Jasmonicacid–elicited volatiles in wheat mediate pink stem borer suppression and parasitoid attraction

Jasmonicacid–elicited volatiles in wheat mediate pink stem borer suppression and parasitoid attraction | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Jasmonicacid–elicited volatiles in wheat mediate pink stem borer suppression and parasitoid attraction Rani Malawanthkar, Ramasamy Kanagaraj Murali-Baskaran This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7638087/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Wheat ( Triticum aestivum L.) productivity in South Asia is increasingly constrained by the pink stem borer ( Sesamia inferens ), a lepidopteran pest responsible for severe yield losses. Conventional insecticide use often results in resistance and ecological risks, underscoring the need for environmentally sustainable alternatives. In this study, we evaluated the efficacy of four elicitors—jasmonic acid (JA), salicylic acid (SA), methyl salicylate (MeSA), and chitosan—in enhancing wheat resistance under field conditions across two consecutive winter seasons. Foliar application of JA (5 mM at 35 and 45 days after sowing) significantly reduced ‘dead heart’ and ‘white ear’ incidence by 31.7% and 27.9%, respectively, and increased grain yield by 28.9% compared with untreated controls. Gas chromatography–mass spectrometry revealed that JA application and borer infestation induced complex volatile blends, with hydrocarbons such as octadecane and eicosane strongly enhancing the foraging efficiency of the egg parasitoid Trichogramma chilonis in laboratory assays. These findings highlight the dual role of JA-elicited volatiles in directly suppressing pest damage and indirectly promoting biological control, offering a practical framework for integrating elicitor-based defense activation into wheat integrated pest management (IPM) strategies. Triticum aestivum. Sesamia inferens . jasmonic acid. herbivore-induced plant volatiles. Trichogramma chilonis. sustainable pest management Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Introduction Wheat ( Triticum aestivum L.) is the second most important cereal crop by acreage after rice, and the third in production after rice and maize. In recent years, the pink stem borer ( Sesamia inferens Walker) has emerged as a significant pest of wheat in India, causing characteristic ‘dead heart’ symptoms during tillering and ‘white ear’ symptoms at the reproductive stage, with yield losses estimated at 15–20% (Bhowmik and Rudra 2017 ). Reliance on chemical insecticides remains the primary control strategy; however, repeated and indiscriminate use has accelerated resistance in pest populations, generated ecological risks, and undermined the sustainability of wheat production (Deshmukh et al. 2010 ). These limitations highlight the need for alternative, environmentally benign management approaches (Kumar et al. 2005 ). The use of plant-derived elicitors has recently gained attention as a promising strategy to strengthen crop resistance against biotic and abiotic stressors (Cofer et al. 2018 ). Elicitors activate inducible defense pathways, including the production of herbivore-induced plant volatiles (HIPVs), which mediate both direct resistance against herbivores and indirect resistance through natural enemy attraction. Synthetic elicitors, though structurally distinct from endogenous phytohormones, can trigger immune-like responses via receptor-mediated signaling, leading to enhanced biosynthesis of secondary metabolites and phytoalexins (Gowthami 2018 ). Evidence for the effectiveness of elicitors has been reported across multiple crop–pest systems: suppression of the brown planthopper in rice (Senthil-Nathan et al. 2009), reduced injury by the rice leaffolder ( Cnaphalocrocis medinalis ) (Kalaivani et al. 2018 ), improved resistance to wheat aphid ( Sitobion avenae ) (Cao et al. 2014 ), protection against Helicoverpa armigera in groundnut (War et al. 2015), reduced feeding by fall armyworm in cotton and soybean (Gordy et al., 2015 ), deterrence of tomato whitefly ( Bemisia tabaci ) (Shi et al. 2013), and resistance to Spodoptera exigua , diamondback moth ( Plutella xylostella ), green peach aphid ( Myzus persicae ), and Manduca sexta (Thaler et al. 2001; Haas and Bostock 2018 ; Redman et al. 2001). Indirect defenses mediated by HIPVs are particularly important for enhancing the efficacy of egg parasitoids such as Trichogramma spp., which are widely recognized for regulating lepidopteran pests in cereals and other crops (Smith 1996; Hassan 1993 ; Li 1994 ; Romeis et al. 1999). Their foraging behavior is strongly influenced by HIPVs and synthetic hydrocarbons, which improve host-location efficiency (Fatouros et al. 2008 ; Parthiban et al. 2016; Pawar et al. 2023). Combining elicitor-induced volatile signaling with Trichogramma deployment therefore represents a synergistic approach to integrated pest management (Murali-Baskaran et al. 2021 ; Xiao et al. 2022). Based on this background, the present study was designed to evaluate the field efficacy of four elicitors—jasmonic acid (JA), salicylic acid (SA), methyl salicylate (MeSA), and chitosan—against S. inferens in wheat, and to characterize the volatile organic compound (VOC) profiles induced by herbivory and elicitor treatment. Further, key VOCs were functionally tested for their role in modulating the foraging activity of Trichogramma chilonis . By integrating applied field data with mechanistic insights into volatile-mediated tritrophic interactions, this work explores the potential of elicitor-based strategies for sustainable wheat protection. Materials and methods Preparation of plant-derived synthetic elicitors Four synthetic elicitors—jasmonic acid (JA), salicylic acid (SA), methyl salicylate (MeSA), and chitosan—were obtained from Hi-Media India Ltd. Based on earlier evidence of elevated endogenous salicylic acid levels in monocots ( Triticum aestivum ) (Stella de Freitas et al. 2019), SA and MeSA were tested at higher concentrations (8 and 16 mM), while JA and chitosan were evaluated at 2.5 and 5 mM. Salicylic Acid (SA) To formulate 2.5 mM and 5 mM solutions, 0.35 g and 0.69 g of SA, respectively, were initially dissolved in 1 mL of ethyl acetate before being diluted to 1 L with distilled water. For higher concentrations (8 mM and 16 mM), 1.10 g and 2.21 g of SA were used, respectively, following the same procedure. Methyl Salicylate (MeSA) For MeSA preparations, 0.38 g and 0.76 g were dissolved in 1 mL of ethanol and subsequently diluted with distilled water to make 1 L solutions of 2.5 mM and 5 mM. Similarly, 1.22 g and 2.43 g of MeSA were used to prepare 8 mM and 16 mM solutions, respectively. Jasmonic Acid (JA) To obtain the desired concentrations of 2.5 mM and 5 mM, 0.53 g and 1.05 g of JA were separately dissolved in 1 mL of ethanol and then diluted to 1 L using distilled water. Chitosan To prepare 2.5 mM and 5 mM chitosan solutions, 3.82 g and 7.64 g of chitosan were each solubilized in 1 mL of 1% acetic acid and pre-dissolved in 100 mL of distilled water. The mixtures were agitated on an orbital shaker at 200 rpm for 4 hours at 28°C, and the final volumes were adjusted to 1 L with distilled water. Field Experiments Evaluation of foliar application of elicitors for management of wheat pink stem borer during winter 2021–22 and 2022–23 Two independent field trials were conducted during the winter seasons of 2021–22 and 2022–23 using the wheat cultivar GW 273. A two-factorial randomized block design (RBD) was adopted to evaluate the efficacy of foliar-applied plant elicitors against the pink stem borer ( Sesamia inferens ). The experimental treatments were as follows: T1, salicylic acid (8 