Insects最新文献

{"title":"The Expression Levels of Heat Shock Protein 90 (HSP90) in <i>Galleria mellonella</i> Following Infection with the Entomopathogenic Nematode <i>Steinernema carpocapsae</i> and Its Symbiotic Bacteria <i>Xenorhabdus nematophila</i>.","authors":"Davide Banfi, Maristella Mastore, Tommaso Bianchi, Maurizio Francesco Brivio","doi":"10.3390/insects16020201","DOIUrl":"10.3390/insects16020201","url":null,"abstract":"<p><p>Heat shock proteins (HSPs), particularly HSP90, play a vital role in insect responses to environmental and biotic stresses by maintaining protein stability and supporting immune defenses. This study explores HSP90 regulation in <i>Galleria mellonella</i> larvae following exposure to the nematode <i>Steinernema carpocapsae</i> and its symbiotic bacterium <i>Xenorhabdus nematophila</i>. Exposure to live nematodes caused slight changes in HSP90 expression, while non-viable nematodes had no effect, suggesting that nematode secretions or symbiotic bacteria do not directly influence HSP90 levels. However, nematodes with altered surface properties significantly increased HSP90 expression. <i>X. nematophila</i> also moderately elevated HSP90 levels but this effect disappeared when weakly bound surface proteins were removed. Interestingly, under thermal stress, live nematodes reduced heat-induced HSP90 expression, whereas surface-treated nematodes enhanced it. These findings suggest that HSP90 modulation is influenced by biological control agents, highlighting a potential link between HSP90 and immune detection of invaders. This interaction may be crucial in adapting biological control strategies in response to climate change. Further research is needed to clarify HSP activation pathways, host immune interactions, and mechanisms of entomopathogen immune evasion, particularly under varying environmental temperatures, to enhance bioinsecticide efficacy.</p>","PeriodicalId":13642,"journal":{"name":"Insects","volume":"16 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11856864/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143500962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Laboratory Evaluation of a Novel Insecticide, Isocycloseram, Against the Common Bed Bug (<i>Cimex lectularius</i> L.) (Hemiptera: Cimicidae).","authors":"Xiaodan Pan, Souvic Sarker, Changlu Wang","doi":"10.3390/insects16020200","DOIUrl":"10.3390/insects16020200","url":null,"abstract":"<p><p>Isocycloseram is a novel insecticide belonging to the class of isoxazoline (IRAC MoA Group 30) that exhibits excellent efficacy and selectivity against invertebrate pests. We evaluated the efficacy of two 0.1% isocycloseram formulations against a laboratory and four insecticide-resistant field strains of common bed bugs (<i>Cimex lectularius</i> L.) (Hemiptera: Cimicidae) by direct spray and forced exposure on three surfaces (fabric, vinyl tiles, and unpainted pinewood). Their efficacy was compared with that of five commercial insecticides including Demand CS (0.03% λ-cyhalothrin), Temprid FX (0.05% imidacloprid and 0.025% β-cyfluthrin), Crossfire (0.4% clothianidin, 0.01% metofluthrin, and 1.0% piperonyl butoxide), Bedlam Plus (0.4% d-phenothrin, 1.0% MGK 264, and 0.05% imidacloprid), and PT Phantom II (0.5% chlorfenapyr). Both isocycloseram 45 SC and 400 SC formulations were the most effective among the tested insecticides. The isocycloseram 45 SC formulation caused faster mortality than the 400 SC formulation. Four hours of exposure to 0.025, 0.05, and 0.1% isocycloseram 45 SC residue on porous and non-porous surfaces caused 100% bed bug mortality after 3-4 days. Exposure to 30-day-aged 0.1% isocycloseram 45 SC residue for 4 h still caused 100% mortality, compared to 0-73% mortality by the five commercial insecticides. Isocycloseram is a highly effective compound for controlling resistant <i>C. lectularius</i> populations.