Micromelalopha Troglodyta Research Articles

Cloning of three epsilon-class glutathione S-transferase genes from Micromelalopha troglodyta (Graeser) (Lepidoptera: Notodontidae) and their response to tannic acid.

Micromelalopha troglodyta (Graeser) is an important pest of poplar in China, and glutathione S-transferase (GST) is an important detoxifying enzyme in M. troglodyta. In this paper, three full-length GST genes from M. troglodyta were cloned and identified. These GST genes all belonged to the epsilon class (MtGSTe1, MtGSTe2, and MtGSTe3). Furthermore, the expression of these three MtGSTe genes in different tissues, including midguts and fat bodies, and the MtGSTe expression in association with different concentrations of tannic acid, including 0.001, 0.01, 0.1, 1, and 10 mg ml-1, were analysed in detail. The results showed that the expression levels of MtGSTe1, MtGSTe2, and MtGSTe3 were all the highest in the fourth instar larvae; the expression levels of MtGSTe1 and MtGSTe3 were the highest in fat bodies, while the expression level of MtGSTe2 was the highest in midguts. Furthermore, the expression of MtGSTe mRNA was induced by tannic acid in M. troglodyta. These studies were helpful to clarify the interaction between plant secondary substances and herbivorous insects at a deep level and provided a theoretical foundation for controlling M. troglodyta.

Cap 'n' Collar C and Aryl Hydrocarbon Receptor Nuclear Translocator Facilitate the Expression of Glutathione S-Transferases Conferring Adaptation to Tannic Acid and Quercetin in Micromelalopha troglodyta (Graeser) (Lepidoptera: Notodontidae).

Micromelalopha troglodyta (Graeser) (Lepidoptera: Notodontidae) is a notorious pest of poplar. Coevolution with poplars rich in plant secondary metabolites prompts M. troglodyta to expand effective detoxification mechanisms against toxic plant secondary metabolites. Although glutathione S-transferases (GSTs) play an important role in xenobiotic detoxification in M. troglodyta, it is unclear how GSTs act in response to toxic secondary metabolites in poplar. In this study, five GST gene core promoters were accurately identified by a 5' loss luciferase reporter assay, and the core promoters were significantly induced by two plant secondary metabolites in vitro. Two transcription factors, cap 'n' collar C (CncC) and aryl hydrocarbon receptor nuclear translocator (ARNT), were cloned in M. troglodyta. MtCncC and MtARNT clustered well with other insect CncCs and ARNTs, respectively. In addition, MtCncC and MtARNT could bind the MtGSTt1 promoter and strongly improve transcriptional activity, respectively. However, MtCncC and MtARNT had no regulatory function on the MtGSTz1 promoter. Our findings revealed the molecular mechanisms of the transcription factors MtCncC and MtARNT in regulating the GST genes of M. troglodyta. These results provide useful information for the control of M. troglodyta.

Evaluation of the Ecological Environment Affected by Cry1Ah1 in Poplar.

Populus is a genus of globally significant plantation trees used widely in industrial and agricultural production. Poplars are easily damaged by Micromelalopha troglodyta and Hyphantria cunea, resulting in decreasing quality. Bt toxin-encoded by the Cry gene has been widely adopted in poplar breeding because of its strong insect resistance. There is still no comprehensive and sufficient information about the effects of Cry1Ah1-modified (CM) poplars on the ecological environment. Here, we sampled the rhizosphere soils of field-grown CM and non-transgenic (NT) poplars and applied 16S rRNA and internal transcribed spacer amplicon Illumina MiSeq sequencing to determine the bacterial community associated with the CM and NT poplars. Based on the high-throughput sequencing of samples, we found that the predominant taxa included Proteobacteria (about 40% of the total bacteria), Acidobacteria (about 20% of the total bacteria), and Actinobacteria (about 20% of the total bacteria) collected from the natural rhizosphere of NT and CM poplars. In addition, studies on the microbial diversity of poplar showed that Cry1Ah1 expression has no significant influence on rhizosphere soil alkaline nitrogen, but significantly affects soil phosphorus, soil microbial biomass nitrogen, and carbon. The results exhibited a similar bacterial community structure between CM varieties affected by the expression of Cry1Ah1 and non-transgenic poplars. In addition, Cry1Ah1 expression revealed no significant influence on the composition of rhizosphere microbiomes. These results broadly reflect the effect of the Bt toxin-encoded by Cry1Ah1 on the ecology and environment and provide a clear path for researchers to continue research in this field in the future.

