Pine wilt disease, caused by the pinewood nematode Bursaphelenchus xylophilus, poses a serious threat to pine forests worldwide, yet the hormonal and metabolic mechanisms that determine whether a pine species succumbs to or tolerates infection remain poorly understood. Jasmonic acid (JA) signalling is a central defence pathway in plants, but its precise contribution to species-dependent resistance in Pinus has not been systematically evaluated. This study dissects how targeted activation and inhibition of the JA signalling pathway remodel defence responses and nematode infection dynamics in three pine species with contrasting susceptibility to the pathogen (from most to least susceptible, Pinus pinaster, P. pinea, and P. taeda). Seedlings were treated with methyl jasmonate (MeJA) or the jasmonate inhibitor sodium diethyldithiocarbamate (DIECA) before nematode inoculation, and effects on symptom development, nematode colonisation, primary and secondary metabolism, oxidative stress, phytohormone profiles, and defence-related gene expression were assessed. P. pinaster developed clear symptoms and a marked increase in nematode numbers, whereas P. pinea and P. taeda remained largely asymptomatic. In P. pinaster, MeJA reduced both symptom severity and nematode proliferation, while DIECA impaired early defence activation although a delayed compensatory response was detectable. Across species, nematode infection triggered significant increases in phenolic compounds, flavonoids, and carotenoids, particularly in P. pinea, highlighting the contribution of secondary metabolism to plant resistance to the pinewood nematode. Overall, untreated infected plants showed higher lipid peroxidation compared with MeJA-treated, and phytohormone analyses revealed species-specific regulatory patterns. Gene expression patterns confirmed activation of phenylpropanoid and terpenoid pathways, with PAL, GGPPS, and MYC2 showing species- and treatment-specific regulation. Together, these results are consistent with the existence of distinct regulatory architectures underlying susceptibility versus tolerance, and provide hormonal, metabolic, and transcriptional profiles that may inform future breeding and priming strategies against pine wilt disease, though further functional validation will be needed to establish causation.
Sex pheromone-based mass trapping is a key strategy for managing the rice stem borer, Chilo suppressalis. However, its efficacy is often compromised by limited horizontal diffusion of the pheromone plume during hot, windless summer conditions. This study investigated how trap geometry and microclimate interact to influence sex pheromone plume dynamics in the lab and, consequently, trapping success in the field. Using titanium tetrachloride smoke as a tracer to visualize the airflow carrying the odor, we compared a traditional cylindrical trap (Type A, with 22 top apertures) against a modified trapezoidal design (Type B, with 4 top apertures; Type C added interlocking parts) under controlled wind (0, 0.8, 1.5 m/s) and temperature (25 °C, 40 °C) conditions. Laboratory simulations revealed that high temperatures (40 °C) promote vertical escape of the smoke plume, especially from Type A traps with numerous top apertures, reducing horizontal dispersion. In contrast, the Type B trapezoidal design, particularly with sealed or fewer top apertures, significantly enhanced lateral plume spread under warm, low-wind conditions by promoting a more horizontal effluent trajectory. Consistent with these aerodynamic principles, the field results demonstrated strong context-dependency. Trials conducted across multiple seasons and regions confirmed the capture performance. During hot summer periods (July–August) with low wind speeds, Type B traps captured 6.9–7.5 times more moths than Type A traps. Furthermore, traps with 1–8 top apertures caught significantly more moths than those with 9–19 apertures. Performance differences between trap types diminished under cooler, windier conditions. We conclude that optimizing trap geometry is critical for adapting pheromone traps to local microclimates. Specifically, adopting a trapezoidal shape and minimizing top apertures substantially improving their resilience and efficacy in challenging hot, calm environments typical of rice-growing regions.