</p>","PeriodicalId":13642,"journal":{"name":"Insects","volume":"16 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11856801/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143500817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biodiversity-Friendly Management in Olive Groves Supports Pollinator Conservation in a Mediterranean Terraced Landscape.","authors":"Matteo Dellapiana, Virginia Bagnoni, Laura Buonafede, Alice Caselli, Simone Marini, Malayka Samantha Picchi, Tiziana Sabbatini, Anna-Camilla Moonen","doi":"10.3390/insects16020198","DOIUrl":"10.3390/insects16020198","url":null,"abstract":"<p><p>While olive trees are primarily wind-pollinated, biodiversity-friendly management of the groves can contribute to the conservation of pollinating insects in olive agroecosystems. Previous research demonstrated that semi-natural habitats, such as herbaceous linear elements and woody areas, support the community of pollinators in agroecosystems. Less is known about the contribution of low-input olive groves with a permanent ground cover on terraced landscapes. This study investigated the relationship between pollinator communities and semi-natural habitats, including spontaneous vegetation, in a traditional terraced Mediterranean olive grove agroecosystem. The research employed pan traps to monitor wild bees and observation walks to assess the butterfly community across three different habitat types in spring, summer, and autumn during two growing seasons. Floral resources in the habitats were assessed during each sampling time. Analysis showed that herbaceous habitats support a higher abundance of wild bees than woody areas, while olive groves do not differ significantly from either habitat type, despite exhibiting the highest floral abundance. This suggests that habitat structure, rather than floral availability alone, plays a role in maintaining the wild bee community. For butterflies, results demonstrate that the overall abundance does not differ between habitats, while the species composition does. The study emphasizes the importance of preserving diverse habitats, and in particular low-input olive groves, within agricultural landscapes to support a wide range of pollinator species.</p>","PeriodicalId":13642,"journal":{"name":"Insects","volume":"16 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11856615/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143500705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chemical Profiling, Sensory Qualities, and Bioactivities of Essential Oils Obtained from <i>Aloysia citrodora</i> and <i>Bursera graveolens</i> Ecuadorian Plants Against the Mosquito <i>Aedes albopictus</i> (Skuse) (Diptera: Culicidae).","authors":"Prangthip Parichanon, Roberta Ascrizzi, Camilla Tani, Maria Cristina Echeverria, Sania Ortega Andrade, Hugo Paredes, Isabella Taglieri, Guido Flamini, Francesca Venturi, Barbara Conti","doi":"10.3390/insects16020202","DOIUrl":"10.3390/insects16020202","url":null,"abstract":"<p><p>The mosquito <i>Aedes albopictus</i> is a vector of several harmful viruses, necessitating the development of safer and more sustainable repellents than DEET. This study evaluated the potential of plant-based EOs extracted via steam distillation from <i>Aloysia citrodora</i> and <i>Bursera graveolens</i> plants harvested in Ecuador. <i>A. citrodora</i> EO exhibited a high sensory pleasantness with a citral-like aroma, while <i>B. graveolens</i> EO had lower sensory appeal due to off-flavors. At 200 µL L^-1, <i>B. graveolens</i> EO demonstrated strong ovideterrent activity, reducing egg laying by 64%, whereas <i>A. citrodora</i> EO displayed the highest larvicidal activity with an LC₅₀ value of 88.54 µL L^-1. Both EOs, applied at 0.20 µL cm^-2 on human skin, provided comparable repellency for over 45 min. The RD₅₀ values were 0.104 µL cm^-2 for <i>A. citrodora</i> EO and 0.136 µL cm^-2 for <i>B. graveolens</i> EO. When compared to DEET at 0.04 µL cm^-2, no significant differences in repellency were observed within the first 15 min post-application. These findings suggest that both EOs are effective alternatives to synthetic repellents, and <i>A. citrodora</i> EO emerges as a promising candidate due to its superior sensory attributes and larvicidal activity.</p>","PeriodicalId":13642,"journal":{"name":"Insects","volume":"16 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11857052/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143500713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on the Expression of Immune-Related Genes at Different Stages in the Third-Instar Larvae of <i>Spodoptera frugiperda</i> Infected by <i>Metarhizium rileyi</i>.","authors":"Pengfei Xu, Zhan He, Xuyuan Gao, Xianru Zeng, Dewei Wei, Xiuzhen Long, Yonghao Yu","doi":"10.3390/insects16020199","DOIUrl":"10.3390/insects16020199","url":null,"abstract":"<p><p><i>Spodoptera frugiperda</i> is a major migratory agricultural pest that poses a significant threat to global crop safety. <i>Metarhizium rileyi</i> has emerged as an effective biocontrol agent against lepidopteran pests. In this study, we examined the immune responses of third-instar <i>S. frugiperda</i> larvae at various stages of an <i>M. rileyi</i> infection. Using RNA-seq and microscopic observation, we identified the immune-related pathways enriched at different infection stages, which were further validated by a qRT-PCR. Our findings revealed the following immune responses during infection: During the stage when <i>M. rileyi</i> penetrated the host cuticle (0-48 h), the genes related to energy metabolism, detoxification, and melanization were upregulated. Meanwhile, the TOLL and IMD signaling pathways were activated to counter the infection. During the stage of <i>M. rileyi</i>'s internal infection (48-96 h), which was the peak expression period of the immune-related genes, cellular immunity predominated. Hemocytes encapsulated and phagocytosed the hyphal bodies. Phagocytosis was enhanced through the upregulation of the genes related to ROS and the melanization-related genes, as well as the genes involved in insect hormone biosynthesis. During the stage when <i>M. rileyi</i> grew from the inside to the outside of the host (96-120 h), immune system paralysis resulted in host mortality. These findings deepen our understanding of the immune interactions between <i>M. rileyi</i> and <i>S. frugiperda</i>, support the potential of <i>M. rileyi</i> as an effective biocontrol agent, and provide a theoretical foundation for the development of targeted biopesticides for pests using biotechnological approaches.</p>","PeriodicalId":13642,"journal":{"name":"Insects","volume":"16 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11856804/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143500853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hermetic Bags Effectively Manage Emerging and Common Pests of Stored Cowpeas in Niger.","authors":"Habibou Yahaya Dan Bawa, Ibrahim Boukary Baoua, Mahamane Moctar Rabé, Dieudonne Baributsa","doi":"10.3390/insects16020196","DOIUrl":"10.3390/insects16020196","url":null,"abstract":"<p><p>The cowpea is a vital crop for low-resource farmers in the Sahel, but post-harvest losses due to insect pests remain a major challenge. <i>Callosobruchus maculatus</i> (Fabricius, 1775), is the primary pest responsible for most of the damage to stored cowpeas. Recently, <i>Trogoderma granarium</i> (Everts, 1898) was found infesting cowpeas in large warehouses in Niger. This study evaluated hermetic storage bags to manage both common and emerging insect pests. Treatments included (i) the Purdue Improved Crop Storage (PICS) hermetic bag; (ii) a woven polypropylene (PP) bag with a polyethylene (PE) liner and Phostoxin; and (iii) a woven PP bag without Phostoxin (control). Naturally infested cowpea grains were obtained from the Office des Produits Vivriers du Niger (OPVN) warehouse in Maradi, Niger. Infestation levels were assessed using 12 samples of 500 g each, randomly collected from each treatment at the start and end of the trial. Major pests identified were <i>C. maculatus</i>, <i>T. granarium</i>, and <i>Tribolium</i> sp., with initial populations of 0.83, 0.44, and 0.83 adults per 500 g of cowpea, respectively. After six months of storage, pest densities in the control increased significantly: 232-fold for <i>C. maculatus</i>, 7.4-fold for <i>T. granarium</i>, and 2.7-fold for <i>Tribolium</i> sp.; resulting in a 38.5% weight loss. In contrast, both the Phostoxin and the PICS hermetic bags effectively suppressed pest populations, preventing weight loss. This study confirms the efficacy of hermetic storage, such as the PICS bag, in protecting cowpeas from both common and emerging pests.</p>","PeriodicalId":13642,"journal":{"name":"Insects","volume":"16 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11856402/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143500720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Methodology for the Evaluation of Varietal Resistance to <i>Haplaxius crudus</i>, Vector of the Causal Agent of Lethal Wilt in Oil Palm in Colombia.","authors":"Ivette Johana Beltrán-Aldana, Gladys Alejandra Romero-Guerrero, Eloina Mesa-Fuquen, Anuar Morales-Rodriguez","doi":"10.3390/insects16020197","DOIUrl":"10.3390/insects16020197","url":null,"abstract":"<p><p>Lethal Wilt is a limiting disease for oil palm cultivation in the eastern and central zones of Colombia. In the eastern zone, it caused the eradication of approximately 8700 ha of oil palm between 2010 and 2022, with economic losses of more than 185 million dollars. Studies conducted by Cenipalma reported that the pathogen causing this