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Increased expression of the insect control protein genes of Bacillus thuringiensis in Populus has been critical to the development of genetically improved plants with agronomically acceptable levels of insect resistance. Bacillus thuringiensis (Cry1Ah1) proteins with highly specific toxicity against Hyphantria cunea were screened using an indoor bioactivity assay to obtain hyper-resistant transgenic poplars. Then, the Cry1Ah1 sequence was optimized and transformed according to the optimal codon in poplar using software of our own design (http://120.79.60.226:8080/u/chen/w/codonpoplar). A vector was constructed to transform poplar NL895. The Cry1Ah1 gene was transformed to poplar NL895 and six transgenic lines were obtained. The expression and insecticidal effect of the Cry1Ah1 gene in transgenic poplar were evaluated by PCR and ELISA, and the specific indoor activity and field insecticidal activity against H. cunea were compared with a control. We concluded that the insecticidal activity of the transgenic NL895 was significantly better against lower instar larvae of H. cunea than against higher instar larvae. The mortality and pupation rates clearly differed among the various instar larvae and between transgenic and non-transgenic poplar. We obtained poplar seedlings with hyper-resistance to H. cunea by screening Bt genes and optimizing their genetic sequence.

Gut microbiota are important in the adaptation of phytophagous insects to their plant hosts. However, the interaction between gut microbiomes and pioneering populations of invasive insects during their adaptation to new hosts, particularly in the initial phases of invasion, has been less studied. We studied the contribution of the gut microbiome to host adaptation in the globally recognized invasive pest, Hyphantria cunea, as it expands its range into southern China. The southern population of H. cunea shows effective adaptation to Metasequoia glyptostroboides and exhibits greater larval survival on Metasequoia than the original population. Genome resequencing revealed no significant differences in functions related to host adaptation between the two populations. The compatibility between southern H. cunea populations and M. glyptostroboides revealed a correlation between the abundance of several gut bacteria genera (Bacteroides, Blautia, and Coprococcus) and H. cunea survival. Transplanting the larval gut microbiome from southern to northern populations enhanced the adaptability of the latter to the previously unsuitable plant M. glyptostroboides. This research provides evidence that the gut microbiome of pioneering populations can enhance the compatibility of invasive pests to new hosts and enable more rapid adaptation to new habitats., (© The Author(s) 2024. Published by Oxford University Press on behalf of the International Society for Microbial Ecology.)

Chitinases, which are crucial enzymes required for chitin degradation and reconstruction, are often selectively considered to be effective molecular targets for pest control due to their critical roles in insect development. Although the Hyphantria cunea chitinase gene has been reported previously, its sequence characteristics, gene function, and feasibility as a potential target for pest management were absent. In the present study, we characterized the H. cunea chitinase gene and designated it HcCht5. Phylogenic and domain structure analysis suggested that HcCht5 contained the typical chitinase features and was clustered into chitinase group I. Tissue-specific and developmental expression pattern analysis with Real-Time Quantitative PCR (RT-qPCR) showed that HcCht5 was mainly expressed in the integument tissues and that the transcript levels peaked during molting. RNA interference (RNAi)-mediated silencing of HcCht5 caused 33.3% (2 ug) and 66.7% (4 ug) mortality rates after double-stranded RNA (dsRNA) injection. Importantly, the interference efficiency of HcCht5 depended on the injection time of double-stranded RNA (dsRNA), as the pre-molting treatment achieved molt arrest more effectively. In addition, transcriptome sequencing (RNA-seq) analysis of RNAi samples demonstrated silencing of the down-regulated HcCht5 genes related to chitin metabolism and molting hormone signaling, as well as genes related to detoxification metabolism. Our results indicate the essential role of HcCht5 in H. cunea development and detail the involvement of its gene function in the larval molting process.

Fall webworm, Hyphantria cunea Drury (Lepidoptera: Erebidae) is extremely adaptable and highly invasive in China as a defoliator of ornamental and forest trees. To better understand the chemical orientation of this insect towards its host products, we determined the structure and distribution of antennal sensilla of H. cunea by scanning electron microscopy (SEM). The results showed that the male antenna was bipectinate and the female antenna was serrate, and they made of three parts, a scape, a pedicel, and a flagellum of more than 58 flagellomeres. Based on their morphology, sensilla squamiformia, sensilla basiconica, sensilla trichodea (ST1, ST2, ST3), sensilla chaetica, sensilla coeloconica, sensilla styloconica and Böhm bristles were distinguished on the antennae in both sexes. The putative functions of these sensilla also were discussed with reference to their morphology, distribution, and ultrastructure. We expect these results to help develop further electrophysiological investigations aiming to a better understanding of H. cunea olfaction. [ABSTRACT FROM AUTHOR]

In this study, the effects of phenolic compounds such as tannic acid and gallic acid, and heavy metals such as iron, zinc, copper, nickel and cobalt on the last larval stage of the first generation of H. cunea were investigated. The larvae were collected from mulberry and hazelnut trees in the district of Çar°amba, Samsun in 2016. 18 foods in total were prepared; two foods by adding 5% concentration of tannic acid and gallic acid to the artificial diet (dry weight), 5 foods by preparing nickel, zinc, copper, cobalt and iron solutions prepared at 8% concentrations, 10 foods by adding 8% concentrations of heavy metal solutions to 5% concentrations of tannic acid and gallic acid separately, and a control diet. Compared to those fed with control food, the consumption amount of the larvae whose diet contained iron, zinc and copper decreased, whereas it increased in the ones fed with nickel and cobalt containing foods. Pupae weight of the larvae fed with tannic acid and metals added(other than nickel) to it has decreased compared to the larvae in control group. While the amount of pupa protein was the lowest in larvae fed with the food in which both gallic acid and zinc used, it was highest in larvae fed with food containing gallic acid. The pupa lipid amount of the larvae fed with foods supplemented with iron, zinc, copper and cobalt were lower than the control group larvae. The longest development time was observed in the larvae in food groups where iron was added to food alone and tannic acid and iron were added together. The results in this study have shown that the addition of secondary compounds and heavy metals together to the artificial food content may increase toxicity of compounds (synergism) or reduce it (antagonism). [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shenyang Agricultural University is the property of Journal of Shenyang Agricultural University Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Forest Research is the property of Forest Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND Hyphantria cunea is a destructive forest pest. To utilise H. cunea nucleopolyhedrovirus (HcNPV) for biological control, understanding insect‐virus interactions is essential. RESULTS: Four cDNA libraries were constructed from H. cunea larvae (two HcNPV‐infected and two uninfected groups) and 76 004 expressed genes were obtained by next‐generation sequencing. Compared with controls, 272 differentially expressed genes (DEGs) were identified in infected groups, including 162 up‐regulated and 110 down‐regulated genes. Transcription levels of 20 random DEGs were consistent with the Solexa expression profiles obtained by quantitative real‐time PCR. DEGs associated with innate immunity were grouped into several categories, including pattern recognition proteins, heat‐shock proteins, UDP‐glycosyltransferases, cytochrome P450s, antimicrobial peptides and hormonal signalling proteins. Interestingly, up‐regulated host genes included farnesoic acid O‐methyltransferase, two juvenile hormone (JH) binding proteins, and a circadian clock‐controlled protein related to JH regulation. Pathway enrichment analysis indicates that mitogen‐activated protein kinase (MAPK) signalling pathways, key candidate genes and important biological pathways may be associated with molecular modification in H. cunea larvae in response to virus stress. CONCLUSION: These findings provide insight for future research on the molecular mechanisms of HcNPV invasion and anti‐HcNPV mechanisms in H. cunea. A better understanding of gene regulation following HcNPV invasion could help to develop the virus as a bio‐insecticide. © 2018 Society of Chemical Industry A better understanding is necessary for insect‐virus interactions. The transcriptomes of HcNPV‐ and non‐infected H. cunea larvae were constructed for expand our understanding of the molecular mechanisms of HcNPV invasion and could assist biological control applications. [ABSTRACT FROM AUTHOR]

