Non-target Organisms Research Articles

Comprehensive analysis of ionomic profiling in Chlorella exposed to chlorpyrifos

IntroductionChlorpyrifos (CPF), a widely used organophosphorus insecticide, is highly toxic to non-target aquatic organisms and has relatively high persistence in water, posing a serious threat to marine ecosystems. However, little is known about the toxicological mechanism of CPF on marine microalgae, which is the main primary producer in the marine ecosystem.MethodsThis study explored the ion changes of microalgae Chlorella vulgaris under the stress of CPF through Inductively Coupled Plasma Mass Spectrometry (ICP-MS).ResultsSignificant disparities in ionomics among control and treatment group were observed through pattern recognition analysis (principal component analysis, PCA; orthogonal partial least squares discriminant analysis, OPLS-DA), indicating that CPF may impede their growth by disrupting the homeostasis of crucial elements within algal cells.DiscussionThis study elucidated the inhibitory impact of CPF on green algae growth and its potential mechanism of toxicity through ICP-MS, providing crucial insights for a comprehensive understanding of the influence of organophosphorus pesticides on aquatic ecosystems.

Oxidative DNA damage of lambda-cyhalothrin in model vertebrate organism.

Pesticides, widely used for insect control in agriculture, public health, and veterinary medicine, are usually present as pollutants in aquatic environments. After contamination of water bodies, pesticides cause adverse effects on non-target organisms and long-term problems in the ecosystem. Lambda-cyhalothrin (LCH) is a chemical compound belonging to the family of synthetic pyrethroids (type II) and is an active ingredient in several insecticides. This study investigated the toxic effects (DNA damage) of LCH exposure on zebrafish for 24 and 72 h. After zebrafish (Danio rerio) were obtained commercially, acclimated, and adapted to laboratory conditions. They were randomly selected, transferred to the experimental aquariums (their average height is 2.51 ± 0.49 cm long, 10 L aquarium size of 10x20x35), and exposed to 0.1 mg/L LCH concentrations for 24 and 72 h. There was also a control and a solvent control group in the study, and whole body tissues of zebrafish were analyzed for 8-hydroxy-2-deoxyguanosine (8-OhdG) determination (ng/100mg tissue), using an Agilent LC-MS/MS with electrospray ionization in positive ion mode. It was observed that the whole-body 8-OHdG tissuevalues were significantly increased in the group exposed to LCH for 72 h (9.82 ± 1.44) compared with the control group (6.60 ± 1.78, p = .004). These results suggest that LCH could lead to oxidative DNA damage by causing an increase in 8-OHdG activities in zebrafish, one of the aquatic ecosystem model organisms, indicating that it may also cause undesirable effects on other non-target species.

Impact of fluoxetine exposure on Lymnaea stagnalis and its developing eggs: integrating untargeted lipidomics, targeted metabolomics, and classical risk assessment

Pharmaceuticals such as selective serotonin reuptake inhibitors (SSRIs), are increasingly detected in aquatic environments, posing potential risks to non-target organisms, because many of those substances are widely shared neuromodulator. In this study, we investigated the effects of SSRI antidepressant, namely, fluoxetine, exposure on the freshwater snail L. stagnalis, focusing on egg development, neurochemical pathways, and lipid metabolism. Snails were exposed to a range of 51–434 µg fluoxetine L⁻1 for 7 days, followed by analysis of survival, feeding behaviour, reproduction, and metabolomic changes in the central nervous system (CNS), albumen gland, and eggs. Although no significant effects were observed on survival or fecundity, fluoxetine exposure significantly impaired egg development in a dose-dependent manner, reducing hatching rates with an EC50 of 126 µg fluoxetine L⁻1. Removal of eggs from the contaminated environment partially reversed these developmental effects, suggesting potential recovery if fluoxetine levels decrease. Molecular analysis revealed several neurochemical and lipidomic alterations. In the CNS, elevated levels of catecholamines, phosphatidylcholines (PC), and ceramides were linked to disruptions in neurotransmission, membrane integrity, and impaired embryo development. In the albumen gland, we detected a decrease of key lipid classes, including sphingomyelins and fatty acids, which can be linked with impaired egg quality. Additionally, a decrease in histamine in both the albumen gland and eggs suggested further disruption of egg development, potentially affecting metamorphosis success. Moreover, the dose-dependent increase in choline, along with PC and oxidized PC, indicated oxidative stress and lipid peroxidation in the CNS and exposed eggs of Lymnaea stagnalis. Our findings highlight the benefits of combining behavioral assessments with metabolomic profiling to better understand the mechanistic pathways underlying fluoxetine’s adverse effects.

