Search Results (123)

Population models offer insights into both theoretical and practical aspects of insect population dynamics. Among the models, stage-structured matrix models are used to describe the population dynamics of insects because the development of insects is by nature stage-structured. Field populations of the pine caterpillar, Dendrolimus spectabilis (Lepidoptera: Lasiocampidae) were monitored in a pine stand located in Dorak-ri, Cheongsan-myeon, Wando-gun, Jeollanam-do, from May 1998 to March 1999, and the pest density was measured as the number of larvae, pupae, or eggs at one-month intervals, excluding the winter season. Life tables and matrix models were constructed based on field observations, and the most vulnerable life stage was identified through sensitivity analysis. The density of the pine caterpillar (number per 1000 cm² branch) was 7.9 on 8 May 1998, and subsequently decreased to 0.5 on 14 March 1999, showing a decreasing trend of caterpillar density. The population growth rate was 0.74, a decreasing trend. The most vulnerable stages were (1) the larvae immediately after hatching and (2) again during overwintering, probably due to indirect mortality caused by humid conditions and activities of natural enemies during winter. Given the significant damage caused by mature larvae in the spring and that the density of the caterpillar after overwintering typically remains stable, forest management requires that the pest density be monitored soon after overwintering to allow decisions about control measures to be taken. Our results showed that a matrix model is useful to describe the population dynamics of the pine caterpillar and to construct suitable management strategies. Full article

Olfactory perception depends on soluble proteins in the perireceptor environment that support odorant transport, mucosal protection, and tissue homeostasis. In insects, odorant-binding proteins (OBPs) in the sensillum lymph are indispensable for odor detection, whereas in humans the indispensability of OBPs (OBP2A/2B) remains unclear because they are inconsistently detected in nasal mucus. Consequently, it remains unclear whether other soluble proteins compensate for this function or how they contribute to odorant processing and signal transmission within the olfactory mucus. Accumulating evidence indicates that OBP-like lipocalins (LCN1, LCN2, LCN15) and apolipoprotein D, together with bactericidal/permeability-increasing (BPI)-fold proteins, act as major mediators of odorant solubilization, antimicrobial defense, oxidative stress regulation, and extracellular matrix (ECM) remodeling. Alterations in those proteins and ECM organization are linked to idiopathic and age-related smell loss, chronic rhinosinusitis, and neurodegenerative disorders, underscoring their broad relevance at the interface of chemosensation, mucosal defense, and brain health. Major unresolved issues include the functional indispensability of human OBPs, the receptor-specific contributions of OBP-like proteins, and the mechanistic relationships linking olfactory proteome remodeling, sensory signaling, and disease progression. This review provides an integrative overview of structural and mechanistic insights, highlights current controversies, and proposes future research directions, including receptor–protein mapping, integrated structural–functional studies, structural–functional analysis of OBP–ECM networks, and clinical validation of OBP-related biomarkers. Full article

This review examines the nutritional and functional potential of Acheta domesticus, the impact of fermentation on its biochemical and microbiological properties, and its application in food ingredients and products. Relevant literature was reviewed on the composition, fermentation behavior, product development, and consumer perceptions related to cricket-based ingredients, with a focus on fermented applications and microbiota interaction. Fermentation improves the safety, digestibility, flavor, and nutritional value of cricket powder. Lactic acid bacteria (e.g., Lactiplantibacillus plantarum and Latilactobacillus curvatus) enhanced substrate acidification, reduced biogenic amines and acrylamide levels, and contributed to desirable volatile compounds production. Additionally, fermentation using yeasts like Yarrowia lipolytica and Debaryomyces hansenii resulted in the production of antimicrobial substances, reduction in chitin, and an increase in the matrix digestibility. Fermented cricket-based ingredients have been successfully applied to bread, biscuits, yogurt, and beverages. Protein hydrolysates produced by fermentation exhibited antioxidant, anti-aging, and preservative properties, expanding potential beyond food. Consumer acceptance was highest when insects were integrated into familiar and visually unobtrusive food formats. To conclude, A. domesticus shows great promise as a sustainable and functional food ingredient. Fermentation offers a key strategy to overcome safety, sensory, and acceptability barriers. Full article