Increased expression of the insect control protein genes of Bacillus thuringiensis in Populus has been critical to the development of genetically improved plants with agronomically acceptable levels of insect resistance. Bacillus thuringiensis (Cry1Ah1) proteins with highly specific toxicity against Hyphantria cunea were screened using an indoor bioactivity assay to obtain hyper-resistant transgenic poplars. Then, the Cry1Ah1 sequence was optimized and transformed according to the optimal codon in poplar using software of our own design (http://120.79.60.226:8080/u/chen/w/codonpoplar). A vector was constructed to transform poplar NL895. The Cry1Ah1 gene was transformed to poplar NL895 and six transgenic lines were obtained. The expression and insecticidal effect of the Cry1Ah1 gene in transgenic poplar were evaluated by PCR and ELISA, and the specific indoor activity and field insecticidal activity against H. cunea were compared with a control. We concluded that the insecticidal activity of the transgenic NL895 was significantly better against lower instar larvae of H. cunea than against higher instar larvae. The mortality and pupation rates clearly differed among the various instar larvae and between transgenic and non-transgenic poplar. We obtained poplar seedlings with hyper-resistance to H. cunea by screening Bt genes and optimizing their genetic sequence. [ABSTRACT FROM AUTHOR]

The fall‐webworm (FWW), Hyphantria cunea, is a highly polyphagous insect pest that is native to North America and distributed in different countries around the world. To manage this insect pest, various control methods have been independently evaluated in the invaded areas. Some of the control methods have been limited to the laboratory and need further study to verify their effectiveness in the field. On the other hand, currently, integrated pest management (IPM) has become a promising ecofriendly insect pest management option to reduce the adverse effect of insecticides on the environment. The development of an IPM for an insect pest must combine different management options in a compatible and applicable manner. In the native areas of the insect pests, there are some recommended management options. However, to date, there is no IPM for the management of the FWW in the newly invaded areas. Therefore, to develop an IPM for this insect pest, compilation of effective management option information is the first step. Thus, believing in the contribution of an IPM to the established management strategies, the chemical, biological, natural enemy, sex pheromone, and molecular studies regarding this insect were reviewed and potential future research areas were delineated in this review study. Therefore, using the currently existing management options, IPM development for this insect pest should be the subject of future research in the newly invaded areas. [ABSTRACT FROM AUTHOR]

BACKGROUND: The international invasive and quarantined defoliating insect Hyphantria cunea Drury (Lepidoptera: Arctiidae) causes huge ecological and economic losses in the world. Furthermore, future climate change may alter the distribution of H. cunea and aggravate the damage. In the present study, we used CLIMEX to project the potential global distribution of H. cunea according to both historical climate data (1961–1990) and future climate warming estimates (2011–2100) to define the impact of climate change. RESULTS: Under the historical climate scenario, we found that H. cunea can survive on every continent, and temperature is the main factor that limits its establishment. With climate change, suitability will increase in middle and high latitude regions, while decrease in the low latitude regions. Moreover, tropic regions will be the most sensitive to climate change impacts for the pest to survive. The impacts of climate change will also increase over time, whether they be positive impacts or negative impacts. CONCLUSION: The projected potential distributions provide a theoretical basis for quarantine and control strategies for the management of this pest in each country. Furthermore, these results provide substantial guidance for studies of the effects of climate change on other major forest pests. © 2018 Society of Chemical Industry To guide pest control strategies, projections of the historical and future potential distribution of Hyphantria cunea were obtained, and the suitability of regions under climate change scenarios was evaluated. [ABSTRACT FROM AUTHOR]

In the present study, the toxicological effects of cytisine on the H. cunea larvae were investigated, and the potential of cytisine as a botanical insecticide through field simulation experiments was evaluated. The results showed that cytisine treatment (0.25–2.5%) exerted significant biotoxic effects on the H. cunea larvae, including diminished weight, disruption of both positive (HcCKS1, HcPLK, HcCCNA) and negative (HcGADD and HcCDKN) regulatory genes associated with larval growth, increased mortality, and heightened oxidative damage (H 2 O 2 and MDA). Cytisine treatment significantly reduced glucose content and inhibited the expression of key rate-limiting enzyme genes (HcPFK , HcPK , HcHK1, HcCS , and HcIDH2) within glycolysis and the tricarboxylic acid cycle pathways. Under cytisine treatment, detoxification enzyme activities (CarE and GST) and expression of detoxification genes (HcCarE1, HcCarE2, HcCarE3, HcGST1, and HcGST3) were inhibited in H. cunea larvae. An increased contents of SOD, CAT, ASA and T-AOC, as well as expression of antioxidant enzyme genes HcSOD1 and HcCAT2 , was found in cytisine-treated H. cunea larvae. Simultaneously, this is accompanied by a significant reduction in the expression of four antioxidant enzyme genes (e.g., HcPOD1 and HcPOD2). In the field experiment, a cytisine aqueous solution (25 g/L) with pre-sprayed and directly sprayed ways demonstrated potent insecticidal activity against H. cunea larvae, achieving a mortality rate of 53.75% and 100% at 24 h, respectively. Taken together, cytisine has significantly weight inhibition and lethal toxicity on the H. cunea larvae, and can be developed as a botanical insecticide for H. cunea control. [Display omitted] • Cytisine treatment exerted significant biotoxic effects on the H. cunea larvae. • Cytisine treatment elicited inhibition of the larval detoxification metabolic system. • Cytisine treatment caused oxidative damage on H. cunea larvae. • Cytisine can be developed as a botanical insecticide for H. cunea control. [ABSTRACT FROM AUTHOR]