Benzimidazole Fungicide Carbendazim Induces Gut Inflammation through the TLR5/NF-κB Pathway in Grass Carp.

Fungicides have been increasingly used across various sectors, including agriculture and textiles. The biocidal properties of fungicides may negatively impact the stability of intestinal microbiota, thereby posing a threat to intestinal health. In this study, we investigated the mechanisms of intestinal damage and functional abnormalities in grass carp following a 42-day exposure to the widely used fungicide carbendazim at environmentally relevant concentrations (0.2 to 20 μg/L). Histopathological observations, mRNA and protein expression analyses, biochemical analysis, quantification of short-chain fatty acids (SCFAs), cytokines, lipopolysaccharide (LPS), and 16S ribosomal ribonucleic acid (rRNA), as well as internal transcribed spacer (ITS) sequencing, were performed. At environmentally relevant concentrations, carbendazim strongly induced intestinal inflammation, leading to increased transcriptional and translational levels of genes involved in the toll-like receptor five (TLR5)/nuclear factor kappa B (NF-κB) pathway, including TLR5, NF-κB, interleukin-1 beta (IL-1β), and tumor necrosis factor-alpha (TNFα). Additionally, carbendazim damaged intestinal barriers and reduced the expression of tight junction proteins (e.g., occludin and zonula occludens-1/2), goblet cells, and immunoglobulin M levels, while also disrupting the gut microbiome, leading to intestinal metabolic disorders, particularly decreases in SCFAs and increases in LPS. Treatment with the TLR5 antagonist TH1020 mitigated intestinal inflammation caused by carbendazim, subsequently improving mechanical barrier function. Overall, our findings provide new insights into the toxicological mechanisms underlying intestinal damage caused by carbendazim in grass carp, indicating that carbendazim poses a significant threat to nontarget organisms. Given its widespread detection in the environment, these results underscore the substantial ecological risks to the gut health of fish living in carbendazim-contaminated water bodies.

Bees as environmental and toxicological bioindicators in the light of pesticide non-targeted exposure.

Pesticides have a significant impact on the environment, harming valuable non-target organisms like bees. Honeybees, in particular, are ideal bioindicators of pesticide exposure due to extensive research on how pesticides affect their behavior, immunity, development, biomolecules, and detoxification. However, wild pollinators are less studied in terms of pesticide exposure, and their inclusion is essential for a comprehensive risk assessment. Additionally, food chain organisms, such as the Asian hornet, could serve as indicators of pesticide bioaccumulation. Addressing gaps in honeybee toxicology, understanding the limitations, and exploring the role of wild pollinators and insects as complementary indicators, along with advancements in risk assessment methodologies, could enhance predictive models. These models would help anticipate environmental pesticide impacts while reducing the need for costly, time-consuming research.

Mechanistic insight into the neurodevelopmental toxicity of the novel pesticide pyrifluquinazon (PFQ) and its major metabolite in early-life stage zebrafish

Pyrifluquinazon (PFQ), a novel insecticide containing a heptafluoroisopropyl moiety, has seen increasing use. However, limited research has been conducted on the toxicological effects and mechanisms of PFQ in aquatic organisms. To investigate the toxicity and underlying mechanisms of PFQ and its primary metabolite dPFQ in aquatic organisms, morphological, behavioral, hormonal, multi-omics analyses, and molecular docking studies were conducted on zebrafish larvae after exposure. The results showed that both PFQ and dPFQ induced developmental abnormalities, behavioral impairment, hormonal disruptions, and alterations in neurologically related metabolites and gene expression in early-stage zebrafish. Notably, delayed retinal vascular development was observed, which is also likely linked to the neurodevelopmental toxicity. Subsequently, identification and relative quantification of PFQ metabolites suggested that its toxicity might be primarily attributed to dPFQ. Finally, an Adverse Outcome Pathway (AOP) was proposed, initiating with the binding of dPFQ to the TRPV4 protein and ultimately leading to neurodevelopmental toxicity. This study delineated the neurodevelopmental toxicity of PFQ and its toxicological mechanisms in zebrafish, emphasizing the hazards posed by pesticide metabolites to non-target organisms and highlighting inherent limitations of extrapolating in vitro toxicity experiments.