Analysis of the Antennal Transcriptome and Identification of Tissue-specific Expression of Olfactory-related Genes in Micromelalopha troglodyta (Lepidoptera: Notodontidae).

Micromelalopha troglodyta (Graeser) has been one of the most serious pests on poplars in China. We used Illumina HiSeq 2000 sequencing to construct an antennal transcriptome and identify olfactory-related genes. In total, 142 transcripts were identified, including 74 odorant receptors (ORs), 32 odorant-binding proteins (OBPs), 13 chemosensory proteins (CSPs), 20 ionotropic receptors (IRs), and 3 sensory neuron membrane proteins (SNMPs). The genetic relationships were obtained by the phylogenetic tree, and the tissue-specific expression of important olfactory-related genes was determined by quantitative real-time PCR (qRT–PCR). The results showed that most of these genes are abundantly expressed in the antennae and head. In most insects, olfaction plays a key role in foraging, host localization, and searching for mates. Our research lays the foundation for future research on the molecular mechanism of the olfactory system in M. troglodyta. In addition, this study provides a theoretical basis for exploring the relationship between M. troglodyta and their host plants, and for the biological control of M. troglodyta using olfactory receptor as targets.

Exploring miRNA-mRNA regulatory modules responding to tannic acid stress in Micromelalopha troglodyta (Graeser) (Lepidoptera: Notodontidae) via small RNA sequencing.

MicroRNAs (miRNAs) are small noncoding RNAs (sRNAs) that regulate gene expression by inhibiting translation or degrading mRNA. Although the functions of miRNAs in many biological processes have been reported, there is currently no research on the possible roles of miRNAs in Micromelalopha troglodyta (Graeser) involved in the response of plant allelochemicals. In this article, six sRNA libraries (three treated with tanic acid and three control) from M. troglodyta were constructed using Illumina sequencing. From the results, 312 known and 43 novel miRNAs were differentially expressed. Notably, some of the most abundant miRNAs, such as miR-432, miR-541-3p, and miR-4448, involved in important physiological processes were also identified. To better understand the function of the targeted genes, we performed Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. The results indicated that differentially expressed miRNA targets were involved in metabolism, development, hormone biosynthesis, and immunity. Finally, we visualized a miRNA-mRNA regulatory module that supports the role of miRNAs in host-allelochemical interactions. To our knowledge, this is the first report on miRNAs responding to tannic acid in M. troglodyta. This study provides indispensable information for understanding the potential roles of miRNAs in M. troglodyta and the applications of these miRNAs in M. troglodyta management.

Transcriptome Profiling of Micromelalopha troglodyta (Lepidoptera: Notodontidae) Larvae under Tannin Stress Using Solexa Sequencing Technology

Abstract Tannins are a large group of polyphenolic compounds and natural protective substances for plant survival. The differentially expressed genes (DEGs) of Micromelalopha troglodyta (Graeser) under tannin stress were studied by Solexa sequencing technology. A total of 51,797,038–54,991,822 and 51,674,478–52,307,172 clean reads were obtained from the tannin treatment (TT) library and the control (CK) library transcriptomes, respectively, and assembled into 21,236 nonredundant consensus sequences. The expression of 1,627 unigenes in the TT library was remarkably different from that of the CK library; 885 genes were upregulated, and 742 genes were downregulated (P ≤ 0.001). The expression of 18 DEGs was detected by real-time fluorescent quantitative PCR, and the trend of gene expression was consistent with that of transcriptome data. In the biological process category, the DEGs were primarily related to cellular processes, metabolic processes, and single-organism processes. In the molecular function category, the DEGs were mainly involved in binding and catalytic activity, and in the cellular component category, the DEGs were mainly related to the cell, cell part, and organelle. Pathway enrichment analysis indicated that drug metabolism-cytochrome P450 and glutathione metabolism may be associated with detoxification-related processes under tannin stress, and glutathione S-transferases and other detoxification enzyme genes play an important role in detoxifying tannins in M. troglodyta larvae. This study also provides important resources for further study of the genes related to pesticide targets and metabolic processes in M. troglodyta.

Exogenous Gene Expression and Insect Resistance in Dual Bt Toxin Populus × euramericana 'Neva' Transgenic Plants.