A broad survey of the fall webworm (Lepidoptera: Erebidae) populations in agricultural and forested areas in the Central Black Sea Region of Turkey led to the detection of a granulovirus (GV). Hyphantria cunea granulovirus (HycuGV)-Hc1 isolate was characterized and tested against third instar larvae of H. cunea. Electron microscopy confirmed typical GV morphology with ovoid granules of approximately 368 ±  16 nm × 201 ±  19 nm. Each granule contained a single rod-shaped virion with a mean size of 43 ± 12 nm × 250 ± 12 nm. The genome was analyzed by restriction endonuclease and estimated to be ∼112 kb. Partial sequencing of the granulin (gran), late expression factor-8 (lef-8) and late expression factor-9 (lef-9) genes also confirmed the identity of the virus as HycuGV. A phylogenetic analysis based on these conserved genes, HycuGV-Hc1 grouped together with the previous HycuGV isolate (A5-1) and Estigmene acrea granulovirus (EsacGV) isolate from the same family. The LC50 of HycuGV-Hc1 was 2.6 × 104 occlusion bodies (OBs/ml). Pot experiments, under field conditions, showed significant differences between virus treated and control groups. This is the first study to describe a novel Turkish HycuGV-Hc1 isolate, and preliminary data suggests that the virus has a significant potential as an effective biopesticide for control of H. cunea. [ABSTRACT FROM AUTHOR]

Insecticidal effects of Bacillus megaterium isolates maintained from bacterial oozed pupae were studied on pupae and 2nd instar larvae of Hyphantria cunea. The bacterial isolates were identified according to morphological, physiological, biochemical and sequence analyses. This study reported that Bacillus megaterium isolates, HMA5 and BM1, caused different abnormal wings shapes and hair loss on thorax and abdomen of Hyphantria cunea. In addition, the HMA5 and BM1 treated pupae showed significantly reduced ability of adult emergence rates. The percentages of the adult emergence from pupae were 1% and 2% for HMA5 and BM1, respectively. [ABSTRACT FROM AUTHOR]

Chitin deacetylases (CDAs) are enzymes that catalyze the conversion of chitin into chitosan, thereby influence the mechanical and permeability properties of structures such as the cuticle and peritrophic matrices. The full length cDNAs of chitin deacetylase2 (CDA2) genes from Hyphantria cunea were fully cloned by PCR amplification. Two cDNA sequences of HcCDA2 were searched from transcriptome of H. cunea and named as HcCDA2a and HcCDA2b . The deduced protein sequences showed that HaCDA2a and HaCDA2b are synthesized as preproteins of 524 and 518 amino acid residues with an 18-amino acid signal peptide, respectively. HcCDA2a and HcCDA2b contained a chitin-binding domain (ChBD), a low-density lipoprotein receptor class A domain (LDLa) and a polysaccharide deacetylase-like catalytic domain (CDA). Gene expression analyses results showed that HcCDA2a and HcCDA2b were both expressed at the head, integument, foregut, midgut, hindgut, Malpighian tubules and fat body, as well as the 1st to 5th days of fifth instar larvae. Western blot analyses revealed that HcCDA2 protein was highly abundant in the head and integument, and the developmental expression result in the fifth instars showed that HcCDA2 was highly present at the first two days. Besides, RT-PCR results showed that HcCDA2a and HcCDA2b were both expressed in integument and head, whether in molting stage or feeding stage. No visiable phenotypic changes were observed after injection of ds HcCDA2b , while lethal phenotypes of cuticle shedding failure and high mortality were resulted from injection of ds HcCDA2a . The silence of HcCDA2a leads to the ecdysis failure and death of H. cunea . These results suggest that HcCDA2 plays an important role during insect development, and provide new candidate targets and basis for developing environment-friendly pesticides. [ABSTRACT FROM AUTHOR]

Fall webworm, Hyphantria cunea Drury (Lepidoptera: Arctiidae) is extremely adaptable and highly invasive in China as a defoliator of ornamental and forest trees. Both voltinism and diapause strategies of fall webworm in China are variable, and this variability contributes to it invasiveness. Little is known about molecular regulation of diapause in fall webworm. To gain insight into possible mechanisms of diapause induction, high-throughput RNA-seq data were generated from non-diapause pupae (NDP) and diapause pupae (DP). A total of 58,151 unigenes were assembled and researched against nine public databases. In total, 29,013 up-regulated and 3451 down-regulated unigenes were differentially expressed by DP when compared with those of NDP. Genes encoding proteins such as UDP-glycosyl transferase (UGT), cytochrome P450 and Hsp70 were predicted to be involved in diapause. Moreover, GO function and KEGG pathway enrichments were performed on all differentially expressed genes (DEGs) and showed that cell cycle and insulin signaling pathways may be related to the diapause of the fall webworm. This study provides valuable information about the fall webworm transcriptome for future gene function research, especially as it relates to diapause. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The fall webworm, Hyphantria cunea (Drury) (Lepidoptera: Arctiidae), is a major invasive pest in China, where it seriously threatens fruit and ornamental trees and windbreak systems. An auto-contamination trap-strips system was designed to disseminate Beauveria bassiana for biological control. The standard trap consisted of a yellow or green trap with a width no larger than 30 cm and with B. bassiana inside it. Therefore, the trap-strips provided an appropriate microenvironment for the fall webworm to pupate, and an acceptable humidity for B. bassiana to infect and reproduce. The average infection rates of the trap-strips systems were more than 90%. The present study demonstrated a practical application of how physical and biological control of this pest can be conducted efficiently and economically. [ABSTRACT FROM AUTHOR]

Abstract: Heat shock proteins (HSPs) are known to be induced in response to various stress factors. Although HSPs have been studied in a number of insects, not much is known about HSPs in the natural enemies of insects, especially parasitoids. In this study, we identified and characterized five full‐length HSP genes (Cchsp40, Cchsp60, Cchsp70, Cchsp83, and Cchsp90) from an endoparasitic chalcid wasp, Chouioia cunea, which parasitizes the fall webworm, Hyphantria cunea pupae, a worldwide pest. The expression of Cchsps in response to temperature, pesticide stresses and UV radiation were also investigated by quantitative real‐time polymerase chain reaction (RT‐qPCR). The results showed that all five Cchsps were induced in response to hot and cold temperatures. Four pesticides induced the abundant expression of Cchsp70, Cchsp83 and Cchsp90 while ultraviolet radiation up‐regulated Cchsp40, Cchsp70, Cchsp83 and Cchsp90. These results indicate the different transcriptional profiles of the five different Cchsps in response to various abiotic stresses. The findings of this study provide insights into the response of C. cunea to abiotic stresses and insight into the use of this parasitoid in biological control strategies. [ABSTRACT FROM AUTHOR]

