPLIED ENTOMOLOGY
·
2023
·Vol. 147
·期 7
·511-519
·
IF 1.9
Xi-Zhong Yan,Zhi-Yu Wang,Li Ma,Cheng-Fei Song,Jin-Yu Zhao,Chen-Zhu Wang,Chi Hao
Plutella xylostella Linnaeus (Lepidoptera: Plutellidae) is one of the most important pests of cruciferous vegetables. Mechanically damaged Mentha spicata Linnaeus (Lamiales: Lamiaceae) strongly repels P. xylostella adults; however, the repellent mechanism remains unclear. In this study, the repellent mechanism was explored based on the electroantennogram (EAG) and behavioural responses of P. xylostella to volatiles from the damaged M. spicata . First, the active volatile compounds in the headspace volatiles of damaged M. spicata were identified by gas chromatography-electroantennographic detection (GC-EAD) and gas chromatography–mass spectrometry (GC–MS). Furthermore, the EAG and behavioural responses of P. xylostella to these compounds were investigated. The GC-EAD results indicated that four compounds, 2,4-dimethylheptane, 4-methyloctane, 2-methylnonane, and myrcene induced EAG responses in female antennae. 2-methylnonane and myrcene elicited strong dose-dependent EAG responses starting at a dose of 1 μg/μL. Choice tests in a four-arm olfactometer showed significant repellent effects of the four compounds on P. xylostella adults at 100 μg/μL, and the repellent indices of 2,4-dimethylheptane, 4-methyloctane, 2-methylnonane, and myrcene were 70.0%, 76.7%, 66.7%, and 73.3% to mated females, respectively. Finally, oviposition repellence assays showed that female adults were significantly repelled by these compounds, and the oviposition repellent index for myrcene was 23.9%. 2,4-dimethylheptane, 4-methyloctane, 2-methylnonane, and myrcene mediate the repellence of wounded M. spicata to P. xylostella adults, suggesting that the four compounds contribute towards developing behavioural regulators of this important pest.
研究领域:
昆虫学
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植物化学
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DOI
高影响因子
JOURNAL OF ASIA-PACIFIC ENTOMOLOGY
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2023
·
IF 1.5
Chengfei Song,Xinyao Ma,Jiao Liu,Li Ma,Xingtao Qie,Xizhong Yan,Chi Hao
The diamondback moth (DBM), Plutella xylostella (L.), is a cosmopolitan obligate pest of cruciferous crops. Currently, DBMs management is largely dependent on broad-spectrum synthetic pesticides, which has led to the adverse effects on the environment, human health, and nontargeted organisms. Thus, alternative control methods are needed. The essential oils (EOs) derived from bioactive species may be developed as effective alternatives for the management of DBMs that is safe and eco-sustainable than conventional pesticides. In this study, we investigated electrophysiological (EAG) and behavioral responses of DBM adults to the thirteen non-host EOs of Acorus calamus , Ageratum conyzoides , Artemisia argyi , Chenopodium ambrosioides , Cymbopogon citratus , Foeniculum vulgare , Ocimum basilicum , Pelargonium hortorum , Perilla frutescens , Pogostemon cablin , Polygonum hydropiper , Rosmarinus officinalis , and Ruta graveolens in order to contribute to the development of low environmental impact management alternatives. EAG recordings revealed all the tested EOs significantly elicited EAG responses of DBM females, and the males were sensitive to the eleven EOs except A. conyzoides and O. basilicum . Meanwhile, EAG recordings of DBMs exhibited dose-dependent responses to these tested EOs in most cases. In Y-tube olfactometer bioassays, the EOs of A. calamus , C. citratus , P. hortorum , P. hydropiper , and R. graveolen demonstrated prominent repellent effects on DBM females at concentrations of 10 μg/μL or higher. The results of oviposition bioassays found the number of eggs on the two plants with the five tested EOs were less than that on the two plants with paraffin oil. And the oviposition indexes of the plants that fixed with the EOs of P. hortorum , R. graveolen , A. calamus , P. hydropiper , C. citratus , and paraffin oil were –71.81%, –59.43%, –57.46%, –51.11%, –35.41%, and 0.09%, respectively. These findings indicate that the five EOs, especially P. hydropiper EO, provide active and safe tools for natural repellents to prevent and control DBMs infestations of cruciferous vegetables.