mM); T2, salicylic acid (16 mM); T3, methyl salicylate (8 mM); T4, methyl salicylate (16 mM); T5, jasmonic acid (2.5 mM); T6, jasmonic acid (5 mM); T7, chitosan (2.5 mM); T8, chitosan (5 mM); and T9, untreated control. In this study, four elicitors—jasmonic acid (JA), salicylic acid (SA), methyl salicylate (MeSA), and chitosan—were selected for their reported roles in plant defense. JA is a key signaling molecule in herbivore-induced resistance, regulating volatile emission and secondary metabolite biosynthesis (Karban and Chen 2007; El-Wakeil et al. 2010). SA is primarily associated with pathogen defense, but elevated endogenous SA levels in monocots, including wheat, suggest a broader role in cross-kingdom resistance (Stella de Freitas et al. 2019). MeSA, a volatile derivative of SA, is involved in systemic acquired resistance and influences interactions with both herbivores and natural enemies (Zhu and Park 2005; Ninkovic et al. 2021). Chitosan, a natural biopolymer derived from chitin, acts as a pathogen-associated molecular pattern (PAMP) elicitor, inducing phytoalexin production and cell wall strengthening, although its effectiveness against insect pests has been less widely reported (Li et al. 2016). Collectively, these elicitors represent distinct defense pathways that may be exploited to suppress insect pests while reducing reliance on chemical insecticides. Each treatment was replicated three times with individual plot sizes of 12 m². A buffer distance of 1 m between adjacent plots and 3 m between replications was maintained to minimize drift contamination. Foliar applications were carried out twice, at 35 and 45 days after sowing (DAS), using a one-liter, manually operated hand sprayer (100 mL per plot). Untreated plots served as controls, and no chemical pest control measures were applied during the trial. Pest incidence was assessed visually using standard entomological criteria. The incidence of “dead heart” (caused by larval tunneling during the vegetative phase) was recorded at 42, 49, 56, and 63 DAS, while the incidence of “white ear” (sterile or poorly filled spikes during the reproductive phase) was recorded at 73, 83, and 93 DAS. Symptom incidence was calculated as follows: Laboratory Experiments Profiling of herbivore- and JA-induced volatile organic compounds (VOCs) in wheat To characterize volatile organic compounds (VOCs) emitted by wheat in response to biotic and chemical elicitation, three seeds were sown per plastic pot (15 cm diameter × 15 cm height) and maintained under controlled conditions until seedlings reached 20–25 days of age. At this stage, plants were either infested with second-instar larvae of Sesamia inferens or treated exogenously with jasmonic acid (JA, 5 mM). Plants were left undisturbed for 12–15 h after infestation or treatment prior to volatile collection. JA was applied with a hand-held pressurized sprayer until runoff to ensure uniform coverage. Larvae of S. inferens were introduced 12–15 h after JA treatment, as previous studies have shown that jasmonate-induced volatile emission and defense gene activation peak within 12–24 h of elicitation (El-Wakeil et al. 2010; Aslam et al. 2022). For insect treatments, one larva was released per seedling. Treated plants were then maintained under undisturbed conditions for 12–15 h before volatile collection. Emissions were captured using a dynamic headspace trapping system fitted with TENAX-GR (20/35 mesh) adsorbent for 5 h. Following collection, the adsorbent was transferred to 50 mL conical flasks containing 10 mL of HPLC-grade ethyl acetate. VOCs were extracted by agitation in an orbital incubator shaker (28 °C; 150 rpm) for 1 h, and the solvent was subsequently filtered to remove the adsorbent matrix. Extracts were analyzed by gas chromatography–mass spectrometry (GC–MS; Agilent Technologies) for qualitative and quantitative profiling. TENAX-GR was selected for its high thermal stability and efficiency in trapping medium- to long-chain hydrocarbons and fatty acid derivatives (C6–C30), which were the main target volatiles in this study. Although TENAX is commonly used for thermal desorption, solvent elution with ethyl acetate has been validated in comparable chemical ecology studies (Holopainen et al. 2009; Xiao et al. 2022). Evaluation of key synthetic volatiles on the foraging behavior of T.chilonis To screen VOCs that enhance host-seeking by the egg parasitoid T. chilonis , one-day-old sentinel eggs of Corcyra cephalonica were obtained from the Chemical Ecology Laboratory, ICAR-NIBSM, Raipur, and surface-sterilized before use. Adult T. chilonis used in the assays were newly emerged (<24 h), mated females reared on UV-sterilized C. cephalonica eggs under laboratory conditions (23 ± 2 °C, 65 ± 5% RH, 12:12 h L:D photoperiod). Only females were used because they perform oviposition. Wasps were provided with a 10% honey solution ad libitum and kept naïve (without prior oviposition experience or exposure to host cues) to eliminate conditioning bias. C. cephalonica eggs were chosen as a factitious host because they are larger, readily available in bulk, easy to sterilize and standardize (UV treatment), and permit consistent replication in laboratory bioassays. By contrast, eggs of S. inferens are difficult to obtain in sufficient numbers and are seasonally restricted. Use of C. cephalonica eggs thus ensured experimental uniformity while still allowing assessment of VOC effects on T. chilonis foraging, consistent with established chemical-ecology protocols. Egg batches were treated with 10 mL HPLC-grade hexane in an incubator shaker (28°C, 200 rpm) for 15 min to remove endogenous kairomonal residues. Excess solvent was removed by rinsing with distilled water. Washed eggs were affixed onto cardboard strips (7 × 2 cm; 80–100 eggs per strip) and rendered non-viable by UV irradiation for 20 min. Synthetic analogues of four VOCs identified from JA- and herbivore-induced VOC profiles (octadecane, 1-nonadecene, eicosane, and n-hexadecanoic acid) were dissolved in HPLC-grade hexane at 200 and 500 ppm. These concentrations were selected (i) to approximate ecologically relevant, field-comparable amounts inferred from GC–MS relative abundances, (ii) to conform with concentration ranges used in prior parasitoid bioassays, and (iii) to permit detection of dose-dependent attraction or repellence. The 200-ppm dose served as the principal assay concentration based on preliminary screening and previous studies showing consistent attraction; the 500-ppm level was included to test for possible saturation or repellence (Parthiban et al. 2016; Xiao et al. 2022; Pawar et al. 2023). All compounds were applied in HPLC-grade hexane; solvent controls were included to account for carrier effects. Solvent-washed eggs served as negative controls, whereas untreated eggs retaining natural kairomones served as positive controls. Treated egg cards were exposed to the respective synthetic VOCs for 30s, air-dried in the shade, and used in choice assays to assess T. chilonis preference (Pawar et al. 2023). Each treatment was replicated six times. Egg cards (treated, negative control, and untreated) were symmetrically arranged inside a circular plastic bioassay chamber (8.5 cm diameter × 5 cm height). Cards bearing parasitized eggs were placed at the centre of the arena at a parasitized: unparasitized ratio of 1:6. After 24 h exposure, egg cards were transferred individually to glass tubes (7.5 × 2.5 cm) and incubated at 23 °C and 65% RH. Percentage parasitism was recorded on days 3, 5 and 7 post-inoculation by counting total and parasitized (darkened) eggs under a stereomicroscope. Statistical Analysis Field experiments were analyzed using a two-factorial randomized