The invasive sap-feeding pest Toumeyella parvicornis (pine tortoise scale) is rapidly spreading across Europe, threatening pine ecosystems, particularly in forest–urban areas of Italy. In this scenario, early detection and monitoring strategies are critical to prevent new outbreaks and mitigate impacts in infested regions. Current surveillance is challenged by the lack of rapid, sensitive tools for indirect detection of this cryptic, canopy-dwelling pest, despite advancements in molecular diagnostics and environmental DNA (eDNA). Here, we established a highly specific qPCR assay using LNA probe chemistry for detecting T. parvicornis DNA from both adult insects and their excreted honeydew. DNA was successfully isolated/quantified from all tested matrices. We recorded average Cq values of 20.9 for insect specimens and 30.3 for collected honeydew samples. Targeting the COI barcoding region, the assay demonstrated excellent specificity in both in silico and in vitro tests, showing no cross-reactivity to other pine-associated taxa. The limit of detection for DNA isolated from insect was 64 fg/µL. This is the first diagnostic protocol to use honeydew as a matrix for indirect detection of T. parvicornis. Optimized for routine application by Plant Health Services, this eDNA-based tool offers a valuable approach for future monitoring of sap-sucking hemipterans in multiple environments. Full article

Chitin synthase (CHS) is essential for maintaining exoskeletal integrity and environmental adaptability in insects. CHS genes are categorized into two types, CHS1 and CHS2. Hemipteran insects possess only the CHS1 gene due to the absence of a peritrophic matrix (PM) in their midgut. However, the identification and functional characterization of the CHS1 gene in Pentatomidae species have not been reported. This study reports the first identification of a CHS gene, ArmaCHS1, from the predatory stink bug, Arma chinensis, and investigates its role in response to temperature stress. The ArmaCHS1 open reading frame spans 4407 bp, encoding a protein of 1468 amino acids, with 14 transmembrane helices and seven N-glycosylation sites. Phylogenetic analysis confirmed its classification within the CHS1 clade, closely related to CHS1 from Halyomorpha halys. qRT-PCR analysis revealed that ArmaCHS1 is predominantly expressed in the exoskeleton and displays developmentally regulated expression (lowest in eggs, highest in adults). Temperature stress experiments demonstrated that ArmaCHS1 expression was significantly upregulated at low temperatures (12 °C, 19 °C) and markedly downregulated at high temperatures (33 °C, 40 °C). These findings indicate that ArmaCHS1 likely contributes to thermal adaptation in A. chinensis by modulating chitin biosynthesis, providing new insights into the environmental stress responses of beneficial predatory insects. Full article

Chitosan is a natural biopolymer with intrinsic antimicrobial properties and strong metal ion chelating properties, making it an ideal matrix for the development of bioactive composites. In this study, silver and copper nanoparticles were synthesized using laser ablation in liquid (LAL) by the ablation of metallic targets into commercial chitosan (Cs) and chitosan produced from Hermetia illucens pupal exuviae (CsE) solutions, avoiding the use of chemical precursors or stabilizing agents. The nanocomposites obtained were characterized by UV–vis spectroscopy, TEM microscopy and FTIR spectroscopy in order to evaluate the size of the nanoparticles and the interactions between the polymer and metal nanoparticles. Antibacterial tests demonstrated the efficacy of Ag-based composites with a minimum inhibitory concentration (MIC) of 0.006 g/L, and Cu-based composites with a MIC of 0.003 g/L against both Escherichia coli and Micrococcus flavus. While the silver composites show antibacterial activity in both colloidal and film forms, the copper composites present antibacterial activity only in colloidal form. Swelling tests indicated that all films maintained a high water absorption capacity, with a swelling index over 200%, unaffected by nanoparticle integration. The results highlight the potential of LAL-synthesized metal–chitosan composites, particularly those based on insect chitosan, as sustainable and effective antimicrobial materials for biomedical and environmental applications. Full article