Fructose 1, 6-diphosphate (FDP) is an endogenous intermediate in the glycolytic pathway, as well as an allosteric activator of phosphofructokinase (PFK). Based on the role in promoting glycolysis, FDP has been widely used as a therapeutic agent for mitigating the damage of endotoxemia and ischemia/reperfusion in clinical practice. However, the effect of exogenous FDP-induced glycolysis activation on insect carbohydrate metabolism and chitin synthesis remains largely unclear. Here, we investigated for the first time the effects of FDP-Na, an allosteric activator of PFK, on the growth and development of Hyphantria cunea larvae , a serious defoliator in agriculture and forestry, especially on glycolysis and chitin synthesis. The results showed that FDP-Na significantly restrained the growth and development of H. cunea larvae and resulted in larval lethality. After treatment with FDP-Na, hexokinase (HK), phosphofructokinase (PFK) and pyruvate kinase (PK) were significantly activated, and HcHK2 , HcPFK , HcPK were dramatically upregulated, which suggested that FDP-Na enhanced glycolysis in H. cunea larvae. Meanwhile, FDP-Na also distinctly impacted chitin biosynthesis by disturbing transcriptions of genes in the chitin synthesis pathway, resulting in changes of chitin contents in the midgut and epidermis of H. cunea larvae. Therefore, we considered that FDP-Na caused the growth and development arrest, and impacted chitin biosynthesis, probably by disturbing in vivo glycolysis and carbohydrate metabolism in H. cunea larvae. The findings provide a new perspective on the mechanism by which glycolysis regulates insect growth and development, and lay the foundation for exploring the potential application of glycolysis activators in pest control as well. [Display omitted] • FDP-Na caused the growth and development arrest in H. cunea larvae. • Three key rate-limiting enzymes in glycolysis pathway were dramatically activated by FDP-Na. • FDP-Na affected the expression of key genes in the chitin synthesis pathway. • FDP-Na disturbed chitin biosynthesis in the midgut and epidermis of H. cunea larvae. [ABSTRACT FROM AUTHOR]

North America has distinct types of Hyphantria moths (Arctiidae) characterized by red ( RD)- and black ( BL)-headed larvae, of which the taxonomic status is unresolved. Genetic divergence of 26 populations, based on 710 bp of the mt COI sequence, showed two phylogenetic lineages, which could not be connected in the haplotype network with 95% confidence. The two lineages are separated by 3.1% sequence divergence and should be considered for full species status. The estimated split occurred 1.2-1.6 million years ago. The range of the RD type covered most of the continent, whereas that of the BL type was limited to eastern deciduous forests. Several biological characteristics were differentiated in the zone of cohabitation where BL had more annual generations than RD. Spring emergence of BL precedes that of RD in the field by at least 1 month, because the diapause in BL was shallow, whereas it was deep in RD. Voltinism requires discreteness of numbers, which functions as a sink of hybrids between the two parental lines that have distinct but equally adaptive reproductive strategies; BL may be more r-strategist-like and RD more K-strategist-like, because fast-developing BL has multivoltine life cycle, investing less silk proteins as the round-the-clock feeder, and slow-developing RD univoltine one investing more silk as the nocturnal feeder. Also, intensity of diapause, deep in RD and weak in BL, was grossly different, which may enforce segregation of spring adults. Allochronic speciation avoiding coincidental occurrence of adult stages is therefore the most likely scenario. Because the adults never meet in nature, large morphological differentiation is not required. [ABSTRACT FROM AUTHOR]

The fall webworm, Hyphantria cunea (Drury) is a major invasive pest in China. Aminopeptidase N (APN) isoforms in lepidopteran larvae midguts are known for their involvement in the mode of action of insecticidal crystal (Cry) proteins from Bacillus thuringiensis. In the present work, we identified a putative Cry1Ab toxin-binding protein, an APN isoform designated HcAPN3, in the midgut of H. cunea by ligand blot and mass spectrometry. HcAPN3 was highly expressed throughout all larval developmental stages and was abundant in the midgut and hindgut tissues. HcAPN3 was down-regulated at 6 h, then was up-regulated significantly at 12 h and 24 h after Cry1Ab toxin treatment. We expressed HcAPN3 in insect cells and detected its interaction with Cry1Ab toxin by ligand blot assays. Furthermore, RNA interference (RNAi) against HcAPN3 using oral delivery and injection of double-stranded RNA (dsRNA) resulted in a 61-66% decrease in transcript level. Down-regulating of the expression of HcAPN3 was closely associated with reduced susceptibility of H. cunea to Cry1Ab. In addition, the HcAPN3E fragment peptide expressed in Escherichia coli enhanced Cry1Ab toxicity against H. cunea larvae. This work represents the first evidence to suggest that an APN in H. cunea is a putative binding protein involved in Cry1Ab susceptibility. [ABSTRACT FROM AUTHOR]

Chouioia cunea (Yang) (Hymenoptera: Eulophidae) is an indigenous pupal endoparasitoid that effectively attacks the exotic fall webworm Hyphantria cunea (Drury) (Lepidoptera: Arctiidae) in China. In this novel association, the parasitoid's venom has played an important role in subduing the immune defense of the host although little is known about the composition and functions of the parasitoid's venom. We therefore first identified the parasitoid's major venom proteins using electrospray ionization--mass spectrometry (ESI-MS). Approximately 207 different proteins were identified from C. cunea's venom; among them 26 types widely existed in other endoparasitoids' venom, including calreticulin and arginine kinase, which inhibited the host immune system. [ABSTRACT FROM AUTHOR]

Fall webworm, is a quarantine pest, which has caused damage to agricultural and forestry production in China. In this paper, based on the use of maximum entropy method (MaxEnt), we constructed the geographic distribution prediction model of fall webworm. The results show that the accuracy of the prediction model is very high (AUC=0.921), and the distribution is mainly influenced by precipitation of warmest quarter (24.5%), altitude (24.4%), mean temperature of coldest quarter (20.5%), standard deviation of temperature seasonality (9.2%) and temperature annual range (3.7%). The current suitable areas of fall webworm in China are concentrated in the southern northeast China, Beijing-Tianjin-Hebei region and most parts of north China Plain. The common natural characteristics of these areas are: rain heat over the same period, higher relative humidity and no extreme low temperature. In the context of 3 representative concentration pathways (RCPs), the geographic distributions of fall webworm in 2050 share the same variation tendency, though the variation degree differs. There is a tendency of expansion towards the north, with distribution areas in parts of the northeast plain, parts of the Sichuan basin and the north China Plain. The results are conducive to a comprehensive understanding of the current and future distributions of fall webworm, and have theoretical significance for investigating and implementing scientific control tactics for the insect pest of fall webworm. [ABSTRACT FROM AUTHOR]

Climatic data with a high temporal and spatial resolution are invaluable when modelling the potential distribution of non-native pests. The European Commission Joint Research Centre Monitoring Agricultural ResourceS ( MARS) programme provides a unique source of European daily climatic data. Available from 1975 to 2015 and updated annually, the data are interpolated from over 5000 weather stations to 25-km grid cells. All geographical Europe is included, plus Mediterranean areas of the Middle East and North Africa. The climatic parameters available include temperature (daily minima and maxima), solar radiation, rainfall and relative humidity. As well as the potential for use in simple pest models, selected parameters can be imported into more complex models, such as CLIMEX, for more detailed analyses. Case studies showing how the MARS data have been used by the UK in pest risk analyses are presented for three insect pests: Thaumetopoea pityocampa, Hyphantria cunea (both Lepidoptera) and Popillia japonica (Coleoptera). The case studies illustrate some methods of representing uncertainty where thresholds are lacking in the published literature, there are conflicting data and only air temperature data are available to model a soil-dwelling organism. [ABSTRACT FROM AUTHOR]

