Search Results (5,528)

Ethanol is a pervasive chemical stressor in fermentative environments and represents a major ecological challenge for Drosophila melanogaster, a species that naturally inhabits decaying fruits. Although ethanol tolerance has traditionally been attributed to detoxification and antioxidant pathways, accumulating evidence indicates that immune-related genes, particularly those encoding immune deficiency (IMD) pathway-associated antimicrobial peptides (IMD-AMPs), contribute importantly to chemical stress adaptation. Previous studies have demonstrated that IMD-AMP induction is required for ethanol tolerance; however, whether elevated IMD-AMP expression alone is sufficient to enhance tolerance has remained unresolved. In this study, we investigated the functional significance of IMD-AMP upregulation in ethanol tolerance using dietary propolis as an experimental immune-modulating agent. D. melanogaster were reared throughout their life cycle on propolis-supplemented diets and subsequently exposed to ethanol. Propolis-fed flies exhibited significantly enhanced survival under ethanol stress compared with control flies. Notably, this increased tolerance was not accompanied by upregulation of classical ethanol metabolism genes or broad induction of antioxidant-related genes. Instead, propolis feeding increased baseline and early-stage expression of IMD-AMP genes, including Diptericin A (DptA), Diptericin B (DptB), Attacin (AttC), and Metchnikowin (Mtk) before and during ethanol exposure. These findings suggest IMD-AMP upregulation is positively associated with enhanced ethanol tolerance in D. melanogaster. Our results establish a proactive role for immune-related pathways in chemical stress resistance and extend the functional scope of AMPs beyond pathogen defense. This study identifies IMD-AMPs as key effectors linking immune activation to physiological adaptation under ethanol-induced chemical stress. Full article

Immature ladybeetles and lacewings can thrive by feeding on eggs of lepidopteran pests, such as Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae). However, considering that the survival and fitness performances of generalist predators are heavily dependent on their ability to select suitable prey, we first evaluated whether eggs of S. frugiperda strains with differential susceptibilities to Bacillus thurigiensis (Bt) toxins would affect the food preference of larvae of the ladybeetle Coleomegilla maculata DeGeer (Coleptera: Coccinellidae) and the lacewing Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae). We further determined, for the first time, the functional responses of all immature phases of both predator species when fed with S. frugiperda eggs. In our choice bioassays, predator larvae were individually offered 25 eggs of each S. frugiperda strain. The number of consumed eggs was recorded hourly and replenished during each evaluation. For the functional responses, increasing densities of S. frugiperda eggs were offered to the larvae of lacewings and ladybeetles, and the number of consumed eggs was recorded 24 h after the release of the predator. Ch. externa larvae had a generalized preference for Bt-susceptible strains of eggs, while Co. maculata exhibited such a ,preference only during the first evaluation hour. Both predators displayed type II functional responses, and their consumption substantially increased during larval development. By demonstrating that lacewing and ladybeetle larvae can satisfactorily consume S. frugiperda eggs, including eggs from Bt-resistant individuals, our findings reinforce the potential of these predatory insects for the ecological management of S. frugiperda. Full article

Storage insects consist a continuous global threat to food safety. In this study, the efficacy of the entomopathogenic nematodes (EPNs) Steinernema khuongi and Heterorhabditis downesi was evaluated against larvae of Tribolium castaneum, Tribolium confusum, Tenebrio molitor, and Trogoderma granarium in wheat and maize at six concentrations and two exposure intervals. Both EPNs exhibited higher virulence when applied in wheat than in maize. Generally, larval mortalities were higher under H. downesi treatments vs. S. khuongi, both in commodities and exposures. Notably, the tested EPNs caused high mortalities to T. granarium larvae (range, 88.9–92.2%) and T. castaneum larvae (range, 81.1–94.4%), respectively, at 10,000 IJs/mL in wheat vs. mortality ranges 72.2–77.8% and 74.4–87.8% in maize, respectively. In contrast, T. confusum larvae were tolerant to both EPNs. Tenebrio molitor larvae were tolerant to S. khuongi (<34.0% mortality) whereas susceptible to H. downesi (>83.3% mortality) at 10,000 IJs/mL in wheat and maize. These findings highlight the potential of S. khuongi and H. downesi as beneficial organisms against several stored-product insect pests. Full article

The black soldier fly, Hermetia illucens (Linnaeus, 1758), is a globally farmed insect reared to convert organic waste into useful biomatter and materials. While research on optimizing bioconversion rates and larval development through substrate manipulation has surged, studies on larval behavioral responses to abiotic factors lag. This benchtop-scale study is the first to examine larval behavior in response to reduced airflow. The results suggest third to fifth instar H. illucens larvae, which typically burrow within the substrate and avoid the surface, are significantly more likely to aggregate at the surface of their substrate when in a restricted airflow environment. More than half of third instar and nearly all 5th instar larvae aggregated at the surface when airflow was restricted, compared to less than a quarter under ventilated conditions. This data should stimulate future directions of hypothesis building in larval behavioral and physiological responses to airflow with the goal of using behavior modification to facilitate larval production. Full article