Photodegradation of typical psychotropic drugs in the aquatic environment: a critical review.

Continuous consumption combined with incomplete removal during wastewater treatment means residues of psychotropic drugs (PDs), including antidepressants, antipsychotics, antiepileptics and illicit drugs, are continuously entering the aquatic environment, where they have the potential to affect non-target organisms. Photochemical transformation is an important aspect to consider when evaluating the environmental persistence of PDs, particularly for those present in sunlit surface waters. This review summarizes the latest research on the photodegradation of typical PDs under environmentally relevant conditions. According to the analysis results, four classes of PDs discussed in this paper are influenced by direct and indirect photolysis. Indirect photodegradation has been more extensively studied for antidepressants and antiepileptics compared to antipsychotics and illicit drugs. Particularly, the photosensitization process of dissolved organic materials (DOM) in natural waters has received significant research attention due to its ubiquity and specificity. The direct photolysis pathway plays a less significant role, but it is still relevant for most PDs discussed in this paper. The photodegradation rates and pathways of PDs are influenced by various water constituents and parameters such as DOM, nitrate and pH value. The contradictory results reported in some studies can be attributed to differences in experimental conditions. Based on this analysis of the existing literature, the review also identifies several key aspects that warrant further research on PD photodegradation. These results and recommendations contribute to a better understanding of the environmental role of water matrixes and provide important new insights into the photochemical fate of PDs in aquatic environments.

Four Neurotoxic Insecticides Impair Partner and Host Finding in the Parasitoid Leptopilina heterotoma and Bioactive Doses Can Be Taken up Via the Host

In modern agriculture, control of insect pests is achieved by using insecticides that can also have lethal and sublethal effects on beneficial non-target organisms. Here, we investigate acute toxicity and sublethal effects of four insecticides on the males’ sex pheromone response and the female host finding ability of the Drosophila parasitoid Leptopilina heterotoma. The nicotinic acetylcholine receptor antagonists acetamiprid, flupyradifurone and sulfoxaflor, as well as the acetylcholinesterase inhibitor dimethoate were applied topically as acetone solutions. Males treated with all four insecticides no longer preferred the female sex pheromone in a T-olfactometer. Duration of wing fanning, an element of the pheromone-mediated male courtship behavior, was also reduced by all four insecticides. The ability of females to orientate towards host-infested feeding substrate was not affected by acetamiprid in the tested dose range. However, treatment with dimethoate, flupyradifurone and sulfoxaflor resulted in the loss of the females’ preference for host odor. At the lowest doses interfering with olfactory abilities of L. heterotoma in this study (acetamiprid: 0.21 ng, dimethoate: 0.105 ng, flupyradifurone: 2.1 ng and sulfoxaflor: 0.21 ng), ≥ 90% of the wasps survive insecticide treatment. Male pheromone responses and female host finding were also disturbed in those L. heterotoma that had developed in D. melanogaster larvae reared on dimethoate-treated feeding medium at sublethal levels. Hence, doses of this insecticide sufficient to interfere with chemical orientation of L. heterotoma can be taken up by the parasitoid via the food chain.

Biocontrol efficacy of Bacillus licheniformis and Bacillus amyloliquefaciens against rice pathogens.

Biocontrol is a cost-effective and eco-friendly approach to control plant pathogens using natural enemies. Antagonistic microorganisms or their derivatives specifically target the plant pathogens while minimizing the harm to non-target organisms. Bacterial blight and brown spot are the major rice diseases caused by Xanthomonas oryzae pv. oryzae (Xoo) and Bipolaris oryzae (Bo), respectively. This study was conducted to assess the plant growth-promoting potential and biocontrol activity of root-associated bacteria against the rice pathogens, Xoo and Bo. A total of 98 bacteria were isolated from rice roots and characterized for plant growth-promoting properties including phosphate solubilization, indole-3-acetic acid production, nitrogen fixation and biofilm formation. Based on these properties, 36 bacteria were selected and tested for biocontrol potential against rice pathogens via co-culturing antagonism assay. LE7 exhibited the maximum inhibition of 79%, while FR8, PE2, LE7, LR22 and LR28 also significantly reduced the growth of Xoo. Likewise, FR2, LR22, LR35 and LE7 significantly inhibited the growth of Bo, in which LR22 exhibited the maximum inhibition of 81%. Under controlled-conditions, LE7 and LR22 significantly reduced the disease incidence of Xoo and Bo, respectively, and improved the growth of rice. Full-length 16S rRNA gene sequencing of most potential bacterial isolates, LE7 and LR22, revealed their maximum identity with Bacillus amyloliquefaciens and Bacillus licheniformis, respectively. Application of Bacillus spp. as biocontrol agent represents enormous potential in rice farming. The most promising bacterial isolates could be used as bioinoculants for rice disease management and improved production in a sustainable manner.