This study aims to foster a guideline for sustainable supply chain management for edible insect production through a comprehensive review and critical analysis of the current situation, focusing especially on Thailand’s perspective. It addresses the traditional culture and modern practice of insect consumption and how these factors affect current production for commercial purposes. The advantages of nutritional values and farming with edible insects over traditional livestock farming are highlighted. A threats, opportunities, weaknesses, and strengths (TOWS) matrix analysis, producing action-oriented strategies, was based on an analysis of the strengths, weaknesses, opportunities, and threats (SWOT) of Thailand’s edible insect industry. The strategies include enhancement of production and product quality, innovation of intelligent production techniques and agriculture, fortification of branding and product development, encouragement of research and development investment, and the promotion of local product identity. The analysis emphasizes the value of sustainable supply chain management and advocates for the advancement of the bio-circular green (BCG) economy strategy for the edible insect industry. It also emphasizes the importance of stakeholder collaboration and implementing regulations to ensure food safety and sustainable production. Full article

A method for configuration synthesis of a reconfigurable decoupled parallel mechanical leg is proposed. In addition, a configuration evaluation index is proposed to evaluate the synthesized configurations and select the optimal one. Kinematic analysis and performance optimization of the selected mechanism’s configuration are carried out, and the motion mode of the robot’s reconfigurable mechanical leg is selected according to the task requirements. Then, the robot’s gait in walking mode is planned. Firstly, based on bionic principles, the motion characteristics of a mechanical leg based on a mammalian model and an insect model were analyzed. The input and output characteristics of the mechanism were analyzed to obtain the reconfiguration principle of the mechanism. Using type synthesis theory for the decoupled parallel mechanism, the configuration synthesis of the chain was carried out, and the constraint mode of the mechanical leg was determined according to the constraint property of the chain and the motion characteristics of the moving platform. Secondly, an evaluation index for the complexity of the reconfigurable mechanical leg structure was developed, and the synthesized mechanism was further analyzed and evaluated to select the mechanical leg’s configuration. Thirdly, the inverse position equations were established for the mechanical leg in the two motion modes, and its Jacobian matrix was derived. The degrees of freedom of the mechanism are completely decoupled in the two motion modes. Then, the workspace and motion/force transmission performance of the mechanical leg in the two motion modes were analyzed. Based on the weighted standard deviation of the motion/force transmission performance, the global performance fluctuation index of the mechanical leg motion/force transmission is defined, and the structural size parameters of the mechanical leg are optimized with the performance index as the optimization objective function. Finally, with the reconfigurable mechanical leg in the insect mode, the robot’s gait in the walking operation mode is planned according to the static stability criterion. Full article

Bombyx mori, a key lepidopteran model with economic importance, is highly susceptible to environmental heavy metal pollution. This study investigated the mechanisms of Pb toxicity and the associated detoxification and metabolic defense responses in silkworms, employing transcriptome sequencing, enzyme activity assays, and histopathological analysis. Pb exposure caused significant histopathological changes and apoptosis in the fat body, marked by structural disorganization, swollen adipocytes, and degraded extracellular matrix. Molecular analysis showed activation of antioxidant defenses, with superoxide dismutase (SOD) and catalase (CAT) activities significantly elevated (p < 0.05), while peroxidase (POD) activity declined (p < 0.05). Levels of malondialdehyde (MDA) and glutathione (GSH) also decreased. In detoxification responses, carboxylesterase (CarE) activity was reduced, whereas cytochrome P450 (P450) and glutathione S-transferase (GST) activities increased (p < 0.05). Transcriptome sequencing revealed 1,418 differentially expressed genes (DEGs), with notable upregulation of key detoxification genes (p < 0.05), including six cytochrome P450s (CYPs), five uridine diphosphate-glycosyltransferases (UGTs), three glutathione S-transferases (GSTs), and six ATP-binding cassette transporters (ABCs). KEGG enrichment analysis highlighted the involvement of these DEGs in drug metabolism, glutathione metabolism, and ABC transporter pathways (p < 0.05). Functional validation showed that knocking down Cap ‘n’ Collar C (CncC) significantly suppressed key detoxification genes (CYP18A1, CYP332A1, GSTd3, GSTt1, UGT33D8; p < 0.05). qRT-PCR and Western blot analyses confirmed that the Caspase-3 pathway mediates Pb-induced apoptosis, with increased cleaved Caspase-3 and Caspase-4 levels following CncC silencing. Overall, our findings elucidate the mechanisms of Pb toxicity in silkworms and identify CncC as a critical regulator of detoxification and defense against heavy metal stress in lepidopteran insects. Full article

