Search Results (201)

Organic eggplant production in the United States is challenged by flea beetles, which stunt eggplant growth and reduce yield. Across four experiments between 2019 and 2024, we compared the effects of various pest management strategies on flea beetle abundance, damage, and marketable yield in eggplant production, focusing on row covers and organic insecticides in later years of the study. Treatments included fine-mesh row covers, organic insecticides, and untreated controls (all years); reflective plastic mulch (2019); various essential oils (2019–2020); conventional insecticide control (2019–2020); and spunbonded row covers (2019–2021). Low flea beetle pressure was observed in 2019 and 2020; consequently, experiments were moved to fields under organic management with more frequent cultivation of solanaceous crops in 2021 and 2024. Samples taken near row cover removal at flowering revealed significantly more flea beetles in the control than fine-mesh row cover treatments in 2019, 2020, and 2021. However, there were never significant differences in flea beetle abundance in samples collected at transplanting or at harvesting. Flea beetle feeding damage at flowering was significantly lower in all row cover treatments than the untreated control in 2019, 2021, and 2024 and the organic insecticide treatment in 2019 and 2021; data was not collected in 2020. There was no difference between treatments in marketable yield in 2019 and 2020; however, the marketable yields of fine-mesh row cover treatments maintained over the entire growing season were 82% and 471% higher than the organic insecticide treatments in 2021 and 2024, respectively. These results indicate that fine-mesh row covers may be a viable pest management strategy in organic eggplant production. Full article

The evolution of resistance in mosquitoes to conventional insecticides such as pyrethroids presents a challenge to vector control. Thus, alternative active ingredients for insecticides to manage pyrethroid-resistant populations of mosquitoes are needed. The goal of this study was to evaluate the toxic and repellent efficacy of geraniol, a plant secondary metabolite, as a potential alternative for controlling pyrethroid-resistant Aedes aegypti. We found that addition of geraniol to rearing water of 1st instar larvae caused concentration-dependent mortality within 24 h in both strains. The resistance ratio of geraniol (2.8) was modest compared to that of cypermethrin (435.3). Topical application of geraniol to adult female mosquitoes caused dose-dependent mortality in both strains within 24 h. The resistance ratio of geraniol (1.1) was minimal compared to that for cypermethrin (457). In spatial repellency assays, geraniol repelled adult females from both strains in a dose-dependent manner. The repellency resistance ratio of geraniol (2.6) was modest compared to that for pyrethrum extract (>132). Our findings suggest that geraniol has potential use as a toxicant and repellent for controlling pyrethroid-resistant populations of Ae. aegypti. Full article

The red imported fire ant (RIFA), Solenopsis invicta, is a globally invasive pest that causes substantial ecological, agricultural, and public health challenges. Conventional control strategies primarily depend on chemical insecticides, which present environmental risks and limited long-term efficacy. In this study, we comprehensively investigated the bacterial microbiota of S. invicta and compared it with a sympatric non-target ant species (Pheidole nodus) to explore the ecological significance and biocontrol potential of symbiotic bacteria. High-throughput 16S rRNA sequencing revealed that the symbiotic bacterial community of S. invicta exhibited markedly higher richness and diversity. A total of 1651 amplified sequence variants (ASVs) were identified, of which 1089 ASVs are unique to the RIFAs, and 460 are unique to non-target ants. Linear discriminant analysis effect size (LEfSe) highlighted 33 biomarker taxa (score > 6.5), with strong enrichment of Stenotrophomonas, Serratia, Pseudomonas, Luteibacter, Bradyrhizobium, Brucella, Smaragdicoccus, Gordonia, and Aeromonas. Functional predictions and enzymatic assays in vitro demonstrated that dominant cultivable genera, particularly Stenotrophomonas (SI-7, SI-17), Serratia (SI-1, SI-3, SI-6, SI-18), and Pseudomonas (SI-2, SI-8, SI-9, SI-11, SI-19), exhibit substantial proteolytic and lipolytic activity, suggesting key roles in nutrient metabolism and host ecological adaptability. Antibiotic susceptibility profiling further revealed that florfenicol shows broad-spectrum inhibitory activity against these dominant symbionts. These findings indicate that disrupting dominant symbiotic bacteria may impair host physiology and thus serve as a targeted control strategy. Overall, the study elucidates the diversity, functional potential, and biocontrol applicability of the S. invicta microbiome, providing a foundation for developing sustainable, microbiome-based pest management approaches. Full article

