Frontiers in insect science最新文献

Faba bean (Vicia faba L.) is one of the most important cool-season legume crops worldwide, particularly in the Mediterranean regions. It plays a crucial role in cereal-based crop rotations and serves as an accessible and cost-effective protein source for both human diets and livestock feed. Despite its significance, faba bean production is heavily impacted by the stem borer Lixus algirus L. (Coleoptera: Curculionoidea), a prominent insect pest in the Mediterranean region. This research aimed to assess the impact of L. algirus on grain yield and seed nutritional profile of a local variety 'Defes'. The experiment was conducted using insect-proof cages at ICARDA - Marchouch research station during the 2018-2019 and 2019-2020 seasons. The findings revealed that L. algirus infestation caused grain yield losses ranging from 14% to 20%. Larval feeding within plant stems significantly altered seed nutritional composition compared to seeds from non-infested plant, ICP-OES analysis revealed significant declines were observed in magnesium (44%), manganese (38%), calcium (37%), zinc (30%), and iron (27%) concentrations in seeds collected from infested plants. In contrast, an increase in seed protein content and total sugar levels was recorded in infested plant seeds compared to non-infested plants. Similar results were observed for both essential amino acids (such as threonine, isoleucine, leucine, phenylalanine, histidine, lysine, and arginine) and non-essential amino acids (including glutamic acid, tyrosine, and alanine). Multivariate analyses, including PCA and correlation, revealed distinct nutrient and morphological trait patterns between infested and non-infested faba bean samples across both seasons. Collectively, these results show that L. algirus not only reduces grain yield but also reconfigures seed nutritional quality, lowering mineral density despite higher protein and sugars, highlighting the need for integrating host plant resistance for stem borer management and timely IPM to preserve both productivity and food/feed quality.

Diaprepes abbreviatus is an agricultural pest known to affect around 270 plant species across the Caribbean and the United States, posing significant challenges to pest management. Chemical control dominates management, but environmental and health concerns motivate microbiome-informed alternatives. However, limited information exists on the gut anatomy, physicochemical environment, and microbial composition of D. abbreviatus. In this study, we provide the first comprehensive characterization of the gut morphology, pH, and microbiota of adult D. abbreviatus in both females and males collected in Puerto Rico. Using dye-based gut tracing, we identified foregut, midgut, and hindgut or posterior gut compartments, and confirmed the presence of a muscular, sclerotized gizzard. Colorimetric analysis revealed a mildly acidic gut environment (approximately pH 4-5, based on qualitative ranges), consistent across sexes and regions. Shotgun metagenomic sequencing of dissected guts from males and females revealed microbial communities distinct from the leaf samples microbiota. While alpha and beta diversity did not differ significantly between sexes, co-occurrence analyses identified sex-specific correlation patterns among bacterial taxa. Notably, Enterobacter cloacae, Pantoea vagans, Lactococcus lactis, and Pseudomonas monteilii were repeatedly detected across individuals and generated metagenomic datasets, and some were localized to the hindgut, suggesting possible niche specialization. The presence of taxa, such as Enterobacter cloacae, previously reported as symbionts in other phytophagous insects further supports the hypothesis that certain bacteria may contribute to host digestion or adaptation. These findings establish a framework for understanding the gut environment and microbial community of D. abbreviatus, and highlight candidate taxa for future functional studies. More broadly, this work supports further research into the potential roles of gut microbiota in the ecology and management of this pest.