研究领域:
昆虫学
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农业科学
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DOI
高影响因子
PEST MANAGEMENT SCIENCE
·
2023
·Vol. 79
·期 12
·5270-5282
·
IF 4.1
Xi-Zhong Yan,Li Ma,Xiao-Fei Li,Le Chang,Qing-Zhao Liu,Cheng-Fei Song,Jin-Yu Zhao,Xing-Tao Qie,Cai-Ping Deng,Chen-Zhu Wang,Chi Hao
BACKGROUND The diamondback moth, Plutella xylostella , has developed resistance to almost all insecticides used for its control. The ‘push–pull’ method has been shown as an effective control strategy to address this resistance challenge of P. xylostella . The key focus of the strategy is the identification of attractive or repellent volatile components. The aim of this study was to identify attractive volatile compounds released from host plants. Identified compounds were applied in the biological control of this pest. RESULTS Nine active compounds released into the headspace of seven cruciferous plant species were identified using gas chromatography–electroantennographic detection and gas chromatography–mass spectrometry. Electroantennographic detection-active compounds included five green leaf volatiles (hexanal, trans -2-hexen-1-ol, cis -3-hexen-1-ol, cis -3-hexenyl acetate, and 1-penten-3-ol), three isothiocyanates (isopropyl isothiocyanate, allyl isothiocyanate, and butyl isothiocyanate), and nonanal. Except for nonanal, all the identified green leaf volatiles and isothiocyanates elicited strong electrophysiological and behavioral responses in P. xylostella . The strongest attractive compounds, trans -2-hexen-1-ol and isopropyl isothiocyanate, were further evaluated in oviposition and field-trapping assays. Results showed that they both lured female moths to lay eggs, and were highly attractive to P. xylostella adults in field, especially when used in combination with yellow and green sticky boards. However, a blend of the two compounds showed no synergistic effect, but rather an antagonistic effect. CONCLUSIONS Green leaf volatiles and isothiocyanates were identified as key olfactory cues for host selection of P. xylostella . Trans -2- hexen-1-ol and isopropyl isothiocyanate were identified as candidate attractive compounds to serve in a ‘push–pull’ strategy for P. xylostella control. © 2023 Society of Chemical Industry.
研究领域:
昆虫学
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植物保护
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化学生态学
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DOI
PubMed
高影响因子
PEST MANAGEMENT SCIENCE
·
2020
·Vol. 76
·期 12
·4036-4045
·
IF 3.75
Yifan Li,Hong Sun,Zhen Tian,Xinxin Su,Yue Li,Xuan Ye,Yifei Zhou,Shengli Zheng,Jiyuan Liu,Yalin Zhang
BACKGROUND Insect glutathione S-transferases (GSTs) play a crucial role in insecticide detoxification. However, there remains a distinct lack of information regarding the role of GSTs in the detoxification of Tolfenpyrad (TFP) in insects. RESULTS Real-time quantitative PCR showed significant upregulation of PxGSTs after exposure to TFP for 6 h. An in vitro inhibition assay showed that TFP could inhibit PxGSTδ, PxGSTε and PxGSTσ, and the most pronounced inhibitory effect was on PxGSTσ. Metabolism assays displayed that PxGSTσ was superior to other test PxGSTs in metabolizing TFP. The molecular docking of TFP and PxGSTσ revealed that the H-bond provided by the sidechains of Tyr107 and Tyr162 were key to the detoxification of TFP by PxGSTσ. Further tests using mutant PxGSTσ proteins at the sites of Tyr107 (PxGSTσY107A) and Tyr162 (PxGSTσY162A) corroborated that the individual replacement of Tyr107 and Tyr162 could greatly weaken the binding and metabolic abilities to TFP. CONCLUSION Metabolic interactions between the Plutella xylostella (L.) GSTs (PxGSTs) and TFP were deciphered. This study illustrates the molecular metabolism mechanism of PxGSTσ towards TFP and provides theoretical underpinnings for the design and optimization of novel TFP-like insecticides. © 2020 Society of Chemical Industry