Mycterothrips glycines Okamoto (1911) (Thysanoptera: Thripidae) is rapidly increasing in fields, posing a new and potentially serious threat to soybean production in Northeast China. To clarify the population dynamics and screen effective insecticides against M. glycines, systematic monitoring and pesticide evaluation were conducted from 2024 to 2025. Occurrence dynamics were continuously monitored using yellow and blue sticky boards, while ten commonly used commercial insecticide formulations (thiamethoxam, clothianidin, sulfoxaflor, acetamiprid, imidacloprid, fenthion, pyridaben, abamectin, beta-cypermethrin, spinetoram) were hierarchically screened through laboratory bioassays, pot trials, and field spraying experiments. The results revealed a distinct ‘rise-and-fall’ occurrence pattern, with the initial, peak, and late occurrence periods occurring in mid-July, late July to early August, and mid-to-late August, respectively. Thiamethoxam and clothianidin exhibited the strongest toxicity against M. glycines (LC₅₀ values of 12.87 mg/L and 13.46 mg/L, respectively), achieving field control efficacies exceeding 85%, which were significantly superior to conventional agents such as imidacloprid and abamectin. The study identified the soybean flowering stage as the critical window for control, recommending preventive interventions when sticky trap monitoring indicates the initial population peak (around mid-July). This research fills the technical gaps regarding the occurrence dynamics of M. glycines and the lack of registered control products in China, providing essential support for precision monitoring and management of soybean thrips. Full article

The Asian citrus psyllid Diaphorina citri Kuwayama (Hemiptera: Liviidae) is the vector of the devastating citrus disease Huanglongbing, posing a significant threat to the global citrus industry and necessitating environmentally sound management strategies. This study aimed to evaluate Australian tea tree oil (TTO) and its primary constituents as potential botanical insecticides. Gas chromatography-mass spectrometry (GC-MS) was performed to analyze the chemical profile of commercial TTO, and behavioral effects on D. citri adults were assessed using a Y-tube olfactometer. Direct spray bioassays were conducted to determine contact toxicity. A total of 12 compounds were identified, with TTO being a Terpinen-4-ol chemotype, dominated by Terpinen-4-ol (40.62%), γ-Terpinene (21.46%), and α-Terpinene (10.45%). TTO demonstrated potent, concentration-dependent repellency, achieving 100% repellency at 10 g/L. In contrast, Terpinen-4-ol alone was attractive to psyllids at low concentrations, suggesting synergistic or masking effects within the complex oil blend. TTO and its major constituents also exhibited significant dose- and time-dependent contact toxicity. Although the 72 h LC₅₀ of TTO (19.18 g/L) indicates lower potency compared to conventional insecticides (0.59–1.23 g/L), its combined repellent and toxic properties make it a promising candidate for integrated pest management (IPM) programs aimed at controlling D. citri and mitigating insecticide resistance. Full article

The soybean pod borer, Leguminivora glycinivorella, is a monophagous pest that threatens soybean production. Its larvae feed concealed within pods, which limits the efficacy of conventional insecticides. Elucidating its chemosensory system is therefore essential for developing green, behavior-based management strategies. Reference-based transcriptomics across multiple tissues of L. glycinivorella identified a comprehensive repertoire of chemosensory genes, including 76 odorant receptors (ORs), 15 gustatory receptors (GRs), 18 ionotropic receptors (IRs), 52 odorant-binding proteins (OBPs), 18 chemosensory proteins (CSPs), and 4 sensory neuron membrane proteins (SNMPs). Sequence and phylogenetic analyses characterized these candidates within the context of known insect chemosensory families. Notably, canonical bitter GRs and specific IR lineages (e.g., IR100/IR85a) were not detected in our dataset, potentially reflecting adaptation to the specialized soybean-feeding habit of this pest. Expression profiling further revealed pronounced sexual and tissue dimorphism: male antennae showed significant enrichment of putative pheromone receptors (PRs) and LglySNMP1, whereas several OBPs and ORs exhibited female-biased expression, suggesting roles in host location and oviposition. Additionally, the high expression of GR43a homologs points to fructose sensing, while the lack of detectable CO₂ receptor components (except LglyGR2) suggests atypical carbon dioxide perception mechanisms. Collectively, this study provides a valuable expression atlas of chemosensory genes in L. glycinivorella and identifies sex-specific candidate genes for future functional validation and behavior-based pest management. Full article