Bacillus thuringiensis (Bt) insecticidal protein genes are important tools in efforts to develop insect resistance in poplar. In this study, the Cry1Ac and Cry3A Bt toxin genes were simultaneously transformed into the poplar variety Populus × euramericana ‘Neva’ by Agrobacterium-mediated transformation to explore the exogenous gene expression and insect resistance, and to examine the effects of Bt toxin on the growth and development of Anoplophora glabripennis larvae after feeding on the transgenic plant. Integration and expression of the transgenes were determined by molecular analyses and the insect resistance of transgenic lines was evaluated in feeding experiments. Sixteen transgenic dual Bt toxin genes Populus × euramericana ‘Neva’ lines were obtained. The dual Bt toxin genes were expressed at both the transcriptional and translational levels; however, Cry3A protein levels were much higher than those of Cry1Ac. Some of the transgenic lines exhibited high resistance to the first instar larvae of Hyphantria cunea and Micromelalopha troglodyta, and the first and second instar larvae and adults of Plagiodera versicolora. Six transgenic lines inhibited the growth and development of A. glabripennis larvae. The differences in the transcriptomes of A. glabripennis larvae fed transgenic lines or non-transgenic control by RNA-seq analyses were determined to reveal the mechanism by which Bt toxin regulates the growth and development of longicorn beetle larvae. The expression of genes related to Bt prototoxin activation, digestive enzymes, binding receptors, and detoxification and protective enzymes showed significant changes in A. glabripennis larvae fed Bt toxin, indicating that the larvae responded by regulating the expression of genes related to their growth and development. This study lay a theoretical foundation for developing resistance to A. glabripennis in poplar, and provide a foundation for exploring the mechanism of Bt toxin action on Cerambycidae insects.

Effects of Bt-Cry1Ah1 Transgenic Poplar on Target and Non-Target Pests and Their Parasitic Natural Enemy in Field and Laboratory Trials

Increasing areas of artificial afforestation and poplar monoculture in China have led to serious problems with insect pests. The development of genetic engineering technology, such as transgenic modification with Bacillus thuringiensis (Bt) genes, provides novel solutions to the pest problem. We generated a Bt-Cry1Ah1 gene incorporating codon optimization and transferred it into Populus deltoides × P. euramericana cv “Nanlin895” using an Agrobacterium-mediated method. The resulting Bt-Cry1Ah1 transgenic poplars were planted in the field with permission from the State Forestry Administration in 2017. Field and laboratory studies were conducted in Jiangsu, China, to investigate the effects of these transgenic poplars expressing the Cry1Ah1 protein on target and non-target pests and their parasitic natural enemy. Target pests included Hyphantria cunea (Lepidoptera, Arctiidae), Micromelalopha troglodyta (Lepidoptera, Notodontidae), and Clostera anachoreta (Lepidoptera, Notodontidae). Plagiodera versicolora (Coleoptera, Chrysomelidae) served as the non-target pest. Laboratory trials showed that the six transgenic poplar lines exhibited resistance against the target insects. The corrected mortality rates of the target pest larvae fed leaves from the six lines were as high as 87.0%, significantly higher than that of the control. However, the corrected mortality rate of the non-target pest larvae was markedly lower and did not differ significantly from that of the control. Field experiments showed that transgenic poplar exhibited resistance against H. cunea and M. troglodyta. Field mortality rates were slightly higher than laboratory mortality rates. In addition, we investigated Chouioia cunea (Hymenoptera, Eulophidae) as a parasitoid of H. cunea pupae that had been fed transgenic poplar leaves. The emergence time, parasitism rate, and abundance of C. cunea did not differ significantly from those of the control. Therefore, Bt-Cry1Ah1 transgenic poplar can be used to effectively control damage by target insect pests without negatively affecting non-target insects and parasitoids.

Molecular Cloning and Characterization of Five Glutathione S-Transferase Genes and Promoters from Micromelalopha troglodyta (Graeser) (Lepidoptera: Notodontidae) and Their Response to Tannic Acid Stress.