The greater wax moth Galleria mellonella is a ubiquitous pest in beekeeping practice, causing direct damage to wax combs and brood while also suspected to act as a mechanical vector for honey bee pathogens such as Nosema ceranae. To evaluate vectoring potential and the influence of inoculation route, dose, and host genetic background on infection outcomes, we established a controlled hive model comparing oral inoculation (OI) and food inoculation (FI) across a range of N. ceranae spore doses in three genetically distinct G. mellonella lines and Apis mellifera carnica workers. Using equal spore doses (1.8 × 104 to 11.25 × 106), FI resulted in significantly lower spore ingestion than OI at all doses above the lowest (p = 0.0001), with a mean 7.09-fold reduction in spore load. After adjusting FI doses sevenfold higher (1.26 × 105 to 78.75 × 106), no significant differences in spore loads were detected between groups. Survival analysis revealed that N. ceranae significantly reduced baseline survival, with one G. mellonella line exhibiting dose-dependent mortality while two lines showed resistance. When co-incubated with infected honey bees in an artificial hive environment, the susceptible moth line experienced complete mortality by day 10, whereas honey bee survival remained unaffected. These findings demonstrate that while G. mellonella can acquire N. ceranae, infection success depends critically on exposure route, dose, and host genetic background. Accelerated mortality in susceptible moth lineages likely limits their capacity to act as effective vectors, suggesting that particular individuals within G. mellonella population play a limited role in secondary pathogen spread compared to its direct pest effects.
Tomato leaf miner, Tuta absoluta (Meyrick), is among the most destructive invasive pests of tomato worldwide, with chemical insecticides remaining central to its control despite widespread resistance development. Intensive and often uncoordinated insecticide use has driven resistance evolution across multiple modes of action, highlighting the urgent need for more consistent and reliable resistance monitoring approaches. In this review, we summarize the major bioassay methods used to assess insecticide resistance in T. absoluta, including primarily leaf-dip assays together with topical, residual film, and diet-incorporation approaches. We discuss their strengths, limitations, and suitability for resistance monitoring programs. The review also examines key approaches used in dose–response analysis, such as LC50 and LC90 estimation, resistance ratio calculations, and the application and evaluation of diagnostic concentrations (DCs) based on baseline susceptibility data. Findings from synergist bioassays and validated target-site mutations are also discussed to explain the biochemical and genetic basis underlying resistance phenotypes. Special attention is given to the practical use of diagnostic concentrations for large-scale resistance surveillance and decision-making in the field. We further discuss how DC-based monitoring can support insecticide resistance management (IRM) programs through insecticide rotation, reduction of selection pressure, and integration with biological control strategies. Finally, we highlight emerging tools, including molecular diagnostics, RNAi-based technologies, and regional monitoring networks, as promising approaches for improving resistance surveillance. Overall, this review synthesizes current knowledge on resistance monitoring and management strategies for T. absoluta.
Spodoptera frugiperda (J. E. Smith) is a globally invasive pest that poses significant threats to a variety of crops. It has a wide host range of more than 353 recorded plants from 76 families. However, the herbivorous insects could have adaptation mechanisms through physiological modifications in response to constitutive defenses of different host plants. The results revealed that feeding different host plants could significantly affect LC50s of broflanilide, chlorantraniliprole, tetraniliprole, indoxacarb, metaflumizone, lufenuron, methoxyfenozide, and spinetoram to S. frugiperda compared to rearing on Zea mays (L.). Detoxification enzyme activity assays and synergist tests indicated that changes in detoxification enzyme activity cause alterations in the susceptibility of S. frugiperda to insecticides. Knockdown of UGT40F3 using RNA interference (RNAi) significantly increased susceptibility to tetraniliprole in all host-fed strains. Microscale thermophoresis (MST) and molecular docking revealed a robust tetraniliprole-UGT40F3 interaction, suggesting that UGT40F3 plays a pivotal role in tetraniliprole metabolism. These results showed that different host plants can influence the detoxification enzyme activity of S. frugiperda, leading to variations in its susceptibility to insecticides. These findings provide a scientific foundation for developing effective pest management strategies.
The bluegreen aphid (Acyrthosiphon kondoi) is a global pest of pasture and legume crops, damaging plants through feeding and the transmission of plant viruses. Since 2018, Australian growers have reported insecticide control failures involving A. kondoi, with subsequent bioassays confirming the first cases of insecticide resistance in this species worldwide. To better inform management strategies, we conducted a surveillance programme of 36 field populations across southern Australia, testing for resistance to organophosphates, carbamates, and synthetic pyrethroids. Resistance was detected in 19 populations, most commonly within alfalfa (Medicago sativa) seed production regions. We then generated baseline sensitivity data for two insecticides, sulfoxaflor and flonicamid, recently introduced for A. kondoi control in Australia, and found that both provide promising new options for resistance management. In parallel, we assessed biological control potential by surveying parasitoid wasps attacking A. kondoi. Aphidius ervi was the only species detected parasitising A. kondoi across southern Australia. Follow-up laboratory assays demonstrated high parasitism and successful emergence of A. ervi from A. kondoi and more variable performance across co-occurring aphid pests, highlighting its broader biocontrol potential in pasture and legume systems. Together, these findings demonstrate the rapidly expanding distribution of insecticide resistance in A. kondoi, confirm the value of newly available insecticides, and identify a key parasitoid for integration into management strategies. These findings provide a foundation for integrated management approaches to slow resistance evolution in A. kondoi in Australia and elsewhere.