Background: The control of fleas and ticks in companion animals is a persistent challenge with animal welfare and public health implications. The increasing resistance to antiparasitic treatments, coupled with concerns over the environmental impact and non-target effects of synthetic acaricides, has driven interest in sustainable alternatives. Essential oils (EOs) have emerged as potential candidates due to their complex chemistry and modes of action. Methods: This review critically analyzes the scientific literature on essential oils for ectoparasite control in companion animals. Specifically, it examines their chemical composition, multi-target mechanisms of action, laboratory and field efficacy, role in resistance mitigation, and integration into IPM strategies. Results: Several EOs, particularly those rich in phenolic compounds (thymol, carvacrol, eugenol, and cinnamaldehyde), demonstrate promising in vitro insecticidal and acaricidal activity. Their multi-target mechanisms, affecting neuronal, respiratory, and cuticular functions, not only provide efficacy but also represent a significant barrier to rapid resistance development. However, their translation to reliable field performance is hampered by high volatility, formulation instability, and innate variability. Conclusions: EOs represent a valuable source of bioactive compounds for reducing reliance on conventional acaricides and can play a key role within IPM strategies. To realize their full potential in mitigating resistance, focused advancements are needed in standardized testing, formulation science to enhance stability and residual activity, and rigorous field studies to confirm safety and efficacy. Full article

Essential oils (EOs) from combined plant materials offer a promising alternative to conventional extraction by enhancing chemical diversity and bioactivity. This study evaluated the chemical composition and insecticidal properties of individual and combined plant EOs from Cymbopogon citratus, Eucalyptus camaldulensis, Eucalyptus lehmannii, Salvia rosmarinus and Thymus vulgaris were evaluated against aphids. Binary and ternary combinations were prepared in equal proportions prior to hydrodistillation. GC-MS analysis revealed significant compositional shifts in EOs from combined plant materials. Major compounds in individual oils included citral (53.11%) and neral (29.14%) in C. citratus, thymol (70.84%) in T. vulgaris, and eucalyptol as the predominant compound in E. camaldulensis (66.51%), E. lehmannii (56.99%) and S. rosmarinus (46.56%), respectively. In the combined oils, the relative abundance of these constituents was altered, and in some cases new constituents were introduced. Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) revealed that combined plant EOs clustered near their parental oils, indicating compositional inheritance. Contact toxicity assay against Aphis fabae demonstrated enhanced efficacy of the combined oils, with reduced LC₅₀ values (1.39 µL mL⁻¹ for E. camaldulensis + T. vulgaris) and synergistic interactions, indicated by a co-toxicity coefficient (CTC) of 221.58 and elevated synergistic factors. Pearson correlation analysis and Partial Least Squares (PLS) regression jointly identified Acorenone B and thymol as negatively, and caryophyllene as positively correlated compounds, all with relatively high contribution to insecticidal activity, ranking highest with a Variable Importance in Projection (VIP) scores > 1.0. While PLS model had modest predictive power, the integration of these statistical approaches supports the insecticidal potential of combined plant-derived EOS in laboratory bioassays and indicates their relevance to sustainable crop protection. Full article

Abamectin is a widely used insecticide for controlling various pests, including the codling moth (Cydia pomonella). However, with the increasing emphasis on green agriculture, its potential risks to beneficial insects such as honeybees have attracted growing concern. To tackle these challenges, we established a novel nanopesticide delivery system. Specifically, a nanopesticide (Abm@TPP/CMCS) based on carboxymethyl chitosan (CMCS) cross-linked with sodium tripolyphosphate (TPP) was constructed to improve insecticidal efficacy while lowering environmental risks. The prepared nanoparticles presented a spherical and monodisperse morphology with an average size of 85.12 nm (at 0.3 mg/mL) and an encapsulation efficiency of 23.1%. Laboratory bioassays indicated that the nanopesticide exhibited significantly higher toxicity against C. pomonella (LC₅₀ = 0.371 μg/mL) than technical-grade abamectin (LC₅₀ = 0.580 μg/mL), with a corresponding toxicity ratio of 1.563. Its excellent control effect was further confirmed in field trials, with a control efficacy of 85.71% at 10 days after application, which was markedly higher than that of conventional formulations. Notably, nanoencapsulation significantly reduced environmental toxicity: the LC₅₀ value for Apis cerana increased from 0.312 μg/mL (highly toxic) for technical abamectin to 4.162 μg/mL (moderately toxic), and from 684.28 μg/mL to 1484.30 μg/mL for Eisenia fetida. In addition, the nanopesticide showed favorable biosafety toward wheat, maize, and beans, and even promoted root growth in maize. In summary, Abm@TPP/CMCS enhances insecticidal activity against C. pomonella, reduces toxicity to non-target organisms, and enables controlled release, which provides a promising strategy for eco-friendly pest management. Full article