block design (RBD) with three replications per treatment across two growing seasons (2021–22 and 2022–23). Treatments (elicitor sprays) and observation periods (42–63 DAS for dead heart incidence; 73–90 DAS for white ear incidence) were considered fixed factors, while season was treated as a random factor. Data on pest incidence (% dead heart and % white ear) and parasitism rates were subjected to arcsine transformation, and wheat yield data were log-transformed to satisfy assumptions of normality and homogeneity of variance. Laboratory behavioral assays were analyzed using one-way ANOVA with treatment (volatile compound) as the fixed factor. Each treatment consisted of six independent replicates (egg cards). Percentage parasitism was recorded at 3, 5, and 7 days after inoculation (DAI). In all cases, treatment means were separated using Tukey’s Honest Significant Difference (HSD) test at α = 0.05. Date on relative abundance are presented as mean ± standard error (SE). All statistical analyses were performed using WINKS SDA software (Version 7.0; Texasoft, Cedar Hill, Texas, USA). Results Field Experiments Assessment of foliar application of synthetic plant elicitors for the management of pink Stem borer in wheat during the winter seasons of 2021–22 and 2022–23 The efficacy of four synthetic plant elicitors was assessed under field conditions during two consecutive winter seasons (2021–22 and 2022–23) at two concentration levels. The primary objective was to evaluate their impact on Scirpophaga inferens infestation and subsequent effects on wheat grain yield. Foliar application of jasmonic acid (JA, 5 mM), applied twice at 35 and 45 DAS, consistently suppressed pest-induced symptoms, including dead heart and white ear, with no significant seasonal variation across treatments. Natural infestations of S. inferens were present in both seasons, ensuring uniform pest pressure. In the untreated control plots, mean dead heart incidence was 5.38% in 2021–22 and 5.56% in 2022–23, while white ear incidence was 7.61% and 8.50%, respectively (Fig. 1; Table S1). These values confirm that natural pest pressure was adequate and comparable across replications, providing a reliable baseline for treatment evaluation. Randomized field design minimized positional bias, and no artificial infestation was introduced. Weather data from the ICAR-NIBSM meteorological observatory indicated similar growing conditions across the two seasons, with mean daily temperatures ranging from 18–26°C (2021–22) and 17–27°C (2022–23), and seasonal rainfall differing by <8%, consistent with typical regional winter wheat environments. Among the elicitors tested, JA 5 mM was consistently the most effective , recording the lowest mean dead heart incidence (3.71%), corresponding to a 31.68% reduction compared with the control ( F 8,35 = 46.12; P<0.000). This was followed by JA 2.5 mM (4.05%, 25.41% reduction). Both SA treatments also provided significant suppression, with 16 mM (4.26%, 21.55% reduction) outperforming 8 mM (4.39%, 19.15% reduction). MeSA treatments were slightly less effective, reducing dead heart incidence by 18.23% (16 mM, 4.44%) and 15.65% (8 mM, 4.58%). In contrast, chitosan provided only limited protection, with reductions of 9.02% (5 mM, 4.94%) and 8.66% (2.5 mM, 4.96%). Overall, JA at 5 mM emerged as the most potent elicitor, followed by SA and MeSA, while chitosan demonstrated only marginal suppression (Fig. 1; Supplement table 1 ). A day-wise analysis further confirmed these trends. At 42 DAS , JA 5 mM (3.60%) showed the strongest reduction in dead heart ( F 8,62 = 3.13; P<0.025), closely followed by JA 2.5 mM (3.88%). SA and MeSA treatments recorded intermediate levels (4.35–4.84%), while chitosan was least effective (4.85–4.99%). At 49 DAS , JA 5 mM (4.02%) maintained its superiority ( F 8,62 = 3.42; P<0.017), with JA 2.5 mM (4.26%) again performing next best. SA (4.33–4.53%) and MeSA (4.57–4.72%) significantly reduced dead heart compared with control (5.56%), while chitosan treatments (5.00–5.09%) showed only marginal improvements. At 56 DAS , the control plots reached the highest incidence (5.95%), but JA 5 mM (3.98%) continued to offer the greatest protection ( F 8,62 = 3.40; P<0.018), followed by JA 2.5 mM (4.33%). SA and MeSA (4.70–4.86%) provided moderate suppression, while chitosan remained least effective (5.35–5.39%). Finally, at 63 DAS , the lowest incidence was again recorded in JA 5 mM plots (3.20%) ( F 8,62 = 2.57; P<0.052), followed by JA 2.5 mM (3.71%). SA (3.48–3.97%) and MeSA (3.67–3.98%) offered moderate reductions, whereas chitosan (4.39–4.51%) showed minimal improvement over control (4.84%) (Fig. 2; Supplement table 1 ). Among all treatments, JA 5 mM proved most effective, recording the lowest mean white ear incidence ( 5.49% ) ( F 8,26 = 65.00; P<0.000), which represented a 27.86% reduction compared with the untreated control. This was followed by JA 2.5 mM with an incidence of 5.85% and a 23.13% reduction . Both concentrations of SA also significantly reduced white ear incidence, with 16 mM (5.80%, 23.78% reduction) performing slightly better than 8 mM (6.08%, 20.11% reduction) . Similarly, methyl salicylate (MeSA) treatments reduced incidence by 20.76% at 16 mM (6.03%) and 17.61% at 8 mM (6.27%) . In contrast, chitosan treatments were least effective, with mean incidences of 6.84–6.86% , corresponding to only 9.86–10.12% reduction over the control (Fig. 3; Supplement table S2 ). A day-wise analysis confirmed these trends. At 73 DAS , the lowest incidence was observed in JA 5 mM (3.64%) , corresponding to a 32.73% reduction ( F 8,45 = 3.01; P<0.029). JA 2.5 mM (3.75%, 30.68% reduction) and SA 16 mM (3.86%, 28.64% reduction) were also highly effective. MeSA 16 mM (4.02%) and SA 8 mM (3.96%) provided notable suppression (25.69% and 26.80% reductions, respectively). By contrast, chitosan treatments (4.86–4.95%) yielded only modest reductions (9.28–10.17%).At 83 DAS , the control plots recorded the highest incidence ( 8.50% ). Once again, JA 5 mM (6.23%) provided maximum protection, achieving a 26.82% reduction ( F 8,45 = 8.03; P<0.000). SA 16 mM (6.44%, 24.24% reduction) and JA 2.5 mM (6.56%, 22.82% reduction) followed. Moderate reductions were observed with SA 8 mM (6.81%, 19.88% reduction) , MeSA 16 mM (6.83%, 20.00% reduction) , and MeSA 8 mM (6.95%, 18.24% reduction) . Chitosan (7.52–7.61%) was again least effective, reducing incidence by only 10.35–11.53%.At 90 DAS , the control reached its peak incidence ( 8.93% ). The strongest suppression was recorded with JA 5 mM (6.60%) , corresponding to a 26.09% reduction ( F 8,45 = 6.65; P<0.000). This was followed by SA 16 mM (7.10%, 20.60% reduction) and JA 2.5 mM (7.24%, 18.90% reduction) . Intermediate reductions were noted in MeSA 16 mM (7.23%, 19.05%) , MeSA 8 mM (7.25%, 18.81%) , and SA 8 mM (7.48%, 16.85%) . The lowest effectiveness was observed in chitosan (8.06–8.10%) , which reduced incidence by only 9.30–9.75% compared with control (Fig. 4; Supplement table 2 ). Grain yield reflected the extent of pest suppression. The highest yield was obtained with JA 5 mM (4763.75 kg ha⁻¹) , representing a 28.87% increase over control ( F 8,26 = 1,294,592.83; P<0.000). This was followed by JA 2.5 mM (3872.22 kg ha⁻¹, 12.49% increase) and SA 16 mM (3877.78 kg ha⁻¹, 12.62% increase) . Moderate gains were achieved with MeSA 16 mM (3851.89 kg ha⁻¹, 12.03%) , SA 8 mM (3687.33 kg ha⁻¹, 8.10%) , and MeSA 8 mM (3648.72 kg ha⁻¹,7.13%) . The least improvement was observed with chitosan (3561.11–3605.56 kg ha⁻¹) , corresponding to only 4.85–6.02% increase over the control (Fig. 3; Supplement table 2 ). Laboratory experiments Comparative analysis of volatile profiles in pink