Background: The litchi fruit borer, Conopomorpha sinensis (Lepidoptera: Gracillariidae), is a devastating pest affecting litchi and longan production across Asia. Although a reference mitochondrial genome (mitogenome) has been published, its utility is limited by the lack of precise geographical data and raw sequencing data. Methods: In this study, we sequenced and characterized the complete mitogenome of C. sinensis collected from Taiwan using a hybrid assembly of Illumina and Oxford Nanopore technologies. Results: The assembled mitogenome is 17,301 bp in length with a mean sequencing depth of 19,155-fold, comprising 13 protein-coding genes (PCGs), 22 transfer RNA genes, two ribosomal RNA genes, and an AT-rich control region. Notably, we identified a rare tRNA gene rearrangement (trnR-trnA-trnN-trnS1-trnE-trnF) that deviates from the ancestral lepidopteran ditrysian pattern. Comparative analysis revealed a 94.65% overall sequence identity with the reference mitogenome, though the PCGs remained highly conserved at 99.35%. Variant analysis demonstrated that this divergence is predominantly driven by structural variations (228 indels) rather than nucleotide substitutions (2 SNPs) across the entire mitogenome; furthermore, 94.7% of the indels were identified in the control region and intergenic spacers. Subtle differences in codon usage were also observed in the ND6 start codon (ATT vs. ATA) and COX1 stop codon (TAA vs. T). Phylogenetic and molecular clock analyses robustly clustered the Taiwan specimen within the C. sinensis clade. Molecular dating estimates that the Conopomorpha lineage originated during the Late Cretaceous (~77.23 Ma). Notably, the divergence between the Taiwan specimen and the reference lineage was estimated to be negligible (<0.01 Ma) within the protein-coding regions, demonstrating a high degree of purifying selection that maintains coding-sequence stability across geographically distinct specimens, even as substantial variation accumulates in non-coding genomic regions. Conclusions: These findings provide high-resolution genomic resources and a temporal framework for the evolutionary study of Gracillariidae, offering foundational tools for targeted pest management. Full article

The peach fruit fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae), is a climate-sensitive agricultural invader that threatens fruit production across the Arabian Peninsula, yet its realized climatic niche and future exposure under warming remain insufficiently resolved. We used Maximum Entropy (MaxEnt) modeling to quantify current and projected habitat suitability across the region (~3.2 million km²) under two Shared Socioeconomic Pathway scenarios (SSP1-2.6 and SSP5-8.5) for the 2050s and 2070s, based on 55 spatially filtered occurrence records and seven non-collinear environmental predictors, with sampling bias controlled using a Gaussian kernel density bias file. Model performance was robust, with mean training AUC of 0.922 ± 0.011 (SD) and mean TSS of 0.538 ± 0.115 (SD; range: 0.368–0.692), indicating moderate variability across replicates. Suitability was governed primarily by elevation, mean temperature of the driest quarter (Bio 9), mean diurnal temperature range (Bio 2), and precipitation of the coldest quarter (Bio 19), which together contributed over 97% of the model output, indicating strong climatic and topographic control on range persistence. Under present conditions, 790,714 km², or 28.38% of the study area, was suitable, concentrated in the southwestern highlands of Saudi Arabia and Yemen, the Omani mountain ranges, and coastal fringes of the Arabian Gulf and Gulf of Oman. Future projections showed a consistent net contraction of suitable habitat across all scenarios, from 7.4% under SSP1-2.6 in the 2050s to 28.0% under SSP5-8.5 in the 2070s. In all cases, contraction exceeded expansion, although the eastern Omani highlands remained a potential climatic refugium. These patterns indicate that warming is likely to reorganize rather than uniformly expand suitability, providing a spatial basis for climate-informed biosecurity, surveillance, and regional pest management. Full article