Sexual discrimination of Hyphantria cunea Drury (Lepidoptera: Erebidae) is very easy through checking male and female antennae of adult moths. Often sexing of insects in pupal stages is also needed. Although weight and size of male and female pupae are quite different, these alone are not enough to distinguish the sexes in every instance. Examining pupae of H. cunea with a binocular microscope reveals differences between the male and female on the posterior ventral surface of the abdomen. The genital slit is located on the anterior edge of the 8th abdominal segment of the female while it is located in the mid-part of the 9th abdominal segment in the male, on the ventral surface. Also, the genital slit is about twofold longer in the female than in the male. [ABSTRACT FROM AUTHOR]

Fall webworm (Hyphantria cunea Durry, Lepidoptera: Arctidae) is an important pest infecting about 600 hosts. It is harmful especially in hazelnut orchards in the Black Sea Region and is becoming epidemic occasionally. It may cause damage in mulberry, cherry, apple, poplar, and willow beside hazelnut in the region. Due to having a polyphagous feeding behavior and a high reproduction power; fall webworm can spread rapidly and make difficult to manage. In the region, currently, mostly chemical control is applied against this pest. Due to adverse effects of the chemical control to the environment and to living organisms, it is inevitable to develop other alternative control methods for this pest. In this study, the effects of some entomopathogenic fungi isolates obtained from Palomena prasina which is another pest in hazelnut production areas, on H. cunea in laboratory conditions. Overall, 1x108 conidia mL-1 of concentration obtained from 2 isolates of Simplicillium lamellicola (TR-01 and TR-02) and 4 isolates of Lecanicillium muscarium (TR-04, TR-05, TR-07 and TR-08) was used against 3rd period larva of the H. cunea. The experiment was conducted with four replications, 10 larvae individuals in each. Mortality of H. cunea were reported daily, over 12 days. At the end of 12th day, among the isolates of entomopathogenic fungi, the TR-05 isolate of the L. muscarium ranked the highest mortality by 93.9% rate. Effect of the other isolates of L. muscarium varied between 72.7% and 90.9%. The TR-01 isolate of the S. lamellicola showed effect of 57.6%, and the TR-02 isolate showed effect of 78.8% mortality. Effects of all the isolates used in the study were differed from the control (P<0.05). Based on LT50 and LT90 values, the most effective isolate was identified as TR-04 (5.64/day and 9.38/day, respectively). It can be concluded that, the isolates of L. muscarium was found quite effective and it could be a promising agent for controlling this pest in the field in the future. [ABSTRACT FROM AUTHOR]

Chitin deacetylases ( CDAs) are critical enzymes required for chitin degradation, which play an important role in modifying the physical properties of insect cuticles and peritrophic matrices. A novel chitin deacetylase gene ( hccda5) was identified from Hyphantria cunea. The recombinant expressed Hc CDA5 protein, containing a chitin deacetylase domain ( CDAD), did not show chitin deacetylase activity, but instead showed a strong chitin-binding activity. Transcriptional analysis using qRT- PCR indicated that hccda5 was mainly expressed in the midgut of H. cunea larvae. Feeding H. cunea larvae with Bt ( Bacillus thuringiensis) Cry1A protein induced its downregulation. The gene of hccda5 was successfully silenced by different ds RNAs in insect cell line ( Spodoptera frugiperda line, Sf9), which provided a tool to study the function of an expressed gene in insect cell line and laid a foundation for RNAi of hccda5 in H. cunea larvae. [ABSTRACT FROM AUTHOR]

We previously demonstrated that ribosomal RNA (rRNA) of Bombyx mori BM-N cells is rapidly degraded upon infection with heterologous nucleopolyhedroviruses (NPVs), including Autographa californica multiple NPV (AcMNPV), Hyphantria cunea MNPV, Spodoptera exigua MNPV and S. litura MNPV, and that this response is triggered by viral P143 proteins. The transient expression of P143 proteins from heterologous NPVs was also shown to induce apoptosis and caspase-3-like protease activation in BM-N cells. In the present study, we conducted a transient expression assay using BM-N cells expressing mutant AcMNPV P143 (Ac-P143) proteins and demonstrated that five amino acid residues cooperatively participate in Ac-P143 protein-triggered apoptosis of BM-N cells. Notably, these five residues were previously shown to be required for triggering rRNA degradation in BM-N cells. As rRNA degradation in BM-N cells does not result from apoptosis, the present results suggest that Ac-P143-triggered rRNA degradation is the upstream signal for apoptosis induction in BM-N cells. We further showed that P143 protein-triggered apoptosis does not occur in S. frugiperda Sf9 or Lymantria dispar Ld652Y cells, indicating that apoptosis induction by heterologous P143 proteins is a BM-N cell-specific response. In addition, the observed induction of apoptosis in BM-N cells was found to be mediated by activation of the initiator caspase Bm-Dronc. Taken together, these results suggest that BM-N cells evolved a unique antiviral system that recognizes heterologous NPV P143 proteins to induce rRNA degradation and caspase-dependent apoptosis. [ABSTRACT FROM AUTHOR]

Constitutive chemical defenses play important roles in protecting trees against insects. Studying the constitutive chemical resistance of trees to insect would thus help control the pests and minimize the associated ecological and economic losses. Poplar is an ecologically and economically important tree species but has been greatly damaged by fall webworm ( Hyphantria cunea ) in China. Here we investigated H. cunea resistance in 7 poplar cultivars commonly planted in China by applying bioassays, and analyzed metabolic profiles of H. cunea -resistant and -susceptible cultivars. Substantial variation in chemical profiles between resistant and susceptible genotypes was detected. Ninety-two distinguishing metabolites were identified. Correlation analysis indicated that hydroxycinnamates, benzenoids and their derivatives significantly positively correlated with resistance against H. cunea , whereas sucrose, glutamic acid and myo-inositol showed negative correlations. Bioassays of H. cunea given an artificial diet supplemented with these compounds confirmed their effects but indicated that they each have different roles. Metabolite enrichment and gene expression analysis showed that phenylpropanoid biosynthesis in poplar is important for constitutive resistance against H. cunea . Induced experiment found that some of the constitutive resistance-related metabolites were induced by H. cunea indicating that these metabolites also play a role in induced resistance. This study provides further insight into the molecular mechanisms behind H. cunea resistance in poplar and suggests candidate metabolites that may serve as biomarkers for breeding of resistant poplar cultivars. [ABSTRACT FROM AUTHOR]

In tritrophic ‘plants–herbivores–natural enemies’ systems, there are relatively few reports concerning the role(s) of kairomones in pupal parasitism. Chouioia cunea Yang (Hymenoptera: Eulophidae), an endoparasitic chalcid wasp, parasitizes pupae of the fall webworm (Hyphantria cunea Drury). The role of host-related kairomones was investigated using electroantennogram (EAG) and behavioral techniques. Chemicals from some host stages (pupae) and host by-products (frass), induced arrestment behavior of female parasitoids, while chemicals from prepupae, were inactive. Gas chromatography–mass spectrometry analysis of volatiles collected from pupae, frass and prepupae using solid-phase microextration revealed seven compounds with carbon chain lengths ranging from C4 to C20. All of the chemicals elicited significant EAG responses in C. cunea. Y-tube olfactometer bioassays demonstrated a significant positive response of mated female C. cunea to 1-dodecene. These data provide a better understanding of the host location mechanisms of pupal parasitoid. [ABSTRACT FROM AUTHOR]