stem borer–infested, JA-treated, and untreated wheat seedlings Healthy wheat seedlings emitted a relatively simple volatile blend comprising twelve compounds, whereas pink stem borer (PSB) infestation expanded the profile to twenty-two compounds, and exogenous JA application induced the most diverse response with twenty-eight compounds. In healthy seedlings, the volatile spectrum was dominated by nitrogenous and aromatic compounds such as 3,5-dimethyl-pyrazol-1-yl-[1,2,5]oxadiazolo (40.08 ± 0.50% area) and 4-(4,7-dimethoxy-2H-1,3-benzodioxol-5-yl)-1,3-dimethyl-4H,5H,7H-pyrazolo[3,4-b]pyridin-6-one (16.75±0.44%). Several mid-polar volatiles including cis-1-chloro-9-octadecene (11.73±0.44%) and benzenedicarboxylic acid bis(2-methylpropyl) ester (9.07±0.63%) were also abundant. Hydrocarbons such as 1-hexen-4-yne and octadecane,5-methyl- occurred only in trace amounts (<3%) ( Supplement table 3 ). Upon PSB infestation, the chemical profile shifted towards fatty acids and esters. Oxirane, hexadecyl- (11.0±0.44%), 2-butenedioic acid monododecyl ester (8.28±0.50%), and 4-nitro-5,6,7,8-tetrahydronaphthalen-1-ol (7.85±0.44%) became the most abundant volatiles. The hydrocarbon fraction was enriched with 1-nonadecene (5.50±0.50%) and tetracosane (3.37±0.44%). Notably, several nitrogen- and oxygen-rich compounds present in healthy seedlings (e.g., pyrazolyloxadiazole and benzodioxol derivatives) were absent under infestation, indicating a qualitative reconfiguration of the volatile blend ( Supplement table S3 ). JA elicitation further diversified the bouquet, eliciting unique volatiles absent in both healthy and infested plants. Nonadecylheptafluorobutyrate (7.83±0.63%), oxirane, hexadecyl- (9.80 ± 0.50%), and tetracosane (4.69±0.50%) were highly abundant, alongside strong emissions of benzenedicarboxylic acid bis(2-methylpropyl) ester (11.11±0.44%) and eicosanoic acid methyl ester (5.99±0.44%). Hydrocarbon emissions were more pronounced under JA, with octadecane,5-methyl- reaching 4.21±0.50% compared to <1% in controls. Importantly, 5,5-diethylpentadecane was uniquely induced by JA, highlighting elicitor-specific metabolic activation ( Supplement table S3 ). Retention time comparisons revealed that certain compounds appeared at multiple peaks, likely reflecting branched-chain isomers or structural analogues (e.g., methylated derivatives of tetracosane). Although the mass spectra were similar, subtle structural differences caused elution at distinct retention times. Overall, the transition from healthy to infested to JA-treated plants reflects a progression from nitrogenous/aromatic dominance to ester- and hydrocarbon-enriched blends. JA elicitation not only amplified the relative abundance of several PSB-induced compounds but also induced novel volatiles, resulting in the most complex and diverse VOC profile. Identification of promising plant volatiles enhancing foraging behavior of T. chilonis via choice assay Four synthetic plant volatiles, predominantly identified in volatile profiles induced by pink stem borer (PSB) infestation and JA treatment in wheat seedlings, were selected for laboratory evaluation. These compounds were consistently abundant in the GC–MS profiles and have been reported in the literature as ecologically active hydrocarbons or fatty acids influencing parasitoid and predator behavior. Their selection was therefore guided by both quantitative abundance and functional relevance, making them biologically meaningful candidates for assessing effects on the foraging behavior of T. chilonis . Choice assays were conducted to determine the influence of these volatiles on parasitoid host-searching relative to hexane-washed Corcyra eggs (devoid of natural kairomones) and untreated eggs retaining natural cues. Among the compounds tested, eicosane (200 ppm) elicited the strongest attraction, with a parasitization rate of 91.8% ( F₅,₁₇ = 7253.69; P<0.000) seven days after parasitoid release, despite the absence of natural kairomones. This response was closely followed by octadecane (90.4%) and n-hexadecanoic acid (89.4%) , both comparable to untreated Corcyra eggs naturally emitting kairomones (90.2%). By contrast, hexane-washed eggs without volatile application exhibited a significantly lower parasitization rate of 25.3% at the same time point (Fig. 5; Supplement table 4 ). The four selected volatiles were re-tested at 500 ppm to examine concentration-dependent effects on the foraging efficiency of T. chilonis . At this higher dose, the greatest parasitization (94.5%) was recorded on unwashed C. cephalonica eggs seven days after parasitoid release. Parasitization on eggs treated with octadecane (92.5%) and n-hexadecanoic acid (90.4%) was statistically similar to that on unwashed eggs, whereas eicosane induced a high but comparatively lower parasitization rate ( 82.5% ). By contrast, hexane-washed eggs lacking natural kairomones supported only 28.1% parasitization at day seven (Fig. 6; Supplement table S5 ). Discussion The escalating limitations of synthetic pesticides, including resistance development and ecological risks, have intensified the search for sustainable crop protection alternatives (Pawar et al. 2023). In this study, foliar application of jasmonic acid (JA) provided consistent protection against the pink stem borer ( Sesamia inferens ) across two growing seasons, significantly reducing both ‘dead heart’ and ‘white ear’ symptoms while enhancing grain yield. These findings demonstrate that elicitor-mediated activation of plant defenses can deliver agronomically meaningful outcomes under field conditions. Notably, JA at 5 mM reduced pest incidence by more than 30% and increased yield by nearly 29%, outperforming other elicitors tested. This result aligns with earlier reports of JA-induced resistance against Haplothrips tritici and Sitodiplosis mosellana in wheat (El-Wakeil et al. 2010 ), and resistance to Sitobion avenae (Cao et al. 2014 ), confirming the broad utility of jasmonates in cereal protection. The present results also highlight the relevance of salicylic acid (SA) and methyl salicylate (MeSA), both of which reduced stem borer symptoms at higher concentrations. The requirement for elevated doses is consistent with the naturally high endogenous salicylate levels in cereals, which can dampen responsiveness to lower external applications (Stella de Freitas et al., 2019). Our findings align with observations of MeSA-induced resistance in barley against Rhopalosiphum padi (Ninkovic et al. 2021) and in rice against stink bugs (Stella de Freitas et al. 2019). Conversely, chitosan treatments were relatively ineffective, corroborating earlier evidence that chitosan is more effective against pathogens than insect pests (Li et al., 2016 ). Volatile profiling revealed that both JA application and pink stem borer infestation induced complex blends of volatile organic compounds (VOCs), with several hydrocarbons in common. JA-treated plants emitted the most diverse profile, including octadecane, eicosane, and n-hexadecanoic acid, which were also abundant in herbivore-induced blends. This mirrors earlier findings where jasmonates or MeSA treatments triggered VOC emissions in wheat, altering the behavior of herbivores and parasitoids (Xiao et al. 2022). Similar elicitor-mediated induction of volatiles has been reported in maize (Cofer et al. 2018 ), barley (Ninkovic et al. 2021), tomato (Kawazu et al. 2012 ), and other systems (Thaler et al. 2001; Gordy et al. 2015 ). Although some studies have cautioned that defense induction may incur yield penalties due to metabolic costs (Redman et al. 2001; Kawazu et al. 2012 ), our results suggest that in wheat, JA-mediated defense can be achieved without compromising