Entomological Research最新文献

Understanding the molecular aspects of the susceptibility status of mosquitoes to insecticides could help tackle the problem of insecticide resistance. One of the most important molecular profiles is the amino acids involved in the synthesis of metabolic resistance proteins. In this study, the amino acid profile is compared for three different deltamethrin resistance statuses of Aedes albopictus (Skuse), namely, the VCRU strain (susceptible in the laboratory), the Balik Pulau strain (susceptible in the field), and the Glugor strain (resistant in the field). The resistance status to the insecticide was determined using the WHO adulticide tube test. The mosquito samples were later freeze-dried and derivatized by silylation and then analyzed by gas chromatography–mass spectrometry (GC–MS). Using standardized, known concentrations of amino acids, we quantified the amino acids in three different strains. A one-way ANOVA was performed to compare the concentrations of amino acids between the strains. Of the 12 amino acids obtained from the extraction, our results showed that the susceptible strains from the laboratory and the field were not significantly different, suggesting that the profile may represent the status of susceptibility. More importantly, the resistant strain in the field had a significantly higher concentration of alanine, valine, and glycine and a significantly lower concentration of the other eight amino acids. This suggests possible metabolic adaptations related to insecticide resistance, possibly involving detoxification processes or changes in protein synthesis.

The complete mitochondrial genome (mitogenome) of Tropilaelaps mercedesae (Acari: Laelapidae), which is a serious ectoparasite of several honeybee species, was sequenced and characterized for its genomic features. The results were then compared with those of other available Dermanyssoidea members and used to reconstruct phylogenetic relationships within Dermanyssoidea. Moreover, the current T. mercedesae mitogenome from South Korea was compared with publicly available data from China to determine suitable genes for a subsequent population-level study. Peculiarly, the 15,119-bp long T. mercedesae mitogenome has an 899-bp-long control region containing four copies of a repeat unit that are interrupted by non-repeat sequences. Additionally, T. mercedesae has a new gene arrangement among the Dermanyssoidea species, revealing eight translocated genes, one inverted tRNA block, and one inverted and translocated tRNA. Phylogenetic analyses, which included all available public data, clearly indicated non-monophyletic Laelapidae to which the current T. mercedesae is included. Comparison of two geographic samples of T. mercedesae evidenced several protein-coding genes, including nad5 and cytB (the two most variable), which had higher variability than that of cox1, thus suggesting the potential usefulness of these gene sequences for population genetic studies. Current T. mercedesae mitogenome sequences could provide baseline information for subsequent population-level studies and phylogenetic inferences at diverse taxonomic levels within Dermanyssoidea.

In this study, sequences of the mitochondrial NADH dehydrogenase 4 (ND4) gene for 137 native Apis mellifera jemenitica colonies from Saudi Arabia were analyzed. Results revealed eight new ND4 nucleotide haplotypes (1311 bp) and four amino acid haplotypes. Most mtND4 gene sequences (> 92%) of A. m. jemenitica were identical. However, four samples (3%) showed unusually highly polymorphic sequences. Within-population evolutionary diversity mean in ND4 nucleotide sequences was very low (0.0004). ND4 sequence variations among A. m. jemenitica and the most closely related subspecies A. m. syriaca and A. m. lamarckii were minimal by an average genetic distance of less than 0.005. The lowest evolutionary divergence mean was reported between A. m. jemenitica and A. m. syriaca. Results also showed that most A. mellifera subspecies included in this study could be separated from most A. m. jemenitica samples using one or more variations in amino acid sequences. Distinct amino acid sequence variations, particularly at codon 316, and differences in the restriction map of SspI can separate most A. m. jemenitica samples from the closely related subspecies, A. m. lamarckii and A. m. syriaca. Phylogenetic analyses showed that 19% of the DN4 nucleotide sequences of all samples and 100% of the amino acid sequences from Tabuk and Madinah clustered with the A. m. syriaca reference sequence, indicating a closer evolutionary relationship with the neighboring subspecies, A. m. syriaca. Results also demonstrated the likelihood of a small population with high genetic variability. This might indicate the presence of intensively hybridized colonies within the entire A. m. jemenitica population native to Saudi Arabia. Results also revealed that mtND4 sequence analyses could be used successfully to distinguish A. m. jemenitica of Saudi Arabia from other A. mellifera subspecies belonging to different evolutionary lineages such as A. m. mellifera, A. m. carnica, A. m. simensis, and A. m. intermissa. The close evolutionary relationship between A. m. jemenitica and A. m. syriaca or A. m. lamarckii and the approaches to separate them should be considered in any conservation efforts of A. m. jemenitica in Saudi Arabia.

This study investigates the effects of corn and an artificial diet on life history, and nutritional physiology of Conogethes punctiferalis larvae. Nutritional indices such as food consumption index (CI) and relative growth rate (RGR) were evaluated for the fourth and fifth instars on both diets. The results indicated no significant difference in CI between the diets. However, RGR was significantly higher for larvae reared on corn (p < 0.05). Fifth-instar larvae on corn exhibited the highest RGR (1.08 ± 0.01), while the lowest RGR was observed for 1-day-old fourth instars on artificial diet (0.02 ± 3.21). The efficiency of conversion of ingested food (ECI) and digested food (ECD) were also significantly higher for larvae on corn (p < 0.05), suggesting superior nutrient assimilation and conversion efficiency compared to artificial diet. Despite similar developmental durations, larvae on artificial diet had a higher survival rate (87.32%) than those on corn (75.01%). Pupal weight was slightly higher on artificial diet, but fecundity was greater on artificial diet (133.63 eggs with 90.76% fertility) compared to corn (129.67 eggs with 86.60% fertility). These findings indicate that corn while promoting higher growth rates and nutrient utilization efficiency, may include less digestible components, whereas artificial diet offers better overall survival and reproductive outcomes. This highlights the potential of optimizing artificial diets to enhance the laboratory rearing efficiency of C. punctiferalis for research and pest management applications.