Botanicals for managing insect pests in rice: An eco-friendly strategy for sustainable rice production

Rice, a staple crop for over half the global population, faces severe yield losses due to insect pests, such as the rice stem borer (Scirpophaga incertulas), brown planthopper (Nilaparvata lugens) and leaf folder (Cnaphalocrocis medinalis) and minor insect pests, which are significant threats to global food security. Traditional reliance on chemical pesticides for pest control has negatively impacted the environment, human health and non-target organisms. This has necessitated a shift toward sustainable pest management strategies that minimize chemical inputs. Botanicals, derived from plants as essential oils, extracts and secondary metabolites, have emerged as an eco-friendly alternative due to their biodegradability, targeted efficacy and reduced environmental footprint. These plant-based compounds act through various mechanisms, including antifeedant activity, growth inhibition, oviposition deterrence, ovicidal effects and toxicity, effectively disrupting pest lifecycles without harming non-target species. Studies underscore the potential of botanicals in suppressing pest populations and mitigating crop losses, making them vital components of Integrated Pest Management (IPM) strategies. When incorporated into IPM programs alongside biological control agents, cultural practices and resistant rice varieties, botanicals enhance pest control efficacy while preserving ecosystem balance and promoting biodiversity. Their use aligns with sustainable agriculture principles, offering a viable path to reduce pesticide dependency and ensure long-term agricultural resilience. This review highlights the critical role of botanicals in IPM for rice cultivation, emphasizing their potential to mitigate pest impacts while supporting environmentally sustainable and economically viable food production systems.

Nanoization of Technical Pesticides: Facile and Smart Pesticide Nanocapsules Directly Encapsulated through "On Site" Metal-Polyphenol Coordination Assembly for Improved Efficacy and Biosafety.

Facile pesticide nanocapsules were successfully prepared by directly encapsulating the antisolvent precipitation of pesticides through instantaneous "on site" coordination assembly of tannic acid and Fe3+, avoiding tedious preparation, time consumption, and large amounts of organic solvents. The pesticide nanocapsules showed excellent resistance to ultraviolet photolysis and rainwater washing owing to the nanocapsule walls. The smart pesticide nanocapsules exhibited the controlled release of pesticides under multidimensional stimuli, such as acidic/alkaline pH, glutathione, H2O2, phytic acid, laccase, tannase, and sunlight, which were related to the physiological and natural environments of crops, pests, and pathogens. The tebuconazole nanocapsules not only enhanced the fungicidal activity against Fusarium graminearum and effective control efficacy in wheat powdery mildew through foliar spray and seed coating, but also improved the biosafety of target plant growth and nontarget organisms. The facile, smart, efficient, safe, and green pesticide nanocapsules using the universal strategy have broad application prospects in ecoagriculture.

Fabrication of Multifunctional Three-Component Supramolecular Nano-Biscuits via Two Macrocycles-Involved Self-Assembly for Rice, Citrus and Kiwifruit Protections.