研究领域:
昆虫学
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分子生物学
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农药科学
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PubMed
高影响因子
Scientific Reports
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2017
·Vol. 7
·期 1
·1-10
·
IF 4.259
Huang Bin Bin,Zhang Shao Fei,Chen Peng Hao,Wu Gang
The dynamics of release and degradation of the microencapsulation formulation containing spinosad (SP) and emamectin benzoate (EM) were evaluated in the present study. SP and EM were microencapsulated using biodegradable poly-lactic acid (PLA) as the wall material. Their release from and degradation within the prepared SP and EM microspheres (SP-EM-microspheres) were studied. It was found that the encapsulation significantly prolonged the insecticide release. The release could be further extended if the external aqueous phase was pre-saturated with the insecticides and the microspheres were additionally coated with gelatin. On the other hand, increasing the water content of the emulsion or the hydrophilic polycaprolactone (PCL) content in the PLA/PCL mixture accelerated the release. Due to the photolysis and hydrolysis of SP and EM by sunlight, the toxicity of the non-encapsulated insecticides in water declined continuously from 0 through the 9 th day (d), and dissipated in 13 d. In contrast, an aqueous suspension containing 5% SP-EM-microspheres maintained a mostly constant toxicity to Plutella xylostella for 17 d. The biodegradable SP-EM-microspheres showed significantly higher long-term toxicity to P. xylostella due to lower release, reduced photolysis and hydrolysis of the encapsulated insecticides, which were affected by the varied preparation conditions.
研究领域:
农药科学
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环境生物学
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材料科学
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DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2025
·
IF 6.2
Mengjun Yun,Yu Xiong,Zhuobing Wang,Lianjie Xie,Hanwen Ye,Xiaofang Yuan,Weiyi He,Binqing Chen,Zhanjun Lu,Wei Chen
Plants perceive proteins from insect-derived oral secretion (OS) and regulate the classical endogenous hormone jasmonic acid to resist insects, but the role of abscisic acid (ABA) in this process is poorly understood. In this study, we used the specialist herbivorous caterpillar Plutella xylostella and cruciferous plants as a model to investigate how the ABA hormone responds to the OS and its core peptide from the insect. Through proteomics and Western blotting analysis, glucosinolate sulfatase 1 (GSS1) was identified in OS. Yeast library screening revealed that GSS1 and its 28-amino-acid core peptide (GSS1-P1) interact with ABA biosynthetic enzyme ABA1. Arabidopsis overexpressing GSS1 and plants treated with synthetic GSS1-P1 showed elevated ABA levels. Transcriptome analysis and RT-qPCR confirmed that GSS1-P1 upregulates WRKY18 and ABA1 expression, modulating ABA production. Both GSS1-P1 application and optimal ABA concentrations enhanced plant resistance to herbivory. Our study shows that GSS1 and its peptide stimulate ABA production, boosting plant–insect resistance and highlighting ABA’s potential role in pest-stress response.