C-type lectins (CTLs) are essential pattern-recognition receptors involved in insect innate immunity, mediating defense responses through carbohydrate binding. In this study, we aimed to clone and functionally characterize Bombyx mori CTL4 (BmCTL4), focusing on its immunity-related functions and binding specificity. To this end, the BmCTL4 cDNA was cloned and the recombinant BmCTL4 protein was expressed using a baculovirus expression system. The recombinant protein was then used to assess its binding specificity via carbohydrate-binding and microbial cell-binding assays. BmCTL4 contained a single carbohydrate recognition domain (CRD) with a QPD motif, suggesting specificity for galactose-type sugars. BmCTL4 was upregulated in the fat body following microbial inoculation. Recombinant BmCTL4 exhibited Ca²⁺-dependent binding to microbial cell wall constituents such as LPS, mannan, N-acetyl-D-glucosamine, and peptidoglycan, and directly bound to microbial cell surfaces as confirmed by confocal microscopy. Our findings demonstrate that BmCTL4 acts as a pattern-recognition receptor with broad carbohydrate-binding activity, contributing to the immune defense mechanisms of B. mori.

Pest development of resistance to Bacillus thuringiensis (Bt) insecticidal proteins threatens the sustainability of Bt crops, and it is therefore necessary to explore ecofriendly alternative insecticides for controlling Bt-resistant populations. Isothiocyanates are plant secondary metabolites that exhibit a diverse array of types and resistance against a broad spectrum of insect pests, but their effects on pink bollworms remain unexplored. Here, we evaluated the effects of phenyl isothiocyanate on Bt-susceptible and Bt-resistant pink bollworms (Pectinophora gossypiella). The LC₅₀ values of phenyl isothiocyanate for Bt-susceptible and Bt-resistant larvae were 26.4 and 28.6 μg/mL, respectively. The LC₃₀ sublethal dose of phenyl isothiocyanate significantly impaired the 7-day larval survival, the pupation rate, neonate-to-adult survival, the pupal weight, eggs per female and the egg hatching rate and prolonged the larval developmental period but not pupal duration for both strains. The response to phenyl isothiocyanate ingestion did not differ significantly between the two strains, implying that the Bt-resistant strain did not possess cross-resistance to phenyl isothiocyanate. These results provide scientific evidence for enriching green control technologies, resistance management tactics and comprehensive management measures for pink bollworm.

Pollination, a keystone ecological process sustaining most flowering plant communities, is indispensable to human survival, with over 500 cultivated plant species relying on insect pollinators. Solitary bees (Hymenoptera: Apoidea) are critical contributors to this service, requiring specialized foraging, nesting, and habitat resources. Plant diversity strongly correlates with pollinator community composition, underscoring the ecological interdependence of these groups. Within solitary bees, the family Halictidae (~4500 species) plays a disproportionately significant role in global pollination networks. Halictids exhibit remarkable diversity in social organization—ranging from solitary to communal, semi-social, and primitively eusocial behaviors—shaped by floral resource availability, geographic distribution, and climatic factors. The subfamily Halictinae represents the group's greatest diversity, with the tribe Halictini comprising 53.3% of described species. Key pollinator genera such as Lasioglossum (e.g., Lasioglossum marginatum, Lasioglossum leucozonium) dominate temperate ecosystems. However, population declines in solitary bees have severely disrupted pollination services across wild and cultivated plant systems, exacerbating global concerns over insect biodiversity loss and biomass reduction. These declines threaten foundational ecosystem services, necessitating urgent research to refine species diversity estimates, identify habitat conservation priorities, and implement evidence-based protective policies. This review highlights the need for standardized methodologies to accurately assess global bee diversity and proposes targeted strategies to mitigate conservation challenges for Halictidae and other solitary bee taxa.

This study was conducted to investigate the effect of high temperature (45°C–80°C) on two major stored product insects and the effect on germination of cowpea seeds. High temperature influenced mortality% of adults, immature stages, hatchability%, reduction% of insects and weight loss% as well as germination% of seeds. The complete mortality 100% of Callosobruchus maculatus was obtained with the treatment 55°C/40 min, 60°C/30 min, 65°C/20 min, 70°C/20 min, 75°C/15 min, and 80°C/5 min. The complete mortality 100% of Rhyzopertha dominica was obtained with the treatment 55°C/30 min, 60°C/25 min, 65°C/20 min, 70°C/15 min, 75°C/10 min, and 80°C/5 min. Furthermore, the temperature at 45°C/30 min, 55°C/20 min, 60°C and 65°C/15 min, 70°C and 75°C/10 min, and 80°C/5 min did not have any harmful effects on humans or on the environment. The best results were achieved with application of temperature at 45°C/30 min, 55°C/20 min, 60°C and 65°C/15 min, 70°C and 75°C/10 min, and 80°C/5 min without injurious effects on grain and seed germination.