Zeugodacus tau (Walker) is a major invasive pest that targets cucurbitaceous plants and other economically significant crops, causing substantial yield and quality losses. The pest’s method of infesting the fruit, however, limits the efficacy of conventional chemical control strategies. This study comprehensively evaluates the insecticidal efficacy of seven insecticides from two key classes—macrolides and neonicotinoids—against various developmental stages of Z. tau. Additionally, it investigates the distribution and degradation patterns of pesticide residues on sponge gourd. Laboratory toxicity tests showed notable differences in sensitivity among the three pest stages. Larvae were the most sensitive to insecticides, followed by adults, with eggs being relatively resistant. Four macrolide insecticides showed high activity against both adults and larvae, while three neonicotinoids displayed low activity against eggs, larvae, and adults of Z. tau. Field residue trials using common recommended dosages demonstrated rapid degradation of pesticide residues on sponge gourd, with residue levels dropping below the national maximum residue limits (MRLs) within 2 to 24 h after application. Further results indicated that pesticide residues accumulated mainly on the peel, with low or undetectable levels in the flesh. Among the macrolide insecticides, residues were nearly undetectable, whereas neonicotinoids, due to their systemic nature, sometimes showed trace residues in the fruit flesh. Oviposition hole measurements revealed an average depth of 0.57 ± 0.29 cm, just beneath the skin, with the hole’s structure effectively protecting the eggs laid by females. Based on the comprehensive analysis of insecticide toxicity and residue degradation, control strategies should primarily target adults. Macrolide insecticides, which have low residue risks and high efficacy against both adults and larvae, are recommended as the preferred option for management. This study, considering the unique damage characteristics of Z. tau, offers valuable insights into chemical control strategies, focusing on insecticide sensitivity at different life stages, residue distribution, and degradation, providing important references for the scientific use of pesticides and the optimization of pest management approaches. Full article

Monochamus alternatus larvae, as concealed trunk-boring pests, evade conventional insecticide contact due to their cryptic feeding niche. To overcome this limitation, previous studies have engineered strains of the naturally entomopathogenic bacterium Yersinia entomophaga. The lethality of these strains against M. alternatus was enhanced by incorporating extracellular secretion systems and enriching insecticidal proteins within the larval midgut. However, plasmid loss occurs during serial subculturing. Here, we established an engineered strain that expresses the red fluorescent protein gene mCherry to explore the applicability of bacterial conjugation transfer to Yersinia. We then constructed a chromosomally integrated strain (CSLH88-pCHSW) that incorporates extracellular secretion systems. The results of stability assays demonstrated 100% retention of the mCherry and Cry3Aa-T-HasA genes over 78 generations. SDS-PAGE and Western blot analyses confirmed the extracellular secretion of the Cry3Aa-T protein in the CSLH88-pCHSW strain. Bioassays revealed that the CSLH88-pCHSW strain was significantly more virulent against M. alternatus larvae than both the wild-type strain (CSLH88) and the plasmid-transformed strain (CSLH88-pCHKW), and exhibited markedly faster insecticidal kinetics. Our study reveals the application of bacterial conjugation transfer technology for constructing biocontrol strains. This genomically stabilized Yersinia strain eliminates the risks of failure associated with plasmid loss in the field, enabling the sustainable control of M. alternatus. Full article

A multivariate analysis system for assessing the causes of pesticide residues in organic fruit crops was developed for research on organic agriculture conducted in 2016–2017. During the project, a total of 66 organic fruit crops were examined and subjected to detailed multivariate analysis, including 25 apple, 29 raspberry, and 12 strawberry crops from various regions of Poland. Pesticide residue analysis included soil, leaves, and fruit. Pesticide residues were detected in 81.8% of the crops tested, representing 44.4% of all samples. Residues of one compound were detected in 34.8% of the crops, two compounds in 16.7%, three compounds in 18.2%, and four or more compounds in 12.1%. No residues were detected in 18.2% of the crops. The highest residue detection rate was found in soil (75.8% of crops), and the most frequently detected compounds were dichlorodiphenyltrichloroethane (DDT) isomers. Pesticide residues in leaves were found in 36.4% of crops, and in fruit in 3% of crops (2.4% of the total number of fruit samples). A total of 40 pesticide residues were detected across all samples from organic crops, including 16 fungicides and one fungicide degradation product, nine herbicides, 13 insecticides, and one synthetic repellent. Among the detected compounds, eight were withdrawn from use during the study period, and eight were not approved for use in conventional apple, raspberry, and strawberry crops. Multivariate analysis showed that in 74.2% of the crops studied, the detections concerned so-called historical compounds, in 12.1% of cases, contamination from neighbouring conventional crops, and in 39.4% of cases, the intentional use of pesticides not permitted in the organic system. Multivariate analysis indicated that the cause was deliberate use not only in the years when the samples were collected, but also in the period preceding those years. The proposed system should be regarded as a rule-based, multifactorial inference framework that integrates standard analytical methods with structured contextual information, rather than as a purely statistical multivariate model. Its conceptual structure is designed to support causal interpretation of residue findings at the crop level and could be adapted to different regulatory and geographic contexts. Full article