研究领域:
植物学
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分子生物学
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昆虫学
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DOI
PubMed
高影响因子
CELLULAR MICROBIOLOGY
·
2018
·Vol. 20
·期 6
·e12827
·
IF 4.41
Lian Xu,Zhi-Zhen Pan,Jing Zhang,Li-Yang Niu,Jie Li,Zheng Chen,Bo Liu,Yu-Jing Zhu,Qing-Xi Chen
Cry2Ab, a pore-forming toxin derived from Bacillus thuringiensis , is widely used as a bio-insecticide to control lepidopteran pests around the world. A previous study revealed that proteolytic activation of Cry2Ab by Plutella xylostella midgut juice was essential for its insecticidal activity against P. xylostella , although the exact molecular mechanism remained unknown. Here, we demonstrated for the first time that proteolysis of Cry2Ab uncovered an active region (the helices α4 and α5 in Domain I), which was required for the mode of action of Cry2Ab. Either the masking or the removal of helices α4 and α5 mediated the pesticidal activity of Cry2Ab. The exposure of helices α4 and α5 did not facilitate the binding of Cry2Ab to P. xylostella midgut receptors but did induce Cry2Ab monomer to aggregate and assemble a 250-kDa prepore oligomer. Site-directed mutagenesis assay was performed to generate Cry2Ab mutants site directed on the helices α4 and α5, and bioassays suggested that some Cry2Ab variants that could not form oligomers had significantly lowered their toxicities against P. xylostella . Taken together, our data highlight the importance of helices α4 and α5 in the mode of action of Cry2Ab and could lead to more detailed studies on the insecticidal activity of Cry2Ab.
研究领域:
昆虫学
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分子生物学
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生物化学
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DOI
PubMed
高影响因子
Insects
·
2025
·Vol. 16
·期 3
·267
·
IF 2.9
Chunyan Yin,Ziyi Chen,Wei Chen,Zhenyu Wang
Simple SummaryManagingPlutella xylostellaandSpodoptera exiguahas traditionally relied on chemical insecticides, but resistance to these chemicals has become a major challenge in controlling these pests. Introducing new insecticides with a different mode of action is crucial for effective resistance management. Our study shows that fluxametamide exhibits strong insecticidal activity againstP. xylostellaandS. exigua. We assessed the susceptibility of field populations from key vegetable-growing regions in China and established a baseline of susceptibility to fluxametamide. The findings indicated thatP. xylostellaandS. exiguaare highly susceptible to this insecticide, and the baseline susceptibility data will serve as a reference for future resistance monitoring inP. xylostellaandS. exiguamanagement.Fluxametamide, an innovative isoxazoline insecticide, acts as an antagonist of γ-aminobutyric acid-gated chloride channels. Its distinct mode of action sets it apart, lacking known cross-resistance with current insecticides. This positions fluxametamide as a promising tool for addressing insecticide resistance in Lepidoptera, thysanoptera, coleoptera, and diptera pest insects. To develop and implement successful resistance management strategies, it is crucial to establish the baseline susceptibility to this insecticide before it is registered and widely used in China. In this study, we assessed the baseline susceptibility of two widespread lepidopteran pest species,Plutella xylostellaandSpodoptera exigua, to fluxametamide. The insecticide exhibited remarkably high efficacy against populations of the two lepidopteran species sampled in their primary distribution areas in China. ForP. xylostellaandS. exigua, the median lethal concentrations (LC50) ranged between 0.040 and 0.247 mg/L, and 0.211 and 0.761 mg/L, respectively. Among populations, there was a relative low variability in susceptibility to fluxametamide, showing a 6.18-fold difference forP. xylostellaand 3.61-fold forS. exigua. The suggested diagnostic concentrations forP. xylostellaandS. exiguawere 10 and 15 mg/L, respectively. Fluxametamide exhibited high toxicity to the selected resistant strains, which displayed strong resistance to abamectin, emamectin benzoate, and deltamethrin. No cross-resistance to fluxametamide was detected in the laboratory diamide-resistant strain. Our findings offer essential insights for crafting successful resistance management initiatives to maintain the effectiveness of fluxametamide against these significant pests.