Hyphantria cunea (Drury) (Lepidoptera: Arctiidae) is an important forest insect pest around the world. It attacks a variety of broad-leaf trees. It has caused serious economic and ecological damage to its new habitats. A mixture of Bt and chlorbenzuron has a higher toxicity and faster killed than those of either agent alone to the 4th instar larvae of H. cunea both by the lab and field test results, and the toxic effect of the mixture treatment was significantly enhanced. Using proteomics technology, including SDS-PAGE and MALDI-TOF-TOFMS, we analyzed differentially expressed proteins of the peritrophic membrane (PM) of the 4th instar larvae of H. cunea, which were treated with the mixture. We identified 91 significantly differentially expressed proteins of the PM of the 4th instar larvae of H. cunea and those proteins were found to be involved in different metabolic pathways and processes. The energy-related and structural proteins made up the largest proportion of all of the identified proteins, and the mixture treatment of proteins was the small proportion of the identified structural proteins and energy-related proteins among the Bt, chlorbenzuron, and mixture treatments. Based on the proteomic data, we found that some proteins and their corresponding functions and pathways were related to the lethal mechanisms observed in 4th instar larvae of H. cunea when treated by the mixture. [ABSTRACT FROM AUTHOR]

Chlorbenzuron is a kind of benzoylphenylureas (BPUs), which plays a broad role in insect growth regulators (IGRs), with an inhibitory effect on chitin biosynthesis. However, BPUs how to regulate glycolysis and insect growth remains largely unclear. Here, we investigated the effects of chlorbenzuron on growth, nutritional indices, glycolysis, and carbohydrate homeostasis in Hyphantria cunea , a destructive and highly polyphagous forest pest, to elucidate the action mechanism of chlorbenzuron from the perspective of energy metabolism. The results showed that chlorbenzuron dramatically restrained the growth and nutritional indices of H. cunea larvae and resulted in lethality. Meanwhile, we confirmed that chlorbenzuron significantly decreased carbohydrate levels, adenosine triphosphate (ATP), and pyruvic acid (PA) in H. cunea larvae. Further studies indicated that chlorbenzuron caused a significant enhancement in the enzyme activities and mRNA expressions of hexokinase (HK), phosphofructokinase (PFK), and pyruvate kinase (PK), resulting in increased glycolytic flux. Expressions of genes involved in the AMP-activated protein kinase (AMPK) signaling pathway were also upregulated. Moreover, chlorbenzuron had remarkable impacts on H. cunea larvae from the perspective of metabolite enrichment, including the tricarboxylic acid (TCA) cycle and glycolysis, indicating an energy metabolism disorder in larvae. The findings provide a novel insight into the molecular mechanism by which chlorbenzuron abnormally promotes glycolysis and eventually interferes with insect growth and nutritional indices. [Display omitted] • The growth and nutritional indices of H. cunea larvae was dramatically arrested by chlorbenzuron. • Chlorbenzuron promoted glycolysis by enhancing activities of HK, PFK and PK. • Chlorbenzuron decreased carbohydrate, ATPand PA levels in H. cunea larvae. • Chlorbenzuron inhibited growth and nutritional indices of H. cunea larvae by downregulating genes related to AMPK. [ABSTRACT FROM AUTHOR]

The release of volatile β-ocimene induced by Hyphantria cunea (H. cunea) larvae in mulberry is an important olfactory cue for host localization of H. cunea adults. In the present study, we demonstrated that H. cunea adults sensitively recognized β-ocimene through a Y-tube test and single sensillum recording (SSR) experiments. Through a combination of homology alignment, tissue profile expression, and transgenic Drosophila SSR assays, HcunOR31 was identified as the specific odorant receptor for β-ocimene in H. cunea. We used transmembrane domain prediction, molecular docking, and peptide synthesis techniques to fabricate three odorant receptor-derived peptide sensors (ORP-sensors) that had the potential to monitor β-ocimene. Among these three, the best sensitivity and specificity to β-ocimene were demonstrated by the ORP3-sensor. Further experimentation revealed that the detection limit of the ORP3-sensor could be as low as one larva feeding on mulberry leaves; in addition, the sensor showed a larger resistance change with the increase in the number of larvae. These findings address the application value of insect olfactory mechanisms and provide an entry point for real-time monitoring of the early occurrence of H. cunea larvae in woodlands. • The specific odorant receptor to the herbivore-induced plant volatile β-ocimene of Hyphantria cunea was characterized. • The fabricated ORP-sensors enabled detection of gaseous β-ocimene at concentration of 1 ppb with excellent selectivity. • The fabricated ORP-sensor could detect β-ocimene released by mulberry leaves feeding on a single larva H. cunea in real time. • The ORP-sensor had potential applications for monitoring the early occurrence of H. cunea larvae. [ABSTRACT FROM AUTHOR]

Phenoloxidase (PO) is a key factor in insect immunity. On invasion of microorganisms and pathogens, prophenoloxidase changes to its active form to PO. This study investigated purification biochemical properties of PO from the hemolymph of 5th instar larvae of Hyphantria cunea (Lepidoptera). The purification fold was determined as 9.67 with a recovery of 0.12 and a specific activity of 23.28 U/mg protein identified. Kinetic parameters of purified PO from the insect H. cunea were determined. The Michaelis constant (Km) and the maximal velocity (Vmax) were 4.08 and 12.98 μmol/min/mg protein, respectively. The optimal pH and temperature of the enzyme for oxidation of L-DOPA were 10.0 and 35 ºC, respectively. The ions Zn2+, Cu2+, K+ and Na+ significantly increased the enzyme activity and synthetic inhibitors such as diethyldithiocarbamate (DETC) significantly decreased it. Finally, it was found that purified PO had a molecular mass of 33 kDa. This study demonstrated some PO properties and its inhibitory effects demonstrating that it can be employed as useful methods for developing novel insecticides to replace traditionally used ones.

Haemocytes of two lepidoptrans Hyphantria cunea (Drury) and Glyphodes pyloalis Walker were studied using light microscopy. Based on available literature, six types of haemocytes were recognized of each species: prohaemocyte, plasmatocyte, granulocyte, oenocyte, spherulocyte and adipohaemocyte. In general, haemocytes in G. pyloalis were smaller than those of H. cunea. This difference were quiet obvious in prohaemocytes and spherulocytes. Differential haemocyte counts showed the granulocytes and plasmatocytes to be the most abundant haemocytes and were recorded 27 and 23 percent for G. pyloalis, and also 28 and 36 percent for H. cunea, respectively. Total haemocyte count were also worked out that was 1800 ± 0.081 cells/mm3 for G. pyloalis and 3013.3 ± 413 cells/mm3 for H. cunea. While bringing about major structural changes to important cell types i.e. plasmatocytes and granulocytes, the juvenile hormone I (JH I) in 0.004 μL/Larva on topical application induced significant changes in total and differential counts compared to controls.