productivity. The ecological relevance of JA-induced volatiles was confirmed through behavioral assays with Trichogramma chilonis . Eicosane and octadecane significantly enhanced parasitoid foraging, achieving parasitism levels comparable to eggs with natural kairomones. This is consistent with reports of hydrocarbons such as tricosane, docosane, and tetratriacontane serving as kairomones for Trichogramma spp. (Srivastava et al. 2008; Parthiban et al. 2016). Similar kairomonal activity of herbivore-induced volatiles has been documented in chickpea (Romeis et al. 1999), rice (Murali-Baskaran et al. 2020 , 2021 ), and chilli (Vijaya et al. 2018). The dose-dependent effects observed in our assays, where higher concentrations occasionally reduced attraction, agree with earlier observations that parasitoid responses to hydrocarbons are concentration sensitive (Paul et al. 2008; Parthiban et al. 2016). Together, these findings reinforce the concept that elicitor-mediated volatile induction not only suppresses herbivores directly but also enhances the efficiency of biological control agents. Such dual roles make elicitors promising candidates for integration into pest management programs. Previous studies have highlighted the potential of exogenous chemical elicitors in disease and insect pest management (Holopainen et al. 2009 ; Haas and Bostock 2018 ; War et al. 2015), and our work extends this by demonstrating field-level efficacy against a major wheat pest. By linking crop protection outcomes with mechanistic insights into volatile-mediated tritrophic interactions, this study provides an applied framework for incorporating elicitor sprays into wheat Integrated Pest Management (IPM). Conclusions The detrimental consequences associated with the indiscriminate use of synthetic chemical pesticides have catalyzed a paradigm shift towards environmentally sustainable pest management strategies. Among these, the application of synthetic plant volatiles has shown promising efficacy, particularly in the realm of plant-pathogen interactions. In recent years, there has been a notable surge in research exploring the potential of synthetic elicitors for crop protection. In the present investigation, foliar application of jasmonic acid (JA) at 5 mM concentration, administered twice on the 35th and 45th days post-sowing, significantly mitigated damage symptoms inflicted by the pink stem borer ( Sesamia inferens ), while concomitantly enhancing grain yield. Moreover, exogenous application of JA elicited volatile emissions in wheat seedlings analogous to those induced by pink stem borer infestation. Among the four predominant volatiles identified, eicosane and octadecane notably stimulated the foraging activity of the egg parasitoid T . chilonis , comparable to the attraction elicited by natural kairomones from untreated host eggs. These findings underscore the potential of jasmonic acid as a viable ecological alternative to conventional insecticides, offering a dual advantage of suppressing S. inferens infestation and augmenting the biological control efficacy through parasitoid attraction. Foliar-applied JA thus emerges as a promising tool in the integrated pest management (IPM) framework for sustainable wheat cultivation. Declarations Acknowledgements Student and advisory committee are thankful to the Indian Council of Agricultural Research, DARE, New Delhi and the ICAR-National Institute of Biotic Stress Management, Raipur for financial support and other logistics for conducting the present research both under field and laboratory conditions. Funding Authors are grateful to the Indian Council of Agricultural Research (ICAR), DARE, New Delhi which has provided funds for conducting field experiments. This is contribution of ICAR-NIBSM/Rp-49/2023-06. Author contributions RKMB: Conceptualization and identification of research problem, development of methodology, writing of paper, review; MR: Conduct of field and lab experiments, collection and curing of field and lab data. Ethical approval and consent to participate This research paper does not report or involve the use of any animal or human data or tissue. Consent to Publish and Participate The authors do not report any individual details, images, or videos in this research paper. Competing interests The authors declare that they have no competing interests. Data availability statement All data used in the manuscript are given in the table file, and main text References Aslam H, Mushtaq S, Maalik S, Bano N, Eed EM, Bibi A, TahirA, Ijaz I, Tanwir S, Khalifa AS (2022) Exploring the effect of jasmonic acid for aphid control for improving the yield of Triticum aestivum varieties. PeerJ 10: e14018. https://doi.org/10.7717/peerj.14018 Bhowmik P, Rudra, BC (2017) Assessment of Infestation by Sesamia inferens on wheat varieties under different tillage conditions. J KrishiVigyan 5(2): 5-7. 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In J Mol Sci 26 (2):621. https://doi.org/10.3390/ijms26020621 Additional Declarations No competing interests reported. Supplementary Files Supplementdata.docx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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Data represent mean values of four replications; Data on dead heart were subject to ANOVA after arcsine transformation; DAS: Days after sowing; mM: Millimolar; SA: Salicylic acid; MeSA: Methyl salicylate; JA: Jasmonic acid. In a column, means followed by same letter(s) are not significantly different by HSD at p\u0026lt;0.05.\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7638087/v1/abea964a2b40ba11d96edc35.jpeg"},{"id":92865238,"identity":"0a9da402-a1a3-475b-b8db-6edc719d3b19","added_by":"auto","created_at":"2025-10-06 12:55:54","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":62809,"visible":true,"origin":"","legend":"\u003cp\u003eIncidence of dead heart symptom (%) caused by pink stem borer in wheat, as influenced by foliar application of elicitors (treatments T1–T9) across two winter seasons (2021–22 \u0026amp; 2022–23) and multiple observation periods (42–63 DAS). Data represent mean values of three replications; Data on dead heart were subject to ANOVA after arcsine transformation; DAS: Days after sowing; mM: Millimolar; SA: Salicylic acid; MeSA: Methyl salicylate; JA: Jasmonic acid. In a column, means followed by same letter(s) are not significantly different by HSD at p\u0026lt;0.05.\u003c/p\u003e","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7638087/v1/6eed575bad8da06707a7530f.jpeg"},{"id":92865241,"identity":"ab5a4388-e5e3-44b2-85d6-79ee85a47d9f","added_by":"auto","created_at":"2025-10-06 12:55:54","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":54282,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eMean white ear\u003c/strong\u003esymptom (%) caused by pink stem borer in wheat and their reduction over control, as influenced by foliar application of elicitors (treatments T1–T9) across two winter seasons (2021–22 \u0026amp; 2022–23) and multiple observation periods (73–90 DAS). Data represent mean values of three replications; Data on dead heart were subject to ANOVA after arcsine transformation; DAS: Days after sowing; mM: Millimolar; SA: Salicylic acid; MeSA: Methyl salicylate; JA: Jasmonic acid. In a column, means followed by same letter(s) are not significantly different by HSD at p\u0026lt;0.05.