Personal protection from mosquitos is dominated by topically applied aerosol sprays or lotions, which demonstrate efficacy durations of no longer than 10 h, thus encouraging the research and development of long-term insect-repelling devices. Repellent-loaded polymeric matrices have driven the development of insect-repelling apparel fabrics; however, most efforts either fail to offer the tensile properties demanded from apparel applications or only demonstrate repellency durations for multiple days. This study utilizes poly-D,L-lactic acid (PDLLA) as a compatibilizer between Nylon 12 and nootkatone for enhanced nootkatone retention throughout fabric manufacturing processes. Nootkatone-infused Nylon 12/PDLLA composites demonstrate up to a 14% increase in nootkatone retention throughout fabric manufacturing compared to pure Nylon 12, underscoring the importance of polymer/substrate miscibility on substrate retention. Moreover, while nootkatone-infused Nylon 12 filaments demonstrate decreasing tensile stress at breaks with increasing nootkatone content, Nylon 12/PDLLA filaments exhibit similar tensile properties regardless of nootkatone content. The PDLLA domains are suspected to behave as reservoirs for excess nootkatone to prevent its role as a defect within the Nylon 12 matrix. The resulting knits exhibit significant mosquito repellencies over 24 h dependent on the nootkatone concentration, thus demonstrating potential to embed insect repellent within high-performance polymeric filaments with effective mosquito repellencies. Therefore, the incorporation of PDLLA as a compatibilizer holds significant potential for enhanced nootkatone retention during Nylon 12 fabric manufacturing. Full article

As a key pest damaging urban greenery in Yunnan, China, Achelura yunnanensis larvae secrete venom for defense, yet the molecular basis of this process remains poorly understood. This study aimed to uncover the molecular mechanisms of venom secretion by comparing the dorsal epidermis tissue (LDET) with the larval proleg tissue (LP). We performed transcriptomic analysis using RNA sequencing to identify differentially expressed genes between LDET and LP (10 biological replicates per tissue type), followed by functional enrichment and gene expression correlation analyses to explore tissue-specific characteristics. LDET exhibited significant upregulation of pathways related to lipid metabolism, redox reactions, and surface protective structure formation, suggesting their roles in venom stabilization, activation, and safe secretion. Conversely, genes linked to non-venom-related functions, such as extracellular matrix organization and epidermal development, were downregulated in LDET, indicating resource reallocation toward venom production. These findings reveal a multi-component mechanism in LDET that supports venom secretion through metabolic and structural adaptations, with lipid metabolism genes constituting 18.3% of total differentially expressed genes, highlighting evolutionary trade-offs in insect defense. This study provides new insights into insect venom secretion and offers potential targets for pest control strategies. Full article

The increasing popularity of edible insects as a sustainable food source necessitates stringent safety measures to monitor pesticide contamination. This study aimed to assess and enhance a QuEChERS-based extraction method coupled with gas chromatography–tandem mass spectrometry (GC-MS/MS) for the quantification of pesticide residues in edible insects (bamboo caterpillars, house crickets, silkworm pupae, giant water bugs, and grasshoppers) by combining multiple individual insect specimens into a single, homogenized sample—five replicates were tested. The method was optimized by evaluating various extraction parameters and showed strong linearity for all 47 target pesticides, with correlation coefficients (R²) ranging from 0.9940 to 0.9999. The limits of detection (LODs) varied between 1 and 10 µg/kg, while the limits of quantification (LOQs) ranged from 10 to 15 µg/kg. Recovery studies conducted at three fortification levels (10, 100, and 500 µg/kg) revealed recoveries ranging from 64.54% to 122.12%, that over 97.87% of the pesticides exhibited satisfactory recoveries within the range of 70–120%, and relative standard deviations (RSDs) below 20%, between 1.86% and 6.02%. Matrix effects (%MEs) range from −33.01% to 24.04%, and to those that experienced no effect. More than 94% of the analytes showed minimal ion suppression or enhancement. These results conform to the SANTE guidelines for monitoring pesticide residues in edible insects, enhancing food safety standards and safeguarding consumer protection. Full article