The fall armyworm, Hyphantria cunea Drury (Lepidoptera: Arctiidae) is an insect native to NorthAmerica that was recently introduced into Iran resulting in severe damage to trees and agriculturalproduction. An experiment was conducted to examine potential effects of medicinal plants, Artemisiaannua and Lavandula stoechas and the insect pathogenic bacterium Bacillus thuringiensis var.kurstaki on activities of digestive enzymes (α-amylase, α- and β-glucosidase, lipase and proteases)and lactate dehydrogenase (LDH) in H. cunea by using two hosts, mulberry and sycamore. Resultsshowed that B. thuringiensis var. kurstaki and plant extracts when administered orally, affected thedigestive enzyme profiles of H. cunea. Combined effect of B. thuringiensis, A. annua and L. stoechasextracts on mulberry decreased the activities of digestive enzymes in a dose-related manner, exceptfor β-glucosidase and lipase. When larvae were treated by different concentrations of the mentionedinsecticides, LDH activity increased i.e. the higher activity was obtained by B. thurengiensis alone andB. thurengiensis and L. stoechas extracts together. The least activity was observed in the case of L.stoechas extracts alone on both hosts. Physiological analysis would be particularly informative whenusing combination of biopesticides to enhance the efficiency of a safe management process.

The steroid hormone 20-hydroxyecdysone (20E) has been described to regulate fat body lipid metabolism in insects, but its accurate regulatory mechanism, especially the crosstalk between 20E-induced lipid metabolism and gluconeogenesis remains largely unclear. Here, we specially investigated the effect of 20E on lipid metabolism and gluconeogenesis in the fat body of Hyphantria cunea larvae, a notorious pest in forestry. Lipidomics analysis showed that a total of 1 907 lipid species were identified in the fat body of H. cunea larvae assigned to 6 groups and 48 lipid classes. The differentially abundant lipids analysis showed a significant difference between 20E-treated and control samples, indicating that 20E caused a remarkable alteration of lipidomics profiles in the fat body of H. cunea larvae. Further studies demonstrated that 20E accelerated fatty acid β-oxidation, inhibited lipid synthesis, and promoted lipolysis. Meanwhile, the activities of pyruvate carboxylase, phosphoenolpyruvate carboxykinase, fructose-1,6-bisphosphatase, and glucose-6-phosphatase were dramatically suppressed by 20E in the fat body of H. cunea larvae. As well, the transcriptions of genes encoding these 4 rate-limiting gluconeogenic enzymes were significantly downregulated in the fat body of H. cunea larvae after treatment with 20E. Taken together, our results revealed that 20E disturbed fat body lipid homeostasis, accelerated fatty acid β-oxidation and promoted lipolysis, but negatively regulated gluconeogenesis in H. cunea larvae. The findings might provide a new insight into hormonal regulation of glucose and lipid metabolism in insect fat body., (© 2022 Institute of Zoology, Chinese Academy of Sciences.)

Digestive physiology mediates the adaptation of phytophagous insects to host plants. In this study, the digestive characteristics of Hyphantria cunea larvae feeding preferences on different host plants were investigated. The results showed that the body weight, food utilization, and nutrient contents of H. cunea larvae feeding on the high-preference host plants were significantly higher than those feeding on the low-preference host plants. However, the activity of larval digestive enzymes in different host plants presented an opposite trend, as higher α-amylase or trypsin activity was observed in the group feeding on the low-preference host plants than that feeding on the high-preference host plants. Upon treatment of leaves with α-amylase and trypsin inhibitors, the body weight, food intake, food utilization rate, and food conversion rate of H. cunea larvae significantly decreased in all host plant groups. Furthermore, the H. cunea comprised highly adaptable compensatory mechanisms of digestion involving digestive enzymes and nutrient metabolism in response to digestive enzyme inhibitors. Taken together, digestive physiology mediates the adaptation of H. cunea to multiple host plants, and the compensatory effect of digestive physiology is an important counter-defense strategy implemented by H. cunea to resist plant defense factors, especially the insect digestive enzyme inhibitors.

Background: The fall webworm, Hyphantria cunea, an invasive forest pest found worldwide, causes serious ecological and economic damage. Currently, the application of chemical pesticides is the most widely used strategy for H. cunea management. However, long-term pesticide use leads to pest resistance, phytotoxicity, human poisoning, and environmental deterioration. RNA interference (RNAi) technology may provide an environmentally friendly and cost-effective option for H. cunea control. However, effective RNAi targets and application methods for H. cunea are lacking., Results: We screened and obtained two highly effective RNAi targets, vATPase A (V-type proton ATPase catalytic subunit A) and Rop (Ras opposite), from 23 candidate genes, using initial and repeat screening tests with the double-stranded RNA (dsRNA) injection method. RNAi against these two genes was effective in suppressing each target messenger RNA level and interfering with larval growth, leading to significant larval mortality and pupal abnormality. For massive production of dsRNA and practical application of RNAi technology in H. cunea, transformed bacteria expressing dsRNAs of these two genes were prepared using the L4440 expression vector and HT115 strain of Escherichia coli. Oral administration of bacterially expressed dsRNA targeting vATPase A and Rop genes showed high mortality and the same malformed phenotype as the injection treatment. To further investigate the lethal effects of targeting these two genes on larval development, transcriptome sequencing (RNA-seq) was performed on RNAi samples. The results demonstrated disorders in multiple metabolic pathways, and the expression levels of most genes related to insect cuticle metabolism were significantly different, which may directly threaten insect survival. In addition, some new findings were obtained via RNA-seq analysis; for example, the progesterone-mediated oocyte maturation and oocyte meiosis processes were significantly different after silencing vATPase A, and the insect olfactory protein-related genes were significantly downregulated after dsHcRop treatment., Conclusion: vATPase A and Rop are two highly effective RNAi-mediated lethal genes in H. cunea that regulate insect growth via multiple metabolic pathways. Oral delivery of bacterially expressed dsRNA specific to vATPase A and Rop can potentially be used for RNAi-based H. cunea management. This is the first study to apply bacteria-mediated RNAi for the control of this invasive pest, which is a major step forward in the application of the RNAi technology in H. cunea. © 2022 Society of Chemical Industry., (© 2022 Society of Chemical Industry.)

The American white webworm, Hyphantria cunea Drury, was reported from the Guilan province in 2002. Due to its economic importance in the north of Iran, its biology, population fluctuation, host plants and other life characteristics were studied in Rezvanshahr (Guilan) in 2003 and 2004. The larvae feed on a wide range of forest trees, orchards, crops and weeds. The pest had two generations per year and overwintered as pupae in cocoons mostly under tree barks, fences and a few in the soil. The adults were appeared in mid spring and mated 2-3 days after emergence. Females laid their eggs in a cluster underside of host leaves. The maximum number of eggs laid in laboratory and field conditions was 1053 (490.4 ± 86.47) and 1500 (758.85 ± 79.10) per cluster respectively. In optimum conditions (23 ± 1°C and 60-70 % RH and 16L: 8D), the eggs hatched within 7-9 days (7.29 ± 0.22). The first and second larval instars fed gregariously in their nested webs on the leaves where the eggs were deposited. The pest had five larval instars and each larval instar lasted 4-6 days (4.26 ± 0.31). The third and fourth instars left their nests and made webs on other leaves. The pupal stage lasted 10 days in first generation and 9 months in second generation as overwintering pupae.