\u003c/p\u003e","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7638087/v1/e3eccf4b937d2531d1613155.jpeg"},{"id":92865635,"identity":"9dbfa63d-9cf8-45f0-8297-f924edef998c","added_by":"auto","created_at":"2025-10-06 13:03:54","extension":"jpeg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":53099,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eWhite ear\u003c/strong\u003esymptom (%) caused by pink stem borer in wheat as influenced by foliar application of elicitors (treatments T1–T9) across two winter seasons (2021–22 \u0026amp; 2022–23) and multiple observation periods (73–90 DAS). Data represent mean values of three replications; Data on dead heart were subject to ANOVA after arcsine transformation; DAS: Days after sowing; mM: Millimolar; SA: Salicylic acid; MeSA: Methyl salicylate; JA: Jasmonic acid. In a column, means followed by same letter(s) are not significantly different by HSD at p\u0026lt;0.05.\u003c/p\u003e","description":"","filename":"floatimage4.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7638087/v1/648e4f5e911c23b3a2389267.jpeg"},{"id":92865246,"identity":"f75bb882-a0c0-4b06-86ab-0b2b85eb0bfd","added_by":"auto","created_at":"2025-10-06 12:55:54","extension":"jpeg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":45523,"visible":true,"origin":"","legend":"\u003cp\u003ePer cent parasitization of \u003cem\u003eT\u003c/em\u003e. \u003cem\u003echilonis \u003c/em\u003eon eggs of \u003cem\u003eCorcyra\u003c/em\u003e, as influenced by selected hydrocarbons induced by pink stem borer feeding and foliar application of JA at 200 ppm in wheat pot plants; *Mean of six replications; In a column, values followed by the same letter(s) do not differ significantly from each other by HSD at p\u0026lt;0.05; DAI: Days after inoculation\u003c/p\u003e","description":"","filename":"floatimage5.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7638087/v1/0edbdf74c848136f2a03bc54.jpeg"},{"id":92865243,"identity":"584e9ccd-a233-4ea5-9b2f-3b7b6abde233","added_by":"auto","created_at":"2025-10-06 12:55:54","extension":"jpeg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":47195,"visible":true,"origin":"","legend":"\u003cp\u003ePer cent parasitization of \u003cem\u003eT\u003c/em\u003e. \u003cem\u003echilonis \u003c/em\u003eon eggs of \u003cem\u003eCorcyra\u003c/em\u003e, as influenced by selected hydrocarbons induced by pink stem borer feeding and foliar application of JA at 500 ppm in wheat pot plants; *Mean of six replications; In a column, values followed by the same letter(s) do not differ significantly from each other by HSD at p\u0026lt;0.05; DAI: Days after inoculation\u003c/p\u003e","description":"","filename":"floatimage6.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7638087/v1/2e7b292f0dc4a53b725f67db.jpeg"},{"id":93378985,"identity":"2f134ea6-5f71-4727-9883-60043446ce7a","added_by":"auto","created_at":"2025-10-13 08:30:32","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1974027,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7638087/v1/35cfbf35-7502-47c1-be63-bafeddae91db.pdf"},{"id":92865245,"identity":"a8636a95-5d56-43ec-a3ed-8b5c58d559dd","added_by":"auto","created_at":"2025-10-06 12:55:54","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":270380,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementdata.docx","url":"https://assets-eu.researchsquare.com/files/rs-7638087/v1/83db9f1e8e236a9fe0d4f14c.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Jasmonicacid–elicited volatiles in wheat mediate pink stem borer suppression and parasitoid attraction","fulltext":[{"header":"Introduction","content":"\u003cp\u003eWheat (\u003cem\u003eTriticum aestivum\u003c/em\u003e L.) is the second most important cereal crop by acreage after rice, and the third in production after rice and maize. In recent years, the pink stem borer (\u003cem\u003eSesamia inferens\u003c/em\u003e Walker) has emerged as a significant pest of wheat in India, causing characteristic \u0026lsquo;dead heart\u0026rsquo; symptoms during tillering and \u0026lsquo;white ear\u0026rsquo; symptoms at the reproductive stage, with yield losses estimated at 15\u0026ndash;20% (Bhowmik and Rudra \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2017\u003c/span\u003e). Reliance on chemical insecticides remains the primary control strategy; however, repeated and indiscriminate use has accelerated resistance in pest populations, generated ecological risks, and undermined the sustainability of wheat production (Deshmukh et al. \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2010\u003c/span\u003e). These limitations highlight the need for alternative, environmentally benign management approaches (Kumar et al. \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2005\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe use of plant-derived elicitors has recently gained attention as a promising strategy to strengthen crop resistance against biotic and abiotic stressors (Cofer et al. \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). Elicitors activate inducible defense pathways, including the production of herbivore-induced plant volatiles (HIPVs), which mediate both direct resistance against herbivores and indirect resistance through natural enemy attraction. Synthetic elicitors, though structurally distinct from endogenous phytohormones, can trigger immune-like responses via receptor-mediated signaling, leading to enhanced biosynthesis of secondary metabolites and phytoalexins (Gowthami \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2018\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eEvidence for the effectiveness of elicitors has been reported across multiple crop\u0026ndash;pest systems: suppression of the brown planthopper in rice (Senthil-Nathan et al. 2009), reduced injury by the rice leaffolder (\u003cem\u003eCnaphalocrocis medinalis\u003c/em\u003e) (Kalaivani et al. \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2018\u003c/span\u003e), improved resistance to wheat aphid (\u003cem\u003eSitobion avenae\u003c/em\u003e) (Cao et al. \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2014\u003c/span\u003e), protection against \u003cem\u003eHelicoverpa armigera\u003c/em\u003e in groundnut (War et al. 2015), reduced feeding by fall armyworm in cotton and soybean (Gordy et al., \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2015\u003c/span\u003e), deterrence of tomato whitefly (\u003cem\u003eBemisia tabaci\u003c/em\u003e) (Shi et al. 2013), and resistance to \u003cem\u003eSpodoptera exigua\u003c/em\u003e, diamondback moth (\u003cem\u003ePlutella xylostella\u003c/em\u003e), green peach aphid (\u003cem\u003eMyzus persicae\u003c/em\u003e), and \u003cem\u003eManduca sexta\u003c/em\u003e (Thaler et al. 2001; Haas and Bostock \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Redman et al. 2001).\u003c/p\u003e\u003cp\u003eIndirect defenses mediated by HIPVs are particularly important for enhancing the efficacy of egg parasitoids such as \u003cem\u003eTrichogramma\u003c/em\u003e spp., which are widely recognized for regulating lepidopteran pests in cereals and other crops (Smith 1996; Hassan \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e1993\u003c/span\u003e; Li \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e1994\u003c/span\u003e; Romeis et al. 1999). Their foraging behavior is strongly influenced by HIPVs and synthetic hydrocarbons, which improve host-location efficiency (Fatouros et al. \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2008\u003c/span\u003e; Parthiban et al. 2016; Pawar et al. 2023). Combining elicitor-induced volatile signaling with \u003cem\u003eTrichogramma\u003c/em\u003e deployment therefore represents a synergistic approach to integrated pest management (Murali-Baskaran et al. \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Xiao et al. 2022).