Background: Accurate estimation of the pre-colonization interval (pre-CI), defined as the period between body deposition and initial insect oviposition, remains a challenge in postmortem interval estimation in forensic entomology. This study quantified the effects of environmental and contextual variables on blowfly oviposition timing using human cadavers. Methods: Daily photographic records from 203 donated cadavers placed at the University of Tennessee Anthropology Research Facility (March 2011–July 2014) were used to document the first observed oviposition of blowflies. Multivariable general linear models evaluated the effects of monthly temperature, black plastic coverage, and pre-placement soft tissue damage on calendar days to oviposition (IO_day) and accumulated degree days (IO_ADD). Results: Temperature was the dominant predictor, explaining substantial variation in pre-CI. Black plastic coverage significantly delayed oviposition and exhibited a temperature-dependent effect. Although soft tissue damage was associated with earlier oviposition in univariable analyses, it did not remain significant in multivariable models. Cold conditions were associated with prolonged and highly variable pre-CI. Conclusions: These findings demonstrate that temperature was the strongest predictor in this observational dataset, while contextual factors such as physical barriers modify colonization patterns. Together, they highlight the need to incorporate environmental and contextual variables into PMI estimation models and support more defensible interpretations of entomological evidence, particularly in cases involving delayed colonization or restricted insect access. Full article

Extreme summer droughts increasingly threaten freshwater biodiversity in monsoonal regions, yet community responses within heterogeneous small water bodies (SWBs) remain poorly understood. This study evaluated how drying events influence macroinvertebrate taxonomic and functional composition across different SWB types and explored the mechanisms driving post-drought recovery. We sampled isolated ponds (IPs), stream-fed ponds (SFPs), pond-linked streams (PLSs), and non-pond-linked streams (NPLSs) in Eastern China during an extreme summer drought (2022) and a subsequent recovery year (2023). Ponds exhibited high resistance, maintaining stable taxonomic and functional richness. PLSs suffered substantial summer biodiversity declines but showed rapid post-drought recovery, possibly facilitated by spatial dispersal from nearby pond refuges. In contrast, NPLSs experienced severe, lasting biodiversity loss. Drought conditions drove overall community homogenization, with spatial dispersal playing a more important role in structuring assemblages than environmental filtering. Furthermore, functional trait analysis indicated that post-drought recovery was more closely associated with resilience-linked traits rather than resistance traits. These findings demonstrate that lateral connectivity within SWB networks buffers drought impacts by providing refugial support and enabling rapid recolonization. Preserving diverse, interconnected SWBs is a critical management strategy for maintaining metacommunity resilience under growing climatic volatility. Full article

The current model of agricultural development, largely focused on the intensification of production, causes increased pressure on the natural environment and, at the same time, does not guarantee sufficient food supplies in the era of global demographic expansion. In light of current environmental changes and the escalating food shortage, the modern agricultural paradigm must strive to achieve a balance between productivity and the quality of agricultural products produced within an environmentally responsible production system. A promising and sustainable tool for future agriculture is a biorational model of agricultural production based, among other things, on the biological protection of agricultural products. The study aimed to assess the effectiveness of biological control agents containing entomopathogenic nematodes in controlling pests from the class Gastropoda. The tests showed that these preparations inhibited the feeding intensity of the analyzed pests. Among the insecticidal nematodes, the biological product containing S. carpocapsae at doses of 2000 and 4000 LJ/m² demonstrated the highest effectiveness (mass loss: A. distinctus: 0.61 g, 0.58 g; D. reticulatum: 0.60, 0.71 g). The research conducted indicates that preparations containing entomopathogenic nematodes have the potential to reduce damage caused by slugs in crops. Full article

On-farm welfare assessment of equines is a challenge given the large diversity of management practices, especially in terms of housing and activities. In our study, we tested time budget measures as a complementary tool to more conventional welfare indicators (e.g., stereotypic behaviours, ear position while foraging, neck shape). We observed 174 horses living in eight facilities (in their home environment) for which data on management practices and welfare were available. Time budget was assessed using the scan sampling method (1 min scan sampling over 30 min; 33 scans), while welfare assessment was based on classical measures. The study was performed in two parts: The first part consisted of validating time budget as a correlate of welfare state, which was performed at the individual level and according to the context of observation. In the second part, the data were analysed at the farm level by averaging data from all horses in the same facility. The results showed that the time spent feeding, in exploratory walking and observation behaviour were correlated with indicators of positive welfare and/or good practices in contrast to the time spent standing immobile resting or in fixed attention and/or in negative social interactions. Time budget varied greatly between facilities, reflecting welfare state and management (feeding, working) practices. This study shows that, provided that observations are made at different time periods when animals are calm, three sessions of 10 min. could give a good account of the local «atmosphere». These findings bring new insights into both methodological approaches and the significance of behaviours and, in particular, the importance of precisely defining and measuring the types of attention as a window into an animal’s internal state. Full article