Aim To establish patterns of genetic variation associated with the well-documented history of invasion and expansion of the fall webworm ( FWW), Hyphantria cunea, into China. Patterns are expected to be affected by geographical and environmental factors as well as a history of control campaigns. Location Northern and eastern China. Methods We genotyped 18 polymorphic microsatellite loci derived from 657 individuals (25 populations) collected from across the distribution range of FWW in China and a native population in USA, and we also sequenced mitochondrial DNA from a subset of 70 individuals. Population genetic structure was analysed by using three Bayesian cluster methods ( structure, geneland and tess) and a multivariate principal component analysis ( PCA). The scenarios of invasion history were tested using an approximate Bayesian computation ( ABC) approach. A multiple matrix regression was performed to assess the relative contributions of geographical and environmental isolation. Results The average allelic richness and mitochondrial haplotype diversity of the FWW populations in China was very low compared to native populations from USA, pointing to a significant bottleneck during colonization. Based on the nuclear markers, two genetically separated groups were identified along with a contact zone between them. ABC analyses suggested a single introduction into the east with subsequent westward expansion. Geographic distance was more important than environmental distance in contributing to genetic differentiation, and geographical barriers were likely to have restricted gene flow, with the contact zone occurring in a mountainous area. Main conclusions The combination of genetic data and historical records of the expansion suggests that geographical barriers and control campaigns have affected the formation and persistence of the two genetic groups. Our study points to ways in which genetic differentiation can develop rapidly in an invasive species after its introduction. [ABSTRACT FROM AUTHOR]

Hyphantria cunea (Drury) (Lepidoptera: Arctiidae) is an invasive insect pest which, in China, causes unprecedented damage and economic losses due to its extreme fecundity and wide host range, including forest and shade trees, and even crops. Compared to the better known lepidopteran species which use Type-I pheromones, little is known at the molecular level about the olfactory mechanisms of host location and mate choice in H. cunea, a species using Type-II lepidopteran pheromones. In the present study, the H. cunea antennal transcriptome was constructed by Illumina Hiseq 2500TM sequencing, with the aim of discovering olfaction-related genes. We obtained 64,020,776 clean reads, and 59,243 unigenes from the analysis of the transcriptome, and the putative gene functions were annotated using gene ontology (GO) annotation. We further identified 124 putative chemosensory unigenes based on homology searches and phylogenetic analysis, including 30 odorant binding proteins (OBPs), 17 chemosensory proteins (CSPs), 52 odorant receptors (ORs), 14 ionotropic receptors (IRs), nine gustatory receptors (GRs) and two sensory neuron membrane proteins (SNMPs). We also found many conserved motif patterns of OBPs and CSPs using a MEME system. Moreover, we systematically analyzed expression patterns of OBPs and CSPs based on reverse transcription PCR and quantitative real time PCR (RT-qPCR) with RNA extracted from different tissues and life stages of both sexes in H. cunea. The antennae-biased expression may provide a deeper further understanding of olfactory processing in H. cunea. The first ever identification of olfactory genes in H. cunea may provide new leads for control of this major pest. [ABSTRACT FROM AUTHOR]

Hyphantria cunea (Drury) is an invasive pest of Morus alba L. in China. β-ocimene and cis-2-penten-1-ol among eleven electro-physiologically active leaf volatiles from M. alba have been reported to influence captures of Hyphantria cunea moths when added into sex pheromone traps. This study further investigated influences of volatile types and their dosages on the electro-physiological responses in the antennae of male and female moths, as well as on mating and oviposition behaviors. Females were, regardless of dosages, more sensitive to β-ocimene and cis-2-penten-1-ol in electro-physiological response tests than males. For males, a dose response was detected, i.e., a dosage of 10 µg and 100 µg of either chemical stimulated higher electric response in their antennae than 1 µg. Moth pairs either exposed respectively to a herbivore-induced M. alba volatile blend (HIPV), to a mechanically-damaged M. alba volatile blend (MDV), to β-ocimene, to cis-2-penten-1-ol, or to pentane as a control showed that pairs exposed to β-ocimene most likely mated, followed by HIPV blends and least by the other volatiles or the control. In contrast, β-ocimene induced about 70% of the female oviposition behaviors and was nearly 4.5 times the oviposition rate than cis-2-penten-1-ol and 2 times than the control. However, none of the chemicals had any effect on the 48 h fecundity or on egg sizes. In conclusion, β-ocimene from mulberry plants alone could promote mating and oviposition in H. cunea at a dosage of 1 mg. The results indicate that reproductive behaviors of H. cunea moths can be enhanced through HIPV blends and β-ocimene induced by feeding of larvae. This contra phenomenon has revealed a different ecology in this moth during colonizing China as local pests would commonly be repelled by herbivore induced chemicals. These chemicals can be used for the development of biological control approaches such as being used together with sex pheromone traps. [ABSTRACT FROM AUTHOR]

Ginkgo biloba is a typical relic plant that rarely suffers from pest hazards. This study analyzed the pattern of G. biloba pest hazards in Beijing; tested the antifeedant activity of G. biloba extracts, including ginkgo flavonoids, ginkgolide, and bilobalide, against Hyphantria cunea larvae; determined the activities of glutathione transferase (GSTs), acetylcholinesterase (AChE), carboxylesterase (CarE) and mixed-functional oxidase (MFO), in larvae after feeding on these G. biloba secondary metabolites; and screened for effective botanical antifeedants in the field. In this study, no indicators of insect infestation were found for any of the examined leaves of G. biloba; all tested secondary metabolites showed significant antifeedant activity and affected the activity of the four larval detoxifying enzymes. Ginkgolide had the highest antifeedant activity and the most significant effect on the detoxifying enzymes (P<0.05). Spraying leaves with G. biloba extracts or ginkgolide both significantly repelled H. cunea larvae in the field (P<0.05), although the former is more economical and practical. This study investigated the antifeedant activity of G. biloba secondary metabolites against H. cunea larvae, and the results provide new insights into the mechanism of G. biloba pest resistance. This study also developed new applications of G. biloba secondary metabolites for effective pest control. [ABSTRACT FROM AUTHOR]

This study explores the feasibility of incorporating public participatory field data collection into satellite-based fall webworm (Hyphantria cuneaDrury) monitoring. Case studies were conducted through fall webworm monitoring at Jinghai county in the north of China and Lieshan county in the middle-east of China. Sample data generated from participatory monitoring data were used for satellite-based fall webworm defoliation mapping, achieving an average accuracy above 92%. By comparing participatory monitoring data with expert measurements, Willmott’s indices of agreement were greater than 0.88, which demonstrated that infestation data collected by local community could achieve a comparable accuracy to expert value. Meanwhile, the comparison with satellite data confirmed that participatory monitoring data could serve as a valuable, high temporal and spatial resolution data source complementary to satellite data, to help forest managers, planners and scientists to better understand the status of fall webworm infestation. [ABSTRACT FROM AUTHOR]