Plants accumulate phenolic compounds such as tannic acid to resist insect herbivores. The survival of insects exposed to toxic secondary metabolites depends on the detoxification metabolism mediated by limited groups of glutathione S-transferases (GSTs). Micromelalopha troglodyta (Graeser) (Lepidoptera: Notodontidae) is an important foliar pest of poplar trees. GSTs play an important role in xenobiotic detoxification in M. troglodyta. Five GST genes were identified in M. troglodyta and were classified into five different cytosolic GST classes, delta, omega, sigma, theta, and zeta. Real-time fluorescent quantitative polymerase chain reaction (qPCR) was used to determine the mRNA expression of the five cloned GSTs in the midguts and fat bodies of M. troglodyta. The mRNA expression of the five GSTs was significantly induced when M. troglodyta was exposed to tannic acid. To further understand the tannic acid regulatory cascade, the 5′-flanking promoter sequences of the five MtGSTs were isolated by genome walking methods, and the promoters were very active and induced by tannic acid. In summary, the induction of GST mRNA expression was due to the response of five MtGST promoters to tannic acid. Therefore, MtGST promoters play an important role in the regulation of GST transcription.

Induction Expression of P450 by Tannic Acid in Micromelalopha troglodyta (Lepidoptera: Notodontidae) Larvae

Abstract Cytochromes P450, a gene family generally associated with detoxification, was analyzed by real-time fluorescent quantitative PCR (qRT-PCR) in Micromelalopha troglodyta (Graeser) (Lepidopte...

Overexpression of PtDXS Enhances Stress Resistance in Poplars.

1-Deoxy-d-xylulose-5-phosphate synthase (DXS) is the rate-limiting enzyme in the plastidial methylerythritol phosphate pathway (MEP). In this study, PtDXS (XM_024607716.1) was isolated from Populus trichocarpa. A bioinformatics analysis revealed that PtDXS had high homology with the DXSs of other plant species. PtDXS expression differed among plant tissues and was highest in young leaves and lowest in roots. The recombinant protein was produced in Escherichia coli BL21 (DE3), purified, and its activity evaluated. The purified protein was capable of catalyzing the formation of 1-deoxy-d-xylulose-5-phosphate (DXP) from glyceraldehyde-3-phosphate and pyruvate. A functional color assay in E. coli harboring pAC-BETA indicated that PtDXS encodes a functional protein involved in the biosynthesis of isoprenoid precursors. The treatment of P. trichocarpa seedlings with 200 μM abscisic acid (ABA), 200 mM NaCl, 10% polyethylene glycol6000, and 2 mM H2O2 resulted in increased expression of PtDXS. The ABA and gibberellic acid contents of the transgenic lines (Poplar Nanlin 895) were higher than wild types, suggesting that DXS is important in terpenoid biosynthesis. Overexpression of PtDXS enhanced resistance to S. populiperda infection. Furthermore, the transgenic lines showed decreased feeding by Micromelalopha troglodyta, supporting the notion that PtDXS is a key enzyme in terpenoid biosynthesis.

Tannic Acid Induction of a GlutathioneS-transferase inMicromelalopha troglodyta(Lepidoptera: Notodontidae) Larvae

Abstract Micromelalopha troglodyta (Graeser) (Lepidoptera: Notodontidae) is an important pest of poplar trees, Populus spp. (family Salicaceae), in China. Herein, we report the first cloning and sequencing of a full-length cDNA of a delta class (Class I) glutathione S-transferase (GST), MtGSTd1, from the larval midgut of M. troglodyta. The open reading frame of the MtGSTd1 cDNA was 657 bp and encoded 219 amino acid residues in M. troglodyta. Furthermore, specific activities of GSTs were induced in fat bodies and midguts of M. troglodyta by tannic acid. MtGSTd1 mRNA also was induced by tannic acid in the fat bodies and midguts. GST activities increased following the elevated expression of GST mRNA in M. troglodyta. These findings indicate that the GSTs may have an antioxidant role in the metabolism of plant secondary substances in M. troglodyta larvae.

In vitro inhibition of glutathione S-transferases by several insecticides and allelochemicals in two moth species

Glutathione S-transferases (GSTs) are important detoxification enzymes in insects. This study examined the inhibitory effects of five insecticides (beta-cypermethrin, fenpropathrin, phoxim, abamectin, acetamiprid) and two plant-derived allelochemicals (quercetin, tannic acid) on GST activity in Micromelalopha troglodyta (Graeser) and Clostera anachoreta (Fabricius). GST activities were suppressed by all the insecticides and allelochemicals tested; the two allelochemicals were the most potent inhibitors, reducing GST activity in vitro in a dosage-dependent manner. Kinetic analyses of GST inhibition by quercetin and tannic acid in M. troglodyta and C. anachoreta suggested biochemical differences in their GSTs.