Bacterial plant diseases, worsened by biofilm-mediated resistance, are increasingly threatening global food security. Numerous attempts have been made to develop agrochemicals that inhibit biofilms, however, their ineffective foliar deposition and difficulty in removing mature biofilms remain major challenges. Herein, multifunctional three-component supramolecular nano-biscuits (NI6R@CB[7]@β-CD) are successfully engineered via ordered self-assembly between two macrocycles [cucurbit[7]uril (CB[7]), β-cyclodextrin (β-CD)] and (R)-2-naphthol-based bis-imidazolium bromide salt (NI6R). This macrocycles-involved bactericidal material combines many advantages. 1) Alleviate the off-target movement of droplets on hydrophobic blade surfaces. 2) Enhance the biofilm-disrupting ability. At a low-dose of 4.44µg mL-1, the inhibition rate of biofilm formation reached 78.3%. At 35.5µg mL-1, the potency to remove mature biofilms reached 77.6%. 3) Efficiently hinder bacterial reproduction, swimming, extracellular polysaccharide production, extracellular enzyme secretion, and virulence to plants. These superior characteristics are undoubtedly transmitted to the in vivo control effect. At 200µg mL-1, this smart material exhibits superior control efficiencies of 49.6%/65.0%/85.4% against three kinds of bacterial diseases (rice leaf blight, citrus canker, and kiwifruit canker), respectively, surpassing the commercial bactericide-thiodiazole-copper-20%SC (33.6%/41.5%/43.2%) and NI6R (40.3%/51.2%/71.2%). Furthermore, NI6R@CB[7]@β-CD is biosafe to non-target organisms. This study is instructive for constructing multifunctional agrochemicals in sustainable crop protection.

The Cry2Aa protein is not enough to pose a threat to Pardosa astrigera.

The widespread commercialization of genetically modified (GM) crops makes it important to assess the potential impact of Bacillus thuringiensis (Bt) on non-target organisms. Pardosa astrigera is an important predator in agroforestry ecosystems, and female and male spiders may react differently to Bt toxins due to their different activity habits and nutritional requirements. In this study, we found that exposure to Cry2Aa protein did not affect the survival and body weight of P. astrigera during growth and development. However, according to 16S rRNA sequencing results of the P. astrigera adults, Cry2Aa protein not only changed the diversity of symbiont bacteria, but also changed its symbiont composition. During feeding on prey without Bt artificial feed, the dominant communities in female and male adults were Actinobacteria and Corynebacterium-1, respectively. Feeding on prey containing Cry2Aa protein, Firmicutes were the dominant phyla. At the genus level, Cry2Aa protein significantly increased the relative abundance of Enterococcus and became the dominant genus in females only. In addition, Bacillus, Weissella and other symbiotic bacteria had significant changes in females. In terms of species composition, sex differences resulted in the absence of different types of symbiotic bacteria. Functional analysis of enrichment pathways showed significant changes in various metabolic pathways such as "Carbohydrate metabolism" and "Nucleotide metabolism", and there are differences between the sexes. These findings provide new data information and support for revealing the different strategies of spiders to cope with Cry2Aa protein based on sex differences, and also provide new data information and support for environmental safety assessment of GM crops.

Evaluating point source pesticide contamination via sprayer washing water dispersal: A northern Italian vineyard area case study.

Wastewater contaminated by plant protection products (PPP) from sprayer cleaning operations must be properly managed and disposed of, as it could represent a point source of environmental PPP pollution and pose risks to non-target organisms. Three conventionally and two organically managed farms in hilly vineyards of North-West Italy engaged in a participatory activity for sampling sprayer washing and resultant water. In total 52 samples of wash water (internal and external) were collected during two agricultural seasons and analyzed for six organic pesticides and metallic Cu. PPP concentrations in water collected after internal washing were up to 37.9 times higher than in water collected after external washing. Concentrations in water after external washing were surprisingly high. This may be explained by the characteristics of the sprayers, but also by farmers failing to comply with good practices during PPP use. To evaluate the possible impact on the aquatic environment of dispersal of wash water into a water body, the FOCUS "Stream" approach was followed. The concentrations thus estimated were almost always higher than the environmental quality standard for surface waters but below the toxicological endpoints for fish and Daphnia magna. With reference to the Italian guidelines for waste classification, only one sample would be classified as ecotoxicological hazardous waste and need to be properly managed. In conclusion, due to the nature of contamination, which is point source but diffuse in the territory, analytical data confirms the need for additional joint efforts to improve awareness in managing wastewater containing PPP and to decrease the impact of the agricultural sector.

Ecotoxicological impact of succinate dehydrogenase inhibitor (SDHI) fungicides on non-targeted organisms: a review.