In eukaryotes, a lot of proteins are transported across the endoplasmic reticulum by the heterotrimeric Sec61 channel. And post-translational transport needs another Sec62/Sec63 complex. However, functions of these genes are poorly explored in insects. In this study, we first identified five Sec genes, named Sec61α, Sec61β, Sec61γ, Sec62 and Sec63, in Locusta migratoria. Quantitative reverse-transcription polymerase chain reaction (RT-qPCR) analysis showed that these five genes were expressed in muti-tissues, including wing pad, leg, foregut, midgut, gastric cecum, hindgut, and highly expressed in the integument. Knockdown of LmSec61α and LmSec61γ by RNA interference (RNAi) lead to the feeding cessation with a mortality rate of 100%. However, there is only 13.4% of dsLmSec61β-injected nymphs died before molting. All nymphs injected with dsLmSec61α and dsLmSec61γ died before molting with the gut atrophy. Furthermore, hematoxylin–eosin staining indicated that the cells of the midguts and gastric caecum were defective, and the microvilli and peritrophic matrix were destroyed seriously after silencing LmSec61α and LmSec61γ. Knockdown of LmSec62 and LmSec63 resulted in high mortality before and during molting. The hematoxylin–eosin (HE) staining and transmission electron microscopy (TEM) results showed that both the formation of the new cuticle and the degradation of the old cuticle were inhibited in dsLmSec63-injected insects compared to the controls. Especially, there was no obvious plaques on microvillar tips of the epidermal cells after silencing of LmSec63. These results revealed that Sec61s and Sec62/Sec63 genes are required in the gut and cuticle development of locusts. Therefore, these genes are potential targets for the control of locusts. Full article

The use of insect sex pheromones as an alternative technology for pest control in agriculture and forestry offers a promising solution. The development of a novel technology for the biological production of pheromones through yeast fermentation significantly lowers production costs, enabling the adoption of sustainable pest control practices in field crops, a strategy previously reserved for high-value crops. Over three years of monitoring and mating disruption trials in Greek cotton fields, focusing on the cotton bollworm Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), it was confirmed that yeast-derived pheromones exhibit equal efficacy compared to their chemically synthesized counterparts. For the mating disruption of H. armigera, a biodegradable, flowable, and paraffin-based matrix was developed. The matrix adheres to plants, protects the labile pheromone molecules (Z)-11-hexadecenal and (Z)-9-hexadecenal, and controls their gradual release into the environment. These biodegradable polymer blobs act as non-retrievable dispensers and can be deployed manually or via unmanned aerial vehicles (UAVs), ensuring efficient and accurate application. This precise, time-efficient, and economically sound technology aligns with European Commission initiatives, such as the Green Deal’s Farm to Fork Strategy and the Biodiversity Strategy, contributing to food sustainability while respecting biodiversity. Full article

Population growth and the depletion of natural resources have driven the incorporation of edible insects into the human food matrix. Despite their high nutritional value and the environmental benefits of insect farming compared to conventional protein sources, their consumption poses potential risks, including food allergies. Sensitization to insect allergens can occur through various exposure routes, with cross-reactions involving other foods and environmental allergens being well-documented. Vulnerable groups such as children and the elderly may have increased susceptibility not only because of genetic predisposition but also because of age-related physiological factors. This review explores the emerging risks of edible insect consumption, with a focus on children and the elderly. Age-related alterations in the gut microbiota, digestion, immune function, and overall physiology can facilitate the absorption of intact allergenic proteins and impair immune responses. Furthermore, the allergenic potential of insect proteins and their associated microbiota remains poorly characterized. Limited research exists on the effects of processing methods on these proteins. Consequently, incorporating edible insects into food products could present an additional allergenic risk, particularly for these vulnerable populations. Understanding these risks is essential for ensuring the safety and acceptance of edible insects as sustainable food ingredients. Full article