\u003c/p\u003e\u003cp\u003eBased on this background, the present study was designed to evaluate the field efficacy of four elicitors\u0026mdash;jasmonic acid (JA), salicylic acid (SA), methyl salicylate (MeSA), and chitosan\u0026mdash;against \u003cem\u003eS. inferens\u003c/em\u003e in wheat, and to characterize the volatile organic compound (VOC) profiles induced by herbivory and elicitor treatment. Further, key VOCs were functionally tested for their role in modulating the foraging activity of \u003cem\u003eTrichogramma chilonis\u003c/em\u003e. By integrating applied field data with mechanistic insights into volatile-mediated tritrophic interactions, this work explores the potential of elicitor-based strategies for sustainable wheat protection.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cp\u003e\u003cstrong\u003e\u003cem\u003ePreparation of plant-derived synthetic elicitors\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFour synthetic elicitors\u0026mdash;jasmonic acid (JA), salicylic acid (SA), methyl salicylate (MeSA), and chitosan\u0026mdash;were obtained from Hi-Media India Ltd. Based on earlier evidence of elevated endogenous salicylic acid levels in monocots (\u003cem\u003eTriticum aestivum\u003c/em\u003e) (Stella de Freitas et al. 2019), SA and MeSA were tested at higher concentrations (8 and 16 mM), while JA and chitosan were evaluated at 2.5 and 5 mM.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eSalicylic Acid (SA)\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo formulate 2.5 mM and 5 mM solutions, 0.35 g and 0.69 g of SA, respectively, were initially dissolved in 1 mL of ethyl acetate before being diluted to 1 L with distilled water. For higher concentrations (8 mM and 16 mM), 1.10 g and 2.21 g of SA were used, respectively, following the same procedure.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eMethyl Salicylate (MeSA)\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFor MeSA preparations, 0.38 g and 0.76 g were dissolved in 1 mL of ethanol and subsequently diluted with distilled water to make 1 L solutions of 2.5 mM and 5 mM. Similarly, 1.22 g and 2.43 g of MeSA were used to prepare 8 mM and 16 mM solutions, respectively.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eJasmonic Acid (JA)\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo obtain the desired concentrations of 2.5 mM and 5 mM, 0.53 g and 1.05 g of JA were separately dissolved in 1 mL of ethanol and then diluted to 1 L using distilled water.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eChitosan\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo prepare 2.5 mM and 5 mM chitosan solutions, 3.82 g and 7.64 g of chitosan were each solubilized in 1 mL of 1% acetic acid and pre-dissolved in 100 mL of distilled water. The mixtures were agitated on an orbital shaker at 200 rpm for 4 hours at 28\u0026deg;C, and the final volumes were adjusted to 1 L with distilled water.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eField Experiments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eEvaluation of foliar application of elicitors for management of wheat pink stem borer during winter 2021\u0026ndash;22 and 2022\u0026ndash;23\u003c/em\u003e\u003c/strong\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eTwo independent field trials were conducted during the winter seasons of 2021\u0026ndash;22 and 2022\u0026ndash;23 using the wheat cultivar GW 273. A two-factorial randomized block design (RBD) was adopted to evaluate the efficacy of foliar-applied plant elicitors against the pink stem borer (\u003cem\u003eSesamia inferens\u003c/em\u003e). The experimental treatments were as follows: T1, salicylic acid (8 mM); T2, salicylic acid (16 mM); T3, methyl salicylate (8 mM); T4, methyl salicylate (16 mM); T5, jasmonic acid (2.5 mM); T6, jasmonic acid (5 mM); T7, chitosan (2.5 mM); T8, chitosan (5 mM); and T9, untreated control.\u003c/p\u003e\n\u003cp\u003eIn this study, four elicitors\u0026mdash;jasmonic acid (JA), salicylic acid (SA), methyl salicylate (MeSA), and chitosan\u0026mdash;were selected for their reported roles in plant defense. JA is a key signaling molecule in herbivore-induced resistance, regulating volatile emission and secondary metabolite biosynthesis (Karban and Chen 2007; El-Wakeil et al. 2010). SA is primarily associated with pathogen defense, but elevated endogenous SA levels in monocots, including wheat, suggest a broader role in cross-kingdom resistance (Stella de Freitas et al. 2019). MeSA, a volatile derivative of SA, is involved in systemic acquired resistance and influences interactions with both herbivores and natural enemies (Zhu and Park 2005; Ninkovic et al. 2021). Chitosan, a natural biopolymer derived from chitin, acts as a pathogen-associated molecular pattern (PAMP) elicitor, inducing phytoalexin production and cell wall strengthening, although its effectiveness against insect pests has been less widely reported (Li et al. 2016). Collectively, these elicitors represent distinct defense pathways that may be exploited to suppress insect pests while reducing reliance on chemical insecticides.\u003c/p\u003e\n\u003cp\u003eEach treatment was replicated three times with individual plot sizes of 12 m\u0026sup2;. A buffer distance of 1 m between adjacent plots and 3 m between replications was maintained to minimize drift contamination. Foliar applications were carried out twice, at 35 and 45 days after sowing (DAS), using a one-liter, manually operated hand sprayer (100 mL per plot). Untreated plots served as controls, and no chemical pest control measures were applied during the trial.\u003c/p\u003e\n\u003cp\u003ePest incidence was assessed visually using standard entomological criteria. The incidence of \u0026ldquo;dead heart\u0026rdquo; (caused by larval tunneling during the vegetative phase) was recorded at 42, 49, 56, and 63 DAS, while the incidence of \u0026ldquo;white ear\u0026rdquo; (sterile or poorly filled spikes during the reproductive phase) was recorded at 73, 83, and 93 DAS. Symptom incidence was calculated as follows:\u003c/p\u003e\n\u003cp\u003e\u003cimg src=\"https://myfiles.space/user_files/58895_8739fc6c57c1c19a/58895_custom_files/img1759754958.png\" width=\"640\" height=\"217\"\u003e\u003c/p\u003e\n\u003ch3\u003eLaboratory Experiments\u003c/h3\u003e\n\u003ch4\u003eProfiling of herbivore- and JA-induced volatile organic compounds (VOCs) in wheat\u003c/h4\u003e\n\u003cp\u003eTo characterize volatile organic compounds (VOCs) emitted by wheat in response to biotic and chemical elicitation, three seeds were sown per plastic pot (15 cm diameter \u0026times; 15 cm height) and maintained under controlled conditions until seedlings reached 20\u0026ndash;25 days of age. At this stage, plants were either infested with second-instar larvae of \u003cem\u003eSesamia inferens\u003c/em\u003e or treated exogenously with jasmonic acid (JA, 5 mM). Plants were left undisturbed for 12\u0026ndash;15 h after infestation or treatment prior to volatile collection. JA was applied with a hand-held pressurized sprayer until runoff to ensure uniform coverage. Larvae of \u003cem\u003eS. inferens\u003c/em\u003e were introduced 12\u0026ndash;15 h after JA treatment, as previous studies have shown that jasmonate-induced volatile emission and defense gene activation peak within 12\u0026ndash;24 h of elicitation (El-Wakeil et al. 2010; Aslam et al. 2022).\u003c/p\u003e\n\u003cp\u003eFor insect treatments, one larva was released per seedling. Treated plants were then maintained under undisturbed conditions for 12\u0026ndash;15 h before volatile collection. Emissions were captured using a dynamic headspace trapping system fitted with TENAX-GR (20/35 mesh) adsorbent for 5 h. Following collection, the adsorbent was transferred to 50 mL conical flasks containing 10 mL of HPLC-grade ethyl acetate. VOCs were extracted by agitation in an orbital incubator shaker (28 \u0026deg;C; 150 rpm) for 1 h, and the solvent was subsequently filtered to remove the adsorbent matrix. Extracts were analyzed by gas chromatography\u0026ndash;mass spectrometry (GC\u0026ndash;MS; Agilent Technologies) for qualitative and quantitative profiling.