As the global population continues to grow, the use of pesticides to increase food production is projected to escalate. Pesticides are critical in plant protection, offering a powerful defense against fungal diseases such as apple scab, leaf spot, sclerotinia rot, damping off, sheath blight, and root rot, which threaten crops like cereals, corn, cotton, soybean, sugarcane, tuberous vegetables, and ornamentals. Succinate Dehydrogenase Inhibitor (SDHI) fungicides represent a novel class essential for controlling fungal pathogens and bolstering food security. However, the impact of SDHIs on non-target organisms, including freshwater and terrestrial invertebrates, crustaceans, and oligochaetes, remains insufficiently understood. Empirical studies indicate that SDHIs can induce mortality, mitochondrial dysfunction, oxidative stress, and developmental delays in non-target organims. Additionally, the environmental persistence of these compounds raises concerns about their potential for ecological disruption. The effects of SDHIs on pollinating species and the possible transgenerational transmission of harmful effects warrant further investigation. Comprehensive transcriptomic analyses are necessary to elucidate the molecular disturbances and adverse outcome pathways triggered by SDHIs. Furthermore, there are emerging concerns about the endocrine-disrupting potential of SDHIs in aquatic organisms. For the first time, this review aims to synthesize existing knowledge on the ecotoxicological impacts of SDHIs on non-target organisms and identify critical research directions to address the ecological challenges posed by their use.

Exploring chitin metabolite profiles and sensitivity differences in Collembola species exposed to teflubenzuron.

Effective environmental risk assessments of chemical plant protection products, such as benzoylurea pesticides, are crucial for safeguarding ecosystems. These pesticides, including teflubenzuron, target chitin synthesis in arthropods but also pose risks to non-target soil fauna like Collembola, which play essential roles in decomposition and nutrient cycling. This study combines traditional toxicity tests with a metabolomic approach to examine the interspecies specific sensitivity of three Collembola species - Sinella curviseta, Ceratophysella denticulata, and Folsomia candida - to teflubenzuron. The investigation focused on reproduction, bioaccumulation, and changes in chitin-related metabolites as indicators of pesticide impacts. Results revealed significant interspecies specific variability in sensitivity, with F. candida showing higher susceptibility towards teflubenzuron, possibly due to greater bioaccumulation factors. Metabolomic analysis highlighted distinct patterns in chitin metabolite alterations among the species, correlating with their differential sensitivity. Notably, metabolites like trehalose and glucose, crucial for chitin synthesis, were significantly affected by teflubenzuron within seven days of exposure. Despite high soil concentrations of the pesticide, S. curviseta demonstrated resilience in traditional life-history endpoints, such as reproduction and survival. However, metabolomics indicated a biochemical response to even low internal concentrations of teflubenzuron, underscoring the complexity of their interactions with environmental stressors. This study emphasizes the importance of incorporating metabolomics to understand the differential responses of non-target organisms to pesticides and advocates for species-specific risk assessments in pesticide regulation. The distinct metabolic responses among Collembola species to chitin synthesis inhibitors provide critical insights into their ecological resilience or vulnerability, enhancing our understanding of ecosystem dynamics and the potential ramifications of chemical exposure.

Floral Resource Integration: Enhancing Biocontrol of Tuta absoluta Within Sustainable IPM Frameworks

The tomato leaf miner, Tuta absoluta, is a pest threatening global tomato production. This pest’s adaptability and resistance to chemical insecticides have necessitated integrated pest management (IPM) strategies prioritizing sustainable alternatives. This review explores the role of biological control agents (BCAs) in managing T. absoluta populations, emphasizing the integration of floral resources to enhance their efficacy. Predatory mirids such as Macrolophus pygmaeus and Nesidiocoris tenuis and parasitoids such as N. artynes and Trichogramma spp. are pivotal in pest suppression; however, their performance depends on nutritional and habitat support. Floral resources provide essential sugars and proteins, improving the longevity, fecundity, and predation efficiency of these BCAs. This review synthesizes case studies highlighting the benefits of selected flowering plants, such as Lobularia maritima and Fagopyrum esculentum, in supporting predator and parasitoid populations while minimizing advantages to T. absoluta. Mechanisms such as nectar quality, floral accessibility, and spatial–temporal resource availability are explored in detail. Additionally, the challenges of selective floral attraction, microbial impacts on nectar composition, and the unintended support of non-target organisms are discussed. This review proposes targeted floral management strategies to optimize BCA performance within IPM systems by integrating ecological and chemical insights. This approach offers a pathway toward reducing chemical pesticide reliance, fostering sustainable agriculture, and mitigating the economic impacts of T. absoluta infestations.