Termites are eusocial and economically important insects which are found in the world's tropical regions as a harmful or beneficial organism. They play a dual role, both as pests damaging crops and urban structure and as an ecological engineer sustaining the ecosystem. Pakistan is part of the Indomalayan realm hosting diverse flora and fauna including termites; however, the status (diversity, distribution, feeding hosts, pest and non-pest) of the genus Angulitermes in the northwestern region (Khyber Pakhtunkhwa, Pakistan) has been largely neglected. Termite cultures were collected from diverse ecosystems, cleaned, and preserved in alcohol-filled vials for subsequent morphometric identification and DNA barcoding. Coordinates with relevant ecological data were also recorded. Soldiers were used for capturing refined images and morphometric identification through available literature, which resulted as an Angulitermes dehraensis and a new locality record. A revised and updated world's species list for the genus was made along with the distribution map of this study via ArcGIS. The identified representative soldier's leg was processed for mtDNA extraction followed by amplification and sequencing. The received sequence was subjected to BLASTn search, and only top 15 sequences via BLASTn search and then via manual search for taxon Angulitermes were retrieved from GenBank. Aligned and trimmed sequences were processed for phylogenetic tree (neighbor-joining and maximum-likelihood) construction and validation of understudy species sequence analogy. A novel sequence was submitted to GenBank for accession number (PX423737). Based on the available and recorded feeding host substrate data, it is a pest species which needs management.

While biopesticides have been around for 70 years, starting with Bacillus thuringiensis bioinsecticides, they are experiencing rapid growth as the products have gotten better and more science-based and there are more restrictions on synthetic chemical pesticides. The growth of biopesticides is projected to continue to outpace that of chemical pesticides, with compounded annual growth rates of 10%-20% versus single digits for chemicals. When integrated into pest management programs, biopesticides offer the potential for higher crop yields and quality than chemical-only programs. Added benefits include the reduction or elimination of chemical residues, therefore easing export, delay in the development of resistance by pests and pathogens to chemicals, shorter field re-entry, biodegradability and lower carbon footprint and greenhouse gas emissions, and low risk to non-target organisms, including pollinators. However, many challenges still exist to drive further the adoption of biopesticides. These include lack of awareness and education in how to test and deploy their unique modes of action in integrated programs, resulting in lingering perceptions about performance and cost-effectiveness. This article addresses these issues with suggestions on how to increase farmer and key influencer confidence in the deployment of biologicals in integrated pest management (IPM) programs, including adjusting IPM thresholds and practice based on the modes of action of biopesticides compared to synthetic chemicals.

Honey bees are essential pollinators in global food production, however, their populations are increasingly threatened by insecticides. Protecting bees from these chemical stressors is critical not only for ecosystem stability but also for agricultural sustainability. Natural dietary compounds, such as curcumin (CU) and rosmarinic acid (RA), have demonstrated antioxidant and detoxification-promoting properties in other organisms and may offer a promising approach to enhancing honey bee resilience to pesticide exposure. This study investigates the potential of CU and RA to mitigate pesticide-induced harm in honey bees. In acute toxicity tests, newly emerged bees and foragers were topically exposed to lethal doses of acetamiprid (1.04 µg/bee for newly emerged and 15.3 µg/bee for forager), carbaryl (0.06 µg/bee for newly emerged and 0.51 µg/bee for forager), and flupyradifurone (15.6 µg/bee for newly emerged and 24.1 µg/bee for forager), followed by post-feeding with CU and RA at 50, 100, and 200 ppm for 48h. Additionally, the effects of CU and RA at 100 ppm were tested under chronic oral intoxication through continuous insecticide feeding. CU100 significantly reduced mortality in insecticide-exposed bees, except foragers exposed to acetamiprid, while RA showed variable detoxification effects, with RA100 and RA200 improving survival in carbaryl-exposed bees and RA50 enhancing survival of 0.06 µg/bee for newly emerged bees exposed to flupyradifurone. Chronic toxicity assessments confirmed CU100's superior protective effect over RA100, especially in carbaryl-exposed groups. Gene expression analysis revealed that CU and RA modulated detoxification related genes, enhancing honey bees' resilience by upregulating key detoxification genes in the head and abdomen. These findings suggest that CU and RA offer potential benefits in reducing insecticide toxicity in honey bees. However, further research is needed to assess their effects across different life stages, environmental conditions, and colony dynamics, as well as to elucidate the pathways involved in detoxification gene regulation. A comprehensive understanding of their mechanisms and ecological implications is essential before considering these compounds for practical applications in pollinator health management.