Essential oil components such as terpenes, terpenoids and phenylpropanoids are promising active substances for development of new botanical insecticides. The objective of this study was to identify the insecticidal effectiveness of five major essential oil components and their binary mixtures against Metopolophium dirhodum (Walker) (Hemiptera: Aphididae), an important cereal pest. For the tested compounds, probit analysis was employed to estimate LC50(90) at 2.32 (8.99) mL L−1 for citral, 1.07 (4.65) mL L−1 for eugenol, 0.91 (2.47) mL L−1 for geraniol, 2.65 (11.74) mL L−1 for geranyl acetate and 2.20 (7.51) mL L−1 for terpineol. Phytotoxicity for experimental plants of Triticum aestivum L. was proven for citral, eugenol and geranyl acetate at concentrations equalling the estimated LC90 for M. dirhodum. Geranyl acetate was shown to be an important synergist with all the other tested compounds. The best insecticidal effect was observed in the binary mixture of geranyl acetate/terpineol (1:1 ratio), for which the LC50(90) was estimated at 0.97 (3.72) mL L−1; at the same time, no phytotoxicity to the experimental plants of T. aestivum was observed. This binary mixture also turned out to be very friendly to the larvae of Aphidoletes aphidimyza Rondani (Diptera: Cecidomyiidae) and Chrysoperla carnea Stephens (Neuroptera: Chrysopidae), two important aphid predators. Our results show that the geranyl acetate/terpineol mixture is a promising candidate for the development of environmentally friendly botanical insecticides against aphids.
The integration of physical and biological control is a cornerstone of integrated pest management and sustainable agriculture. However, the compatibility between physical agents, such as mineral oils, and natural enemies remains a critical challenge due to potential behavioral interference. This study aimed to develop a coordinated strategy to harmonize the use of mineral oils and the predatory lady beetle Harmonia axyridis against the mealybug Planococcus minor. Among tested physical control agents, nC24 mineral oil was identified as the optimal agent due to its high lethal efficacy against reproductive adults of P. minor and relative safety for H. axyridis. Although the predator exhibited a Type II functional response, behavioral tracking analysis revealed that wet oil residues significantly disrupted its foraging efficiency, reducing movement speed by 30
Long-term insecticide resistance monitoring is essential for sustainable management of the pink bollworm (PBW), Pectinophora gossypiella (Lepidoptera: Gelechiidae), in cotton. We present 13–15 years of field data from Israel, where Pima (Gossypium barbadense, Malvales: Malvaceae) -Bt (Bacillus thuringiensis) cotton is not available; therefore, chemical control remains the primary management tool. Resistance was assessed in adults collected from cotton fields and compared with a susceptible laboratory strain. Reference-line probit analyses identified chlorpyrifos, bifenthrin, and methomyl as the most potent compounds, with cypermethrin the least effective. Resistance ratios in field populations were 15-fold for cypermethrin, 20-fold for chlorpyrifos, and 45-fold for bifenthrin; no resistance to methomyl was detected. Despite moderate resistance levels, field control was sometimes ineffective, likely due to localized high-resistance populations or suboptimal application methods. Temporal trends showed increasing survival at diagnostic doses for both pyrethroid compounds. Reliance on broad-spectrum insecticides has declined following the phase-out of key organophosphates, accompanied by a growing emphasis on integrated pest management (IPM); approaches such as area-wide control, mating disruption, drone-applied SPLAT-PBW (a compound containing PBW female pheromone) sprays, and post-harvest residue destruction are increasingly implemented. These results underscore the importance of continued surveillance, the integration of non-chemical tactics, and the evaluation of new insecticides with minimal environmental and human health risks to sustain PBW control in Israeli cotton systems.It should be Rami A. Horowitz
Aphids (Hemiptera: Aphididae) are important phloem-feeding pests in global agriculture, and their interactions with plants constitute a typical coevolutionary system involving complex molecular signaling, behavioral regulation, and ecological effects. Aphid–plant interactions can be viewed as a dynamic “arms race” that determines plant resistance levels and aphid adaptive capacity. This review systematically summarizes plant defense mechanisms and aphid counter-defense strategies: plants perceive aphid invasion via pattern recognition receptors and resistance proteins, which activate defense signaling pathways mediated by salicylic acid (SA) and jasmonic acid (JA). In turn, aphids suppress or evade plant defenses by modulating feeding behavior, secreting