disease is <i>Candidatus</i> Liberibacter, which is possibly transmitted by <i>Haplaxius crudus</i> (Van Duzee). The adults feed on the foliage of the palms and move between them, spreading the pathogen in the plantation. A strategy to contribute to the management of LW is establishing cultivars resistant to the insect vector; however, no resistant cultivars or sources of resistance have been identified in the country's commercial cultivars or germplasm collections. Therefore, this work aimed to design and validate a methodology to characterize the oil palm genotypes <i>Elaeis guineensis</i> and <i>Elaeis oleifera</i> and interspecific OxG hybrids against adults of <i>H. crudus</i>, evaluating resistance through antixenosis and antibiosis to identify genotypes with possible sources of resistance. An arena with leaflets of the different genotypes in free-choice tests was used to assess antixenosis. For antibiosis, entomological sleeves were installed on the palm leaves, which were infested with adults of <i>H. crudus</i> from a breeding unit. The results of antixenosis and antibiosis in both the first phase (design) and the second phase (validation) indicated greater preference and survival for the genotypes of <i>E. guineensis</i> and lower preference and survival for the interspecific hybrids and <i>E. oleifera</i>. In the genotype <i>E. guineensis</i>, the average mortality was reached after 30 days, while in <i>E. oleifera</i> and the hybrids, it occurred between the third and fourth days. The results of this research provide a reproducible methodology for the evaluation of oil palm germplasms against <i>H. crudus</i> and sucking insects for the selection of sources of resistance for incorporation into breeding programs.</p>","PeriodicalId":13642,"journal":{"name":"Insects","volume":"16 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11856791/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143500827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of Bacterial Communities in Water and Different Developmental Stages of <i>Aedes aegypti</i> from Aquatic Breeding Sites in Leticia City, Colombian Amazon Biome.","authors":"Alejandro Castañeda-Espinosa, Daniela Duque-Granda, Gloria Cadavid-Restrepo, Luz Mila Murcia, Howard Junca, Claudia X Moreno-Herrera, Rafael J Vivero-Gómez","doi":"10.3390/insects16020195","DOIUrl":"10.3390/insects16020195","url":null,"abstract":"<p><p><i>Aedes aegypti</i> is a key vector in the transmission of arboviral diseases in the Colombian Amazon. This study aimed to characterize microbiota composition using DNA extracted from water in artificial breeding sites, immature stages, and adults of <i>Ae. aegypti</i> in Leticia, Amazonas. Additionally, the physicochemical water variables were correlated with the bacterial communities present. Eight artificial breeding sites were identified, with bucket, plant pot, and tire being the most frequent. The breeding sites exhibited similar physicochemical profiles, with significant temperature and salinity differences (<i>p</i>-value < 0.03). The most representative bacterial genera included <i>Ottowia</i> (82%), <i>Xanthobacter</i> (70.59%), and <i>Rhodocyclaceae</i> (92.78%) in breeding site water; <i>Aquabacterium</i> (61.07%), <i>Dechloromonas</i> (82.85%), and <i>Flectobacillus</i> (58.94%) in immature stages; and <i>Elizabethkingia</i> (70.89%) and <i>Cedecea</i> (39.19%) in males and females of <i>Ae. aegypti</i>. Beta diversity analysis revealed distinct clustering between adults and the water and immature communities (<i>p</i>-value < 0.001). Multivariate analysis showed strong correlations among bacterial communities, breeding sites, and physicochemical variables such as tire and drum cover which exhibited high levels of total dissolved solids, conductivity, and salinity associated with <i>Flectobacillus</i>, <i>Leifsonia</i>, <i>Novosphingobium</i>, <i>Ottowia</i>, and <i>Rhodobacter</i>. Bacterial genera such as <i>Mycobacterium</i>, <i>Escherichia</i>, <i>Salmonella</i>, and <i>Clostridium</i>, present in artificial breeding sites, are associated with public health relevance. This study provides insights into bacterial community dynamics across <i>Ae. aegypti</i>'s life cycle and underscores the importance of water physicochemical and biological characteristics for developing new vector control strategies.