研究领域:
昆虫学
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害虫管理
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农业科学
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产品关联
DOI
PubMed
高影响因子
PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY
·
2026
·
IF 4.8
Bingxue Li,Chao Xie,Minghui Yan,Bingwei Chen,Xiangdong Zeng,Xiyue Zhang,Guangyu Yu,Mengxue Luo,Shaoling Zhang,Minsheng You,Shijun You,Lei Xiong
UDP-glycosyltransferases (UGTs) are key Phase II detoxification enzymes involved in insect xenobiotic metabolism; however, the functional contribution of individual UGT genes to abamectin response in Plutella xylostella remains poorly understood. In this study, we characterized a candidate gene, PxUGT33W1 , using a combination of molecular, cellular, and genetic approaches. PxUGT33W1 exhibited broad expression across developmental stages and tissues, with elevated transcript levels in the midgut, epidermis, and reproductive organs. Its expression was significantly induced following abamectin exposure in a time-dependent manner, suggesting a stress-responsive pattern. Heterologous expression of PxUGT33W1 in Sf9 cells was associated with increased cellular survival under abamectin treatment, although whether this effect reflects direct enzymatic activity remains to be determined. CRISPR/Cas9-mediated knockout of PxUGT33W1 was associated with a 3.1-fold increase in larval susceptibility to abamectin, accompanied by a significant reduction in overall UGT activity toward α-naphthol. Furthermore, the knockout strain exhibited reduced fecundity, along with altered expression of vitellogenin ( Vg ), vitellogenin receptor ( VgR ), and juvenile hormone signaling-related genes. Collectively, these findings suggest that PxUGT33W1 may contribute to variation in abamectin susceptibility and reproductive performance in P. xylostella . However, direct biochemical evidence for abamectin metabolism by PxUGT33W1, such as its glycosylation, and the mechanistic basis of the observed phenotypes remain to be established.
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高影响因子
BMC BIOTECHNOLOGY
·
2019
·Vol. 19
·期 1
·1-11
·
IF 2.303
Zeng Liya,Liu Yongchang,Pan Jun,Liu Xiaowen
Background Norcantharidin (NCTD), a demethylated derivative of cantharidin (defensive toxin of blister beetles), has been reported to exhibit insecticidal activity against various types of agricultural pests. However, NCTD applications are limited by its poor water solubility and high dosage requirement. Nanoemulsions have attracted much attentions due to the transparent or translucence appearance, physical stability, high bioavailability and non-irritant in nature. In general, nanoemulsions with small droplet size can enhance the bioavailability of drugs, whereas this phenomenon is likely system dependent. In present study, NCTD nanoemulsions were developed and optimized to evaluate and improve the insecticidal activity of NCTD against Plutella xylostella (Lepidotera: Plutellidae) by a spontaneous emulsification method.Results Triacetin, Cremophor EL and butanol were selected as the constituents of NCTD nanoemulsions via solubility determination, emulsification efficiency and ternary phase diagram construction. Insecticidal activity of NCTD nanoemulsion was associated with the content of surfactant and cosurfactant: (1) Higher effective toxicity exhibited at Smix (surfactant to cosurfactant mass ratio) = 3:1 that may be associated with the changes in interfacial tension; (2) NCTD nanoemulsion at 3:7 < SOR (surfactant to oil mass ratio) < 6:4 was more effective at lower surfactant level, which was attributed to the relatively slow diffusion rate of NCTD hindering by excess surfactant. Interestingly, nanoemulsions with smaller droplets were not found to be more effective in our study.Conclusion sThe optimized NCTD nanoemulsion (triacetin/Cremophor EL/butanol (60/20/20, w/w)) exhibited effective insecticidal activity (LC50 60.414 mg/l, LC90 185.530 mg/l, 48 h) than the NCTD acetone solution (LC50 175.602 mg/L, LC90 303.050 mg/L, 48 h). Spontaneous emulsifying nanoemulsion employed to formulate this poor water-soluble pesticide is a potential system for agriculture application.
研究领域:
农业科学
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昆虫学
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药剂学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）