salivary effectors, undergoing metabolic adaptation, and relying on symbiont assistance. Despite substantial advances to date, current understanding of aphid–plant interactions remains fragmented across molecular, ecological, and environmental hierarchical scales. Knowledge gaps are especially prominent concerning interactive impacts of aphid effectors, endosymbionts, fluctuating environmental conditions, and plant virus transmission. This review delivers an integrated, holistic synthesis bridging molecular mechanisms and ecological consequences. Additionally, the regulatory roles of environmental factors—including temperature, CO2 concentration, light, water availability, natural enemy pressure, and viral infection on the outcomes of these interactions. It also highlights the potential applications of these insights in aphid-resistant crops, developing RNAi-based control methods, and designing ecological management strategies. A deep understanding of the multilayered mechanisms underlying aphid–plant interactions helps reveal coevolution patterns and provides a theoretical foundation and potential genetic resources for developing novel, environmentally friendly, and sustainable aphid management strategies. Overall, we establish an integrated framework showing that aphid–plant interplay is governed by combined influences of plant defenses, aphid counter-defenses, symbionts, plant viruses and environmental factors, yielding fresh insights for sustainable aphid control.
The oriental fruit fly, Bactrocera dorsalis, is a devastating pest in global horticulture, yet the relentless rise of insecticide resistance has steadily undermined conventional control measures. While microbial biocontrol agents offer an environmentally benign alternative, their efficacy is constrained by the host innate immune system. Here, we present a strategy to overcome this limitation by using RNA interference (RNAi) to suppress host immune defenses, thereby improving the pathogenicity of an indigenous gut bacterium. From naturally deceased B. dorsalis individuals, we isolated Serratia marcescens, a Gram-negative pathogen capable of stable gut colonization and inducing significant adult mortality. Infection with S. marcescens activated the Imd immune pathway, and RNAi-mediated silencing of BdDpt increased bacterial load in the hemolymph. To enable oral delivery, we employed chitosan nanoparticles to protect dsRNA from gut nucleases and incorporated dsRNase silencing to prolong RNAi activity. In cage and semi-field trials, the combination of S. marcescens with nanoparticle-encapsulated dsRNA targeting both BdDpt and RNases achieved 70.4
Wheat aphids represent a major constraint to sustainable cereal production, yet their control remains largely dependent on chemical insecticides, with well-documented ecological and resistance-related drawbacks. Diversifying crop habitats using functional plants offers a promising alternative, but the relative effectiveness of different spatial configurations and their mechanistic links to pest regulation and yield remain poorly resolved. Here, we conducted a two-year field experiment to assess how contrasting pea-based field layouts influence wheat aphids (Sitobion avenae and Rhopalosiphum padi), their natural enemies, arthropod community structure, and wheat yield. Four treatments were compared: a blank control, conventional management, pea intercropping, and pea circle cropping. Aphid and natural enemy dynamics, community diversity indices, and yield components were quantified, and structural equation modeling was used to disentangle direct and indirect effects of field layout on pest regulation and yield formation. Both pea-based layouts significantly reduced mean densities of R. padi, while responses of S. avenae varied between years. Pea intercropping and circle cropping consistently increased the abundance of natural enemies, particularly parasitoids, and enhanced arthropod community diversity and evenness. Natural enemies were strongly aggregated in pea strips, highlighting their role as functional habitats. Wheat yield was significantly higher in pea-based systems than in the untreated control, with pea circle cropping delivering the most stable and highest yields across years. Structural equation modeling revealed that pea layouts were positively associated with yield, primarily through increased natural enemy abundance and reduced aphid pressure. Overall, our results demonstrate that spatial configuration of functional plants is an important factor influencing aphid and natural enemy dynamics in wheat systems. Pea circle cropping, in particular, represents an effective ecological intensification strategy that was associated with lower aphid abundance, supports beneficial arthropod communities, and stabilizes crop yield, offering a practical pathway toward reduced pesticide reliance in cereal agroecosystems.