Evaluation of hesperidin as a potential larvicide against Culex pipiens with computational prediction of its mode of action via molecular docking

Hesperidin, a natural flavanone glycoside predominantly found in citrus fruits, has gained attention for its wide-ranging biological activities, including potential insecticidal properties. Culex pipiens, commonly known as the northern house mosquito, is a major vector of several human pathogens, such as the West Nile virus and filariasis, making it a key target in the fight against vector-borne diseases. In this study, we evaluated the larvicidal activity of Hesperidin against Culex pipiens larvae, assessing its potential as an alternative to chemical insecticides. Hesperidin demonstrated potent larvicidal effects, with a lethal concentration 50 (LC50) of 570.3 ± 0.04 µg/mL, outperforming the conventional insecticide Chlorpyrifos 588.3 ± 0.28 µg/mL in efficacy. Molecular docking simulations revealed a strong binding affinity between Hesperidin and crucial neuroreceptors in Culex pipiens, particularly acetylcholinesterase (AChE), a key enzyme involved in nerve signal transmission. The interaction between Hesperidin’s hydroxyl groups and the AChE enzyme’s active site suggests that AChE inhibition is the primary mechanism driving Hesperidin’s insecticidal action. These findings position Hesperidin as a promising, environmentally friendly alternative to synthetic insecticides. However, further research is needed to assess its toxicity to non-target organisms and optimize its formulation for broader application in mosquito control.

Impact of glyphosate herbicide exposure on sperm motility, fertilization, and embryo-larval survival of pejerrey fish (Odontesthes bonariensis).

The herbicide glyphosate is widely used in agricultural practices around the world, can reach aquatic environments, and potentially impact non-target organisms. This study aimed to investigate the effects of glyphosate exposure (both as the active ingredient and its formulated product) on sperm quality, fertilization success, and development of pejerrey (Odontesthes bonariensis), a native freshwater fish species from Argentina. Results revealed a statistically significant increase in sperm motility at the highest concentration of the formulated product. In contrast, exposure to the active ingredient resulted in a decrease in certain motility parameters. Fertilization assays and embryonic development showed no notable effects in exposed groups. There were no effects in the morphology or temporal evolution of the embryonic stages, nor in the hatching rate. In contrast, larvae exposed to the formulated product exhibited a significant increase in mortality rates, reaching 100% mortality at the highest concentration within a few hours. These findings suggest differential susceptibility between embryos and larvae to glyphosate exposure and highlight the importance of simultaneously assessing the impacts of both the active ingredient and the entire formulation of glyphosate on freshwater fish reproduction and development.

Enhanced Mosquito Larvicidal Efficacy and Dehairing Properties of Bacillus thuringiensis Serovar israelensis Strain VCRC-B649 Isolated from Malabar Coast, India.

In recent years, there has been a global threat from emerging vector-borne diseases (VBD), despite the implementation of several vector control programs. Considering the benefits of bacterial pesticides, the present study aimed to isolate potential mosquitocidal bacteria from the various soil types collected from the Kasaragod (12.5°N, 75.0°E) district of Kerala, India. One bacterial strain was isolated from the coastal alluvium soil and showed promising mosquitocidal activity. The mosquitocidal isolate was identified as Bacillus thuringiensis serovar israelensis strain VCRC-B649 through phylogenetic analysis of whole genome sequence. LC50 values against Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi larvae were determined as 0.0064, 0.0072, and 0.0101mg/L, and LC90 values were 0.0127, 0.0140, and 0.019mg/L. Comparative analysis of larvicidal activity of this strain has revealed more efficacy than the WHO reference strain of B. thuringiensis var. israelensis (H14) The cry and cyt gene profile of this isolate is found to be similar to WHO reference strain of B. thuringiensis var. israelensis (H14). This new isolate has not shown any adverse effects against aquatic non-target organisms. Further evaluation of its morphological, biochemical characteristics and growth kinetics revealed similarities with already reported B. thuringiensis strains. Sporulated culture at 72h showed maximum (20.6 ± 1.5mm) proteolytic activity and animal skin (goat skin) dehairing property and revealed the industrial applications of this new strain. This is the first report on the isolation of mosquitocidal bacterial strain with enzyme-producing property from the Malabar coastal region and it was proven to be a more suitable alternative biocontrol agent for controlling the disease transmitting mosquito vectors with translational value.