Communication between plants: induced resistance in poplar seedlings following herbivore infestation, mechanical wounding, and volatile treatment of the neighbors

AbstractThe possibility of communication between plants was proposed over 25 years ago, although previous demonstrations have suffered from methodological problems and have not been widely accepted. Micromelalopha troglodyta (Graeser) and Clostera anastomosis (L.) (both Lepidoptera: Notodontidae) are important leaf‐feeding insects on poplars (Populus spp.; Salicaceae). There is no report of M. troglodyta‐ or C. anastomosis‐induced plant–plant communication up to now. To understand the regulatory mechanism of poplar defense responses, the specific activities of the presumed anti‐herbivore enzymes phenylalanine ammonia lyase (PAL), lipoxygenase (LOX), polyphenol oxidase (PPO), and peroxidase (POD) were determined in poplar seedlings treated with herbivore infestation and volatiles, artificially damaged seedlings, and intact healthy poplar seedlings growing nearby. The expression levels of PPO, POD, PAL, and LOX were elevated in poplar seedlings treated by herbivore infestation, mechanical wounding, methyl jasmonate, methyl salicylate, or benzothiazole. Furthermore, plants neighboring the treated poplar seedlings also showed increased expression levels of PPO, POD, PAL, and LOX relative to the control. These induced responses against feeding injury, mechanical wounding, and volatile treatment in expression levels of PPO, POD, PAL, and LOX suggest interplant communication between poplar seedlings.

杨树舟蛾类虫害发生规律与综防技术研究

通过杨树虫害普查，发现为害较严重的舟蛾虫害有杨扇舟蛾、杨小舟蛾、杨二尾舟蛾、栎掌舟蛾、分月扇舟蛾5种。在此基础上，对全市杨树舟蛾虫类为害特点和发生规律进行了详细调查，研究舟蛾类主要害虫生活习性和规律，取食特点，4种药剂筛选试验以及综合防治方法。 According to the poplar pests survey, it is found that more serious diseases were caused by 5 kinds of Notodontidae such as Clostera anachoreta, Micromelalopha troglodyta graeser, Cerura menciana moore, Phalera assimilis and Clostera anastomosis. Based on the above finding, the symptoms and encroaching regu-lation law of Notodontidae on Poplar were investigated. The purpose is to research the life history of Noto-dontidae Pests, encroaching regulation law and the comprehensive means of prevention and management for diseases occurring by selection experiments of 4 kinds of fungicides.

Alteration of glutathione S-transferase properties during the development of Micromelalopha troglodyta larvae (Lepidoptera: Notodontidae)

Micromelalopha troglodyta (Graeser) is an important pest of poplar in China. Glutathione S-transferases (GSTs) are known to be responsible for adaptation mechanisms of M. troglodyta. The activities and kinetic constants of glutathione S-transferases in M. troglodyta were studied. Significant differences in glutathione S-transferase activity and kinetic characteristics were observed among five instars of M. troglodyta larvae. Furthermore, the inhibition of glutathione S-transferase activity in five instars by 24 inhibitors was conducted. The results show the inhibition of GST activity of different instars by 24 inhibitors was different. For GST activity in the 1st instar, chlorpyrifos, lambda-cyhalothrin, endosulfan, abamectin, fipronil and pyridaben were the best inhibitors tested, and for GST activity in the 2nd instar, tannic acid and quercetin were the most potent inhibitors tested, and for GST activity in the 3rd instar, the inhibitory effects of quercetin, chlorpyrifos and lambda-cyhalothrin were the highest, and for GST activity in the 4th instar, quercetin and lambda-cyhalothrin were the best inhibitors, and the inhibitory effect of phoxim was the highest for GST activity in the 5th instar. Our results show that glutathione S-transferases in different instars are qualitatively different in isozyme composition and thus different in sensitivity to inhibitors.