This study aimed to evaluate the effectiveness of a sustainable pest management program for controlling the coffee berry borer (CBB), Hypothenemus hampei, at La Catalina coffee farm (Pereira, Risaralda, Colombia) and compare it with the historical conventional control approach (2012–2022), a period during which the management of CBB was based primarily on the application of synthetic chemical insecticides. The working hypothesis was that integrating biological control agents (Phymastichus coffea, Prorops nasuta, and Beauveria bassiana) with cultural and monitoring practices would significantly reduce infestation levels and insecticide dependence while maintaining or improving economic profitability. From 2023 to 2024, GIS-based hotspot mapping, targeted parasitoid release, and fungal application triggered when infestation thresholds were reached were incorporated into sustainable pest management. Infestation, flight activity, and parasitism rates were monitored, and climatic variables were analyzed to determine their relationships with pest dynamics. The results showed that a sustainable pest management program reduced field infestation from a historical average of 3.3 ± 0.15% to 1.7 ± 0.2%, remaining below the 2% action threshold (F-test, p < 0.05). Prorops nasuta reduced the number of CBB life stages by 32.1%, falling from 10.9 ± 0.3 individuals per berry in non-parasitized fruits to 7.0 ± 0.7 in parasitized berries, while parasitism by P. coffea peaked at 70%. CBB flight activity decreased markedly compared to historical averages. The shift from a chemical approach to sustainable pest management resulted in a 26% increase in net income per hectare and a Marginal Rate of Return (MRR) of 18.06. Overall, the results confirm that a sustainable pest management program effectively suppresses CBB populations, minimizes pesticide use, and enhances the economic and environmental sustainability of coffee production systems. Full article

Bacillus thuringiensis (Bt) is one of the most extensively used microbial insecticides, attributed to the action of insecticidal crystal proteins (ICPs), primarily Cry toxins, which mediate damage to the insect midgut epithelium. Recent evidence suggests that Bt toxicity is also strongly influenced by its physiological state and interactions with the host gut environment. Biofilm formation represents an important adaptive strategy that enhances bacterial stress tolerance and may modulate insecticidal performance, although the underlying mechanisms remain unclear. However, it is still unclear how Bt in the biofilm state alters host responses at the structural and transcriptomic levels. Using the tea plantation pest Ectropis grisescens as a model, we systematically evaluated the insecticidal efficacy of biofilm-state Bt formulations and their synergistic effects with a biofilm inducer system composed of Tween-80, tea saponin, matrine, and tea polyphenols. Bioassays showed that the biofilm-state Bt supplemented with composite inducers achieved the highest corrected mortality and reduced the LC₅₀ against neonate larvae by 2.88-fold compared with conventional planktonic Bt. Histopathological, biochemical, and transcriptomic analyses further revealed that biofilm-state Bt caused more severe midgut damage and induced extensive remodeling of detoxification- and stress-response-related pathways. These findings highlight Bt physiological state as a critical determinant of formulation efficacy and provide a novel framework for Bt optimization through microbial physiological regulation. Full article

The transition to a circular bioeconomy enhances the valorization of agricultural by-products. Hawthorn leaves (Crataegus spp.), generated in large quantities from orchard maintenance, represent a promising yet underutilized biomass. This comprehensive narrative review synthesizes recent advances regarding their bioactive compounds, extraction methods, and applications. A systematic literature search was conducted to identify relevant studies. The analysis reveals that hawthorn leaves are rich in polyphenols (e.g., flavonoids, procyanidins), with their content often exceeding that found in fruits. Modern “green” extraction techniques (e.g., ultrasound- and microwave-assisted) demonstrate superior efficiency in recovering these thermolabile compounds compared to conventional methods. The broad spectrum of associated biological activities—including antioxidant, cardioprotective, neuroprotective, antimicrobial, and insecticidal effects—underpins their potential in nutraceuticals, cosmetics, and functional foods. Crucially, this review highlights the significant promise of hawthorn leaf extracts as a source for developing natural, plant-based biopesticides, aligning with sustainable agriculture and integrated pest management principles. To fully realize this “waste-to-wealth” potential, future research should prioritize the scaling of eco-friendly extraction, field trials for crop protection efficacy, and the standardization of extracts. Full article