Developmental temperature strongly affects insect body size, a key trait for the performance of predators used in augmentative biological control. The anthocorid Orius laevigatus is widely released against thrips in greenhouse crops, and larger individuals show higher fecundity and predation capacity. Here, we analyze how thermal history across generations shapes adult size in this predator, combining genetic improvement and phenotypic plasticity. We compared two cold-tolerant lines of O. laevigatus, previously selected for enhanced performance at low temperature, with a commercial strain. Lineages were reared for four successive generations under combinations of 15 and 26 °C, and pronotum width of adults from the last generation was measured as a proxy of body size. Cold-selected lines were consistently larger than the commercial strain across all treatments, confirming a strong genetic component to size. Developmental temperature in the last generation had the largest effect, with individuals reared at 15 °C being larger than those reared at 26 °C. In addition, exposure of parents, grandparents, and great-grandparents to 15 °C increased the size of descendants, revealing a clear but gradually declining transgenerational effect. However, multiple consecutive cold generations did not further increase size and could even reduce it. These results show that combining cold-selected lines with strategically timed cold rearing can generate larger predators without permanently slowing mass rearing, although prolonged exposure to low temperature may be counterproductive.
The global spread of invasive insects poses serious ecological and economic threats to forest ecosystems. Euwallacea fornicatus and E. perbrevis are cryptic ambrosia beetles native to Southeast Asia that have invaded multiple regions worldwide, damaging diverse woody hosts through gallery formation and fungal symbiont inoculation. We compiled confirmed and novel occurrence records to describe their global distributions, reconstruct invasion histories and likely origins using mitochondrial COI phylogenies, and compare their potential distributions through models based on bioclimatic variables. Euwallacea fornicatus has expanded rapidly over the past decades, establishing in North America (2003), Israel (2009), South Africa (2016), South America (2020), Australia (2021), Europe (2022), and Turkey (2024). In contrast, E. perbrevis has an earlier but slower invasion history, with establishments in Hawaii (1918), Central America (1979), Oceania (1982), and North America (2004). Phylogenetic analyses revealed at least six independent introductions for each species. Euwallacea fornicatus primarily originated from native populations in China, Taiwan, and Vietnam, whereas E. perbrevis from Indonesia and Thailand, with additional introductions from unknown sources. Secondary spread from invaded regions is also likely. Distribution models indicated distinct climatic niches. Euwallacea fornicatus tolerates broader thermal ranges and drier conditions, enabling establishment from subtropical to temperate regions, whereas E. perbrevis appears restricted to tropical climates. Only 32
The oak lace bug (OLB, Corythucha arcuata), originally native to North America, is a rapidly spreading invasive insect in Europe. Since its first detection in Italy in 2000, it has been reported in 25 countries, with its expansion largely driven by human-mediated dispersal. OLB is a multivoltine species, and its spread is further facilitated by the fact that nearly all Eurasian deciduous oak species are potential hosts, and it can also feed on several other woody plants. As a result, OLB has the potential to occupy up to 30 million hectares of oak forests in Europe and even more in Asia. Some studies indicate that OLB has significant negative effects on oaks and associated ecosystems. It reduces photosynthetic activity in oaks, impairs seedling growth, and there are implications that it also decreases fecundity. These impacts weaken tree health and could threaten the diverse communities of herbivores dependent on oaks. OLB may also influence other ecosystem components, such as leaf litter, surface waters, and even human health. Although its population dynamics are influenced by climatic conditions, current evidence suggests that European winters do not strongly constrain its spread. Various chemical control methods and some biological control agents have been tested, but no effective and environmentally sustainable management strategy is currently available. The egg parasitoid Erythmelus klopomor is the only known specialist enemy of OLB in North America and represents a promising long-term control option. However, further research on its behavior and host range is necessary before considering its intentional introduction to Europe.
In-depth research has been conducted on plant–herbivore interactions, and most studies on resistance to insects have been focused on plants post-emergence. Currently, little is known about how seeds respond to pest feeding. Understanding how seeds defend against pests is crucial for seed security and agricultural production. Our study revealed that mild infestation by cowpea weevil (Callosobruchus maculatus), a major pest of stored pulses, activated a defense response in stored cowpea seeds. The infestation eliminated the hardseededness and upregulated the germination-prompted genes, thereby increasing the germination rate. Detailed analysis revealed that infestation induced the expression of a series of defense genes, including those involved in the jasmonic acid (JA) signaling pathway and terpenoid synthetic pathway. Transcriptomic and metabolomic analyses identified flavonoid biosynthesis as the primary response in the infested seeds. Specifically, the isoflavonoid biosynthesis was active, with increased expression of corresponding genes and accumulation of metabolites. Further Y-tube olfactometer selection experiments showed that the infested cowpea seeds attracted male insects but repelled females, indicating that pest feeding altered the volatiles emitted by cowpeas. Our findings thus elucidated the interaction between cowpea seeds and the storage pest and indicated that seeds and plants employ similar defense systems against pests. The study also provides theoretical guidance for controlling C. maculatus.