In Vitro Inhibition of the Diphenolase Activity of Tyrosinase by Insecticides and Allelochemicals in Micromelalopha troglodyta (Lepidoptera: Notodontidae)

Tyrosinase is a copper enzyme and plays a key role in normal insect development. We studied the in vitro inhibitory effects of selected insecticides and allelochemicals on the diphenolase activity of tyrosinase in Micromelalopha troglodyta (Graeser) (Lepidoptera: Notodontidae). Two pyrethriods (cyfluthrin and deltamethrin) and 3 other insecticides (hexaflumuron, abamectin and imidacloprid) were the least inhibitory, whereas 5 organophosphates (triazophos, malathion, chlorpyrifos, omethoate and profenofos), 1 carbamate (methomyl), 4 pyrethriods (fenpropathrin, beta-cypermethrin, bifenthrin and lambda-cyhalothrin), 1 organochlorine (endosulfan), 2 allelochemicals (tannic acid and 2-tridecanone) and 4 other insecticides (emamectin benzoate, fipronil, acetamiprid and pyridaben) were moderately inhibitory. Three chemicals (quercetin, phenyl thiourea and phoxim) were the most potent inhibitors of the enzymes among all compounds tested and inhibited the diphenolase activity of tyrosinase in vitro in a dose-dependent manner. Furthermore, phenyl thiourea, phoxim and quercetin showed neither typical competitive nor noncompetitive binding to the substrate, with Ki of 0.13 μM, 49.30 μM and 37.71 μM, respectively.

Tissue Distribution and Properties of Glutathione S-transferases in Micromelalopha troglodyta (Lepidoptera: Notodontidae)

The small prominent, Micromelalopha troglodyta (Graeser) (Lepidoptera: Notodontidae), is an important pest of poplar in China. Glutathione S-transferases are known to be responsible for adaptation mechanisms of M. troglodyta. Thus, the tissue distribution and kinetic constants of glutathione S-transferase activity in the small prominent were studied. Significant differences in glutathione S-transferase (GST) activity and distribution percentages of GST activity and kinetic characteristics were observed among 4 tissues (head, midgut, fat body and integument). Furthermore, the inhibition of glutathione S-transferase activity in 4 tissues by 21 inhibitors was conducted. The results showed the inhibition of GST activity of different tissues by 21 inhibitors is different. For GST activity in heads, chlorpyrifos, profenofos, lambda-cyhalothrin, fipronil and quercetin were the best inhibitors tested. Tannic acid was the most potent inhibitor of midgut GST activity. In the fat body, GST activity was inhibited most by tannic acid, chlorpyrifos and profenofos. The inhibitory effect of profenofos and phoxim was highest for GST activity in the integument. Our results showed that glutathione S-transferases in different tissues are qualitatively different in isozyme composition and thus different in sensitivity to inhibitors.

In vitro Inhibition of Carboxylesterases by Insecticides and Allelochemicals in Micromelalopha troglodyta (Graeser) (Lepidoptera: Notodontidae) and Clostera anastomosis (L.) (Lepidoptera: Notodontidae)

Both Micromelalopha troglodyta (Graeser) and Clostera anastomosis (L.), are important pests of poplar, and usually coexist during the period of poplar growth in China. The carboxylesterases have been recognized to play an important role in the detoxification of xenobiotics in the two Notodontidae species. In vitro inhibitory effects by insecticides and allelochemicals on carboxylesterase activity in M. troglodyta and C. anastomosis were studied. The results showed that three organophosphates (chlorpyrifos, phoxim and profenofos) were the best inhibitors of the enzymes among all compounds tested in M. troglodyta and C. anastomosis. Chlorpyrifos inhibited carboxylesterase activity in M. troglodyta and C. anastomosis to a similar degree, but phoxim and profenofos inhibited to different degrees. Furthermore, kinetic analyses of carboxylesterase inhibition by phoxim, chlorpyrifos and profenofos were also investigated. The results showed that phoxim inhibited carboxylesterase activity with respect to α-naphthyl acetate (α-NA) in a noncompetitive manner in M. troglodyta, while the inhibition of phoxim showed competitive to α-NA in C. anastomosis. The inhibition of chlorpyrifos showed neither typical competitive nor noncompetitive to α-NA both in M. troglodyta and C. anastomosis. Profenofos inhibited carboxylesterase activity with respect to α-NA in a noncompetitive manner in M. troglodyta, while the inhibition of phoxim showed neither typical competitive nor noncompetitive to α-NA in C. anastomosis. These results may contribute to the understanding of the sensitivity difference of M. troglodyta and C. anastomosis to pesticides, and could provide the basis for integrated pest management of the two Notodontidae species.