Monochamus saltuarius is an important wood-boring pest of forests and a vector insect for the transmission of Bursaphelenchus xylophilus in China and other East Asian regions. To gain insight into the Mo. saltuarius olfactory system, we characterized the sizes and morphological characteristics of sensilla on antennae, maxillary palps, and labial palps of adults by scanning electron microscopy. Eight types of antennal sensilla were identified on the antennae: Böhm bristles (BBs), sensilla chaetica (SChs, with subtypes SChI and SChII), sensilla trichodea (STs, with subtypes STI, STII and STIII), sensilla auricillica (SAus), sensilla basiconica (SBs, with subtypes SBI and SBII), sensilla grooved peg (SGPs), dome shaped organs (DSOs), and cuticular pores (CPs); among these, BBs, STIs, STIIs, SChIs, and SChIIs may be mechanoreceptors, and STIIIs, SAus, SBIs, SBIIs, SGPs and CPs may be chemoreceptors. Seven sensillum types were identified on maxillary palps and labial palps: BBs, STs (with subtypes STII, and STIII), SChs, sensilla placodea (SPs), sensilla coeloconica (SCos), CPs, and sensilla twig basiconica (STBs, with subtypes STBI, STBII, STBIII, and STBIV), among which BBs, STIIs, and SChs may be mechanoreceptors, and STIIIs, SPs, CPs, STBIs, STBIIs, STBIIIs, and STIVs may be chemoreceptors. DSOs on the antennae and SCos on the palps may be hydroreceptors, and/or thermoreceptors. The types and densities of sensilla increased from the base to the tip of the antennae, and sensilla with chemical-sensing functions were concentrated mostly on the flagellum. Identification of these sensillum types provides a basis for analyzing the mechanisms of host recognition and environmental perception of Mo. saltuarius.

Introduction: The genus Bifidobacterium is a key component of the honey bee gut microbiota, playing a fundamental role in maintaining host health and colony well-being. Alongside other core genera such as Bombilactobacillus, Gilliamella, Lactobacillus, and Snodgrassella, Bifidobacterium contributes to essential functions including nutrient digestion, immune modulation, and protection against pathogens. Among threats to honey bee health, Chalkbrood disease, caused by fungus Ascosphaera apis, remains a major concern due to detrimental effects on colony strength and honey yield.

Materials and methods: We characterized enzymatic activity and carbohydrate assimilation of nine Bifidobacterium strains isolated from the honey bee intestinal tract. In parallel, we assessed antifungal potential against A. apis strains, focusing on volatile organic compounds (VOCs).

Results and discussion: Notably, Bifidobacterium asteroides 3CP-2B exhibited enzymatic capabilities supporting digestive functions and metabolism of sugars potentially harmful to honey bees. This strain showed marked antifungal activity against A. apis, mediated by volatile and non-volatile bioactive metabolites. Among VOCs identified, propanoic acid, ethanol, acetic acid, ethyl propionate, and 1-propanol were the most prominent compounds associated with the antifungal effect.

Spodoptera frugiperda (J.E. Smith), (Noctuidae, Lepidoptera), commonly known as fall armyworm (FAW), is a significant polyphagous pest that can cause considerable damage to various crops. Fundamental research on FAW is crucial and beneficial for creating an integrated management strategy. Lot of literatures are available on web to describe the fitness of FAW via conventional methods that deals the basic biology of FAW. However, there is currently a need to check the fitness for each stage of FAW using an advanced two-sex life table tool, which is crucial for creating efficient control strategies. The proposed study used an age-stage, two-sex life table to examine the lifetable parameters of FAW on four natural hosts: castor beans (Ricinus communis), potatoes (Solanum tuberosum), maize (Zea mays L.), and wheat (Triticum aestivium L.). The findings demonstrated that, despite notable variations in development and reproduction, the FAW completed its life cycle on each of the four studied hosts. The FAW that were fed maize performed at their best, showing shorter immature (egg-pupa) phases, longer lifespans, and better rates of adult reproduction. On maize, female FAW had the highest fecundity (2497.1 eggs/female), while on wheat, it was the lowest (675 eggs/female). With values of 532.8 (offspring individual-1), 0.21d^-1, and 1.23 d^-1, respectively, net reproductive rate, intrinsic rate of increase, and finite rate of increase peaked on maize, while the corresponding parameters were lowest on wheat (94.62 offspring individual^-1, 0.11 d^-1, and 1.12 d^-1, respectively). This study indicates that all host plants can contribute to the development and outbreak of this pest in the absence of its primary host. Therefore, all potential host plants in the area should be thoroughly examined when developing an IPM program against said pest.