Plant-herbivore-predator interactions shape community structure and ecosystem services (e.g., biocontrol). Herbivores often prefer the lower leaf side to avoid predators and environmental stress, but the mechanisms remain unclear due to confounding factors such as leaf orientation (upper vs. lower side) and surface structure (abaxial vs. adaxial surface). Here, we examined (1) herbivore preference for leaf orientation and surface structure (herbivory preference experiment), (2) its effect on predator–prey interactions (predation efficiency experiment), and (3) how leaf-mediated predation affects herbivore population dynamics and biocontrol (population growth modeling experiment). Using a soybean system consisting of soybean (Glycine max), soybean aphid (Aphis glycines), and six-spotted zigzag ladybeetle (Cheilomenes sexmaculata), we separated the effects of leaf orientation and surface structure with artificial leaves. We also experimentally reduced trichome density to evaluate its effect on predation rates and incorporated empirical data into population models. The results showed: (1) Aphid preference was primarily driven by leaf surface microstructure, particularly trichome density, rather than leaf orientation, with aphids favoring abaxial over adaxial surfaces (65.3
The eri silkworm, Samia ricini, is the world’s third most important silkworm species, valued for its cocoon silk in traditional textiles as well as its diverse by-products, including edible pupae, bioactive materials, and organic fertilizers. Its large eggs also provide a promising factitious host for the mass-rearing of Trichogramma egg parasitoids in biological control programs. This study aimed to determine (i) whether host plants influence the development of S. ricini and (ii) whether such host plant effects cascade to the performance of six Trichogramma species. Larvae were reared on castor (Ricinus communis), Nepalese coriaria (Coriaria nepalensis), or cassava (Manihot esculenta), and key life history traits were assessed across the entire life cycle, including larval growth, developmental time, cocoon/pupal weights, adult longevity, and egg characteristics. Silkworms reared on castor showed faster larval development, higher body weight, greater cocoon/pupal mass, and longer adult longevity. Eggs from castor-fed silkworms were significantly wider, though eggshell thickness did not differ among host plants. Parallelly, the suitability of S. ricini eggs from each host plant was evaluated for Trichogramma parasitism rate, emergence rate, offspring sex ratio, and developmental time. For most Trichogramma species, eggs from castor- or cassava-fed silkworms resulted in higher parasitism and emergence rates than those from Nepalese coriaria-fed hosts. However, parasitoid responses also showed clear species-specific patterns. The developmental time of several Trichogramma species was prolonged on castor-fed silkworm eggs, indicating a trade-off between developmental time and resource acquisition. Host plant identity strongly mediated tri-trophic interactions by shaping S. ricini performance and egg suitability for parasitoids.
Microorganisms residing in the insect gut play important roles in host nutrition, digestion, detoxification, and resistance to pathogens. However, the functions of gut microbial Volatile Organic Compounds (mVOCs) from insects remain largely unexplored. The oriental fruit moth, Grapholita molesta (Lepidoptera: Tortricidae), is recognized as one of the most destructive orchard pests affecting various Rosaceae fruit trees globally. In this study, we researched G. molesta and successfully isolated and identified eight bacterial and fungal strains from different genera present in the midgut of larvae and adults. Our findings indicated that both male and female adults of G. molesta were attracted to the ML10 and LAP strains, as demonstrated by Y-tube olfactometer assays. We subsequently analyzed their volatile compounds using Headspace Gas Chromatography-Ion Mobility Spectrometry (HS-GC-IMS). Y-tube olfactometer assays revealed that 2-methylpropanoic acid and 2-pentanone effectively attracted female adults at a concentration of 10 ppm. Additionally, heptaldehyde attracted female adults at concentrations of 0.1 ppm and 1 ppm. These findings expand the spectrum of volatile compounds that attract G. molesta and provide a foundation for developing microbe-based attractants for controlling this species.