</p>","PeriodicalId":13642,"journal":{"name":"Insects","volume":"16 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11856942/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143500884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic Diversity and Connectivity of the Vulnerable Species <i>Phengaris nausithous</i> in Palencia (Northern Spain).","authors":"Luis Fernando Sánchez-Sastre, Óscar Ramírez-Del-Palacio, Pablo Martín-Ramos, María-Ángeles Hernández-Minguillón","doi":"10.3390/insects16020193","DOIUrl":"10.3390/insects16020193","url":null,"abstract":"<p><p>Habitat fragmentation is one of the most critical threats to species conservation, particularly for those with strict habitat preferences and specialized feeding and reproductive behaviors. In such cases, dispersal is essential for gene flow, playing a significant role in determining metapopulation dynamics and stability. This is precisely the case for many Lepidoptera, such as the dusky large blue butterfly (<i>Phengaris nausithous</i>), whose larvae feed on a single host plant (<i>Sanguisorba officinalis</i>) before completing their life cycle as social parasites of <i>Myrmica</i> ants. In Spain, <i>P. nausithous</i> is a vulnerable species found only in certain areas along the mountainous fringe of the northern plateau. In one of these regions (northern Palencia province), five populations separated by distances ranging from 2 to 40 km were studied using microsatellite markers, along with a control population located 200 km away (Soria province), to assess their genetic structure and population dynamics. The results revealed a lack of connectivity and pronounced genetic structuring in four of the studied populations. Only two populations within the Montaña Palentina Natural Park exhibited clear connectivity, demonstrating high gene flow between them. This could be explained by the availability and stability of <i>S. officinalis</i> patches, which may function as stepping stones. This study confirms the challenges posed by habitat fragmentation but also demonstrates that <i>Phengaris nausithous</i> can maintain gene flow between relatively distant areas. At a local level, the results provide the first evidence that the populations studied within the western part of the Montaña Palentina Natural Park belong to a single metapopulation, which may encompass the entire natural park.</p>","PeriodicalId":13642,"journal":{"name":"Insects","volume":"16 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11857059/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143500523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"<i>Reticulitermes flavipes</i> (Blattodea: Rhinotermitidae) Response to Wood Mulch and Workers Mediated by Attraction to Carbon Dioxide.","authors":"Tae Young Henry Lee, P Larry Phelan","doi":"10.3390/insects16020194","DOIUrl":"10.3390/insects16020194","url":null,"abstract":"<p><p>The eastern subterranean termite, <i>Reticulitermes flavipes</i>, is challenged by the significant energy expenditures of tunnel construction for resource discovery. Subterranean termites use idiothetic mechanisms to explore large spaces, while the use of resource-specific cues for localized search is disputed. Here, termite response to wood mulch, termite workers, extracts of wood mulch, and CO₂ alone were tested using a bioassay design that distinguished between attraction and arrestment. Termites showed significant attraction to wood mulch with workers or to wood mulch alone. They did not respond to workers alone at the initial dose tested, but were attracted to workers at higher densities. Termites did not respond to water or the acetone extracts of wood mulch, but did show a partial response to hexane extract compared to intact wood mulch. More significantly, when CO₂ was removed from the emissions of wood mulch and workers using soda lime, attraction was eliminated. Furthermore, termites showed a quadratic response to CO₂ concentration that peaked at ca. 14,000 ppm. The response to CO₂ alone predicted by the model matched termite response to mulch + workers when compared at the level of CO₂ they emitted. The results suggest that CO₂ is both necessary and sufficient to explain the attraction response of <i>R. flavipes</i> to mulch and workers we observed. It is argued that orientation to food cues complements the previously demonstrated idiothetic program to maximize the efficiency of resource location.</p>","PeriodicalId":13642,"journal":{"name":"Insects","volume":"16 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11856009/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143500350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}