The intracellular bacterium Wolbachia pipientis has emerged as a promising tool for controlling mosquito-borne diseases; however, key aspects of its biology remain insufficiently understood, particularly how Wolbachia influences vector competence for certain arboviruses. The main factors implicated are the activation of mosquito antiviral pathways and competition for cellular resources at the viral replication site. Transinfection of Wolbachia strains into vector populations has proven to be an effective strategy for controlling arboviral diseases. Here, we investigate the within-host density and tissue distribution of two naturally occurring Wolbachia strains-wAlbA and wAlbB-n Aedes albopictus from Argentina, where infection patterns diverge from those observed globally. Using quantitative PCR, we assessed symbiont density in ovarian (n = 5) and somatic tissues (n = 5) of adult females, and in adult males across different ages: 0, 5 and 14 days post-emergence (n = 5 per age group). Our results reveal superinfection in ovaries (wAlbA + wAlbB) with similar densities (median relative density _{w AlbA} = 3.78 and median relative density _{w AlbB} = 3.31), but only wAlbB was consistently detected in somatic tissues (median relative density _{w AlbB} = 0.41), suggesting tissue-specific distribution of strains. Additionally, wAlbB density in males remained stable throughout the adult lifespan (median relative density_Time0 = 0.83; median relative density_{time 5} = 1.98; median relative density_{time 14} = 0.66). These findings support the hypothesis that Wolbachia somatic localization is strain-specific and may be under evolutionary selection, with implications for vertical transmission and host fitness. By advancing our understanding of Wolbachia density dynamics in a natural mosquito vector population, this study contributes critical baseline data to inform and optimize Wolbachia-based biocontrol strategies in regions at risk of arboviral outbreaks. Because the wAlbB strain from Ae. albopictus is widely used in replacement techniques, any knowledge of its behavior in natural host populations is valuable.

The broad range of Scolytinae pests sizes and their subtle visual similarities, especially in smaller species, continue to challenge the accuracy of mainstream object detection models. To address these challenges, this paper proposes GIWT-YOLO, a lightweight detection model based on YOLOv11s, specifically tailored for Scolytinae pests detection. (1) We designed a lightweight multi-scale convolution module, GIConv, to improve the model's ability to extract features at different pest scales. This module enhances the accuracy of small-object detection while reducing the computational cost and parameter complexity of the backbone. (2) The WTConv module inspired by wavelet transform is introduced into the backbone. This enlarges the effective receptive field and improves the model's ability to distinguish pests with similar textures. (3) An SE attention mechanism is incorporated between the Neck and Head to enhance the model's focus on key feature regions. Experimental results show that GIWT-YOLO achieves 84.7% in Precision, 88.7% in mAP@50, and 63.4% in mAP@50~95, which are improvements of 2.2%, 4.0%, and 3.1%, respectively, compared to the baseline YOLOv11s. Additionally, the model's parameters and GFLOPs are reduced by 11.3% and 13.4%, respectively. Our proposed model surpasses the state-of-the-art (SOTA) performance in small-sized pest detection while maintaining a lightweight architecture, and its generalization ability has been validated on other public datasets. Our model provides an efficient solution for detecting Scolytinae pests. In future work, we plan to collect additional images of various pest species to expand the dataset, further enhancing the model's applicability to a wider range of pest detection scenarios.