Beyond its function as a carrier of hereditary information, recent research has uncovered novel properties of extracellular DNA, including its role in the adaptation to the environment when released from plants. The secreted DNA has been shown to exert insecticidal effects against insect pests, which play an adaptive role in plant-insect interactions, particularly in regulating populations of economically important sap-feeding insects. The molecular mechanisms underlying this insecticidal effect are underinvestigated and remain largely unknown. Therefore, there is a need for more efforts to uncover these mechanisms to better understand plant–pest interactions, which would provide new insights into natural pest control strategies and inspire biotechnological applications. In the current study, we show that Pittosporum tobira (P. tobira) secretes single-stranded DNA (ssDNA) that exerts an insecticidal effect on Coccus hesperidum (C. hesperidum). We collected extracellular DNA from P. tobira leaves and tested its potential insecticidal effect by applying it to C. hesperidum, which is a well-known pest that causes damage to P. tobira. Our results revealed that the outermost layer of the leaf cuticle of P. tobira predominantly contains ssDNA of approximately 100 nt in length, originating from both chloroplast and nuclear genomes. This DNA exhibited pronounced insecticidal activity against C. hesperidum, with chloroplast-derived sequences significantly enriched compared to the total DNA in intact plant cells. These findings suggest that the microevolution of the P. tobira nucleome and plastome contributed to the formation of extracellular DNA with insecticidal properties (eci-DNA), which is part of its defense strategy against insect pests. Moreover, in this article, for the first time, we show that antisense DNA (illustrated with oligonucleotide insecticide Coccus-11) is capable of activating insect retrotransposons and upregulating their RT-RNase H, a crucial enzyme for the DNA containment mechanism and successful action of oligonucleotide insecticides. Notably, the laboratory-developed ssDNA-based ‘genetic zipper’ technology, designed for sustainable pest management, possesses characteristics similar to eci-DNA found in nature, highlighting a potential natural parallel to this biotechnological approach for sustainable pest management. Full article

Invasive species, whose geographic distribution is expanding, seeing introduction and establishment in previously pest-free areas, have major environmental and economic impacts. The problem of invasive pests is multidimensional and complex and can only be tackled through strong integration and the use of various approaches [1]. Climate change, intense human mobility, and increased international and transcontinental trading have brought biological invasions to the forefront of the list of threats to agricultural production worldwide. Full article

While vector control methods have successfully reduced malaria rates worldwide, such methods are not always suitable for military use. We evaluated the usability, durability, and effectiveness of permethrin-treated uniforms and metofluthrin spatial repellent in preventing mosquito bites among soldiers in the Laos People’s Army that were deployed on a 12-week field exercise. The study enrolled 173 subjects into four different groups: (1) metofluthrin-only, (2) permethrin-treated uniforms, (3) metofluthrin with permethrin-treated uniforms, and (4) a control group. We measured efficacy through self-reported survey responses and a serological test for antibodies to Anopheles salivary antigens and assessed the durability of permethrin treatment over the 12-week exercise. We found that soldiers given metofluthrin and permethrin-treated uniforms were 72% and 46% more likely to report decreased mosquito bites compared to those in the control group and that soldiers with permethrin-treated uniforms had significantly lower (p < 0.05) antibody levels to the Anopheles SG6 salivary antigen. Mass spectrometry analysis revealed that treated uniforms still contained a significant permethrin concentration that showed 50 to 100% mosquito mortality. Overall, our findings show that both metofluthrin and permethrin-treated uniforms were well-tolerated and led to significantly fewer reported mosquito bites, and that permethrin, in particular, was found to be durable throughout the 12-week field exercise and effective in reducing mosquito bite exposure, underscoring its value in military applications. Full article

Maize (Zea mays L.) is a significant staple food crop in the developing world. Despite its significance, diseases and pests are limiting its supply. Farmers have primarily relied on synthetic chemicals as control measures; however, these chemicals are harmful to humans, animals, and the environment and exacerbate pest recurrence. Medicinal plants have shown promising potential as alternative pest- and disease-controlling agents, offering an economical, sustainable, biodegradable, and cost-effective approach. This review article synthesises phytochemical, ethnobotanical, and experimental data from relevant peer-reviewed papers published across various years to identify medicinal plants. Thirty-one unique plant families have been identified and have been used to control pests and diseases of maize. Some families represented both antifungal and insecticidal applications. Medicinal plants such as Senna obtusifolia, Euphorbia balsamifera, Aristolochia ringens, Allium sativum, Azadirachta indica, Carica papaya, Moringa oleifera, and Ficus exasperata have shown antifungal and insecticidal properties, primarily under laboratory conditions. Most of the evidence is derived from laboratory studies, with only limited validation in real field conditions and with limited evaluation of safety for non-target organisms. Furthermore, this review highlighted the extraction methods, solvents used, plant parts, major active ingredients, and mode of action. Future prospects for integrating ethnobotanical knowledge with contemporary scientific methods to optimise biopesticide production are also discussed, along with the challenges of standardisation, formulation, and commercialisation. Full article