\u003c/p\u003e\n\u003cp\u003eTENAX-GR was selected for its high thermal stability and efficiency in trapping medium- to long-chain hydrocarbons and fatty acid derivatives (C6\u0026ndash;C30), which were the main target volatiles in this study. Although TENAX is commonly used for thermal desorption, solvent elution with ethyl acetate has been validated in comparable chemical ecology studies (Holopainen et al. 2009; Xiao et al. 2022).\u003c/p\u003e\n\u003ch4\u003eEvaluation of key synthetic volatiles on the foraging behavior of\u0026nbsp;\u003cem\u003eT.chilonis\u003c/em\u003e\u003c/h4\u003e\n\u003cp\u003eTo screen VOCs that enhance host-seeking by the egg parasitoid \u003cem\u003eT. chilonis\u003c/em\u003e, one-day-old sentinel eggs of \u003cem\u003eCorcyra cephalonica\u003c/em\u003e were obtained from the Chemical Ecology Laboratory, ICAR-NIBSM, Raipur, and surface-sterilized before use. Adult \u003cem\u003eT. chilonis\u003c/em\u003e used in the assays were newly emerged (\u0026lt;24 h), mated females reared on UV-sterilized \u003cem\u003eC. cephalonica\u003c/em\u003e eggs under laboratory conditions (23 \u0026plusmn; 2 \u0026deg;C, 65 \u0026plusmn; 5% RH, 12:12 h L:D photoperiod). Only females were used because they perform oviposition. Wasps were provided with a 10% honey solution ad libitum and kept na\u0026iuml;ve (without prior oviposition experience or exposure to host cues) to eliminate conditioning bias. \u003cem\u003eC. cephalonica\u003c/em\u003e eggs were chosen as a factitious host because they are larger, readily available in bulk, easy to sterilize and standardize (UV treatment), and permit consistent replication in laboratory bioassays. By contrast, eggs of \u003cem\u003eS. inferens\u003c/em\u003e are difficult to obtain in sufficient numbers and are seasonally restricted. Use of \u003cem\u003eC. cephalonica\u003c/em\u003e eggs thus ensured experimental uniformity while still allowing assessment of VOC effects on \u003cem\u003eT. chilonis\u003c/em\u003e foraging, consistent with established chemical-ecology protocols.\u003c/p\u003e\n\u003cp\u003eEgg batches were treated with 10 mL HPLC-grade hexane in an incubator shaker (28\u0026deg;C, 200 rpm) for 15 min to remove endogenous kairomonal residues. Excess solvent was removed by rinsing with distilled water. Washed eggs were affixed onto cardboard strips (7 \u0026times; 2 cm; 80\u0026ndash;100 eggs per strip) and rendered non-viable by UV irradiation for 20 min. Synthetic analogues of four VOCs identified from JA- and herbivore-induced VOC profiles (octadecane, 1-nonadecene, eicosane, and n-hexadecanoic acid) were dissolved in HPLC-grade hexane at 200 and 500 ppm. These concentrations were selected (i) to approximate ecologically relevant, field-comparable amounts inferred from GC\u0026ndash;MS relative abundances, (ii) to conform with concentration ranges used in prior parasitoid bioassays, and (iii) to permit detection of dose-dependent attraction or repellence. The 200-ppm dose served as the principal assay concentration based on preliminary screening and previous studies showing consistent attraction; the 500-ppm level was included to test for possible saturation or repellence (Parthiban et al. 2016; Xiao et al. 2022; Pawar et al. 2023). All compounds were applied in HPLC-grade hexane; solvent controls were included to account for carrier effects.\u003c/p\u003e\n\u003cp\u003eSolvent-washed eggs served as negative controls, whereas untreated eggs retaining natural kairomones served as positive controls. Treated egg cards were exposed to the respective synthetic VOCs for 30s, air-dried in the shade, and used in choice assays to assess \u003cem\u003eT. chilonis\u003c/em\u003e preference (Pawar et al. 2023). Each treatment was replicated six times. Egg cards (treated, negative control, and untreated) were symmetrically arranged inside a circular plastic bioassay chamber (8.5 cm diameter \u0026times; 5 cm height). Cards bearing parasitized eggs were placed at the centre of the arena at a parasitized: unparasitized ratio of 1:6. After 24 h exposure, egg cards were transferred individually to glass tubes (7.5 \u0026times; 2.5 cm) and incubated at 23 \u0026deg;C and 65% RH. Percentage parasitism was recorded on days 3, 5 and 7 post-inoculation by counting total and parasitized (darkened) eggs under a stereomicroscope.\u003c/p\u003e\n\u003ch3\u003e\u003cem\u003eStatistical Analysis\u003c/em\u003e\u003c/h3\u003e\n\u003cp\u003eField experiments were analyzed using a two-factorial randomized block design (RBD) with three replications per treatment across two growing seasons (2021\u0026ndash;22 and 2022\u0026ndash;23). Treatments (elicitor sprays) and observation periods (42\u0026ndash;63 DAS for dead heart incidence; 73\u0026ndash;90 DAS for white ear incidence) were considered fixed factors, while season was treated as a random factor. Data on pest incidence (% dead heart and % white ear) and parasitism rates were subjected to arcsine transformation, and wheat yield data were log-transformed to satisfy assumptions of normality and homogeneity of variance. Laboratory behavioral assays were analyzed using one-way ANOVA with treatment (volatile compound) as the fixed factor. Each treatment consisted of six independent replicates (egg cards). Percentage parasitism was recorded at 3, 5, and 7 days after inoculation (DAI). In all cases, treatment means were separated using Tukey\u0026rsquo;s Honest Significant Difference (HSD) test at \u0026alpha; = 0.05. Date on relative abundance are presented as mean \u0026plusmn; standard error (SE). All statistical analyses were performed using WINKS SDA software (Version 7.0; Texasoft, Cedar Hill, Texas, USA).\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003e\u003cem\u003eField Experiments\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eAssessment of foliar application of synthetic plant elicitors for the management of pink Stem borer in wheat during the winter seasons of 2021\u0026ndash;22 and 2022\u0026ndash;23\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe efficacy of four synthetic plant elicitors was assessed under field conditions during two consecutive winter seasons (2021\u0026ndash;22 and 2022\u0026ndash;23) at two concentration levels. The primary objective was to evaluate their impact on \u003cem\u003eScirpophaga inferens\u003c/em\u003e infestation and subsequent effects on wheat grain yield. Foliar application of jasmonic acid (JA, 5 mM), applied twice at 35 and 45 DAS, consistently suppressed pest-induced symptoms, including dead heart and white ear, with no significant seasonal variation across treatments.\u003c/p\u003e\n\u003cp\u003eNatural infestations of \u003cem\u003eS. inferens\u003c/em\u003e were present in both seasons, ensuring uniform pest pressure. In the untreated control plots, mean dead heart incidence was 5.38% in 2021\u0026ndash;22 and 5.56% in 2022\u0026ndash;23, while white ear incidence was 7.61% and 8.50%, respectively (Fig. 1; Table S1). These values confirm that natural pest pressure was adequate and comparable across replications, providing a reliable baseline for treatment evaluation. Randomized field design minimized positional bias, and no artificial infestation was introduced. Weather data from the ICAR-NIBSM meteorological observatory indicated similar growing conditions across the two seasons, with mean daily temperatures ranging from 18\u0026ndash;26\u0026deg;C (2021\u0026ndash;22) and 17\u0026ndash;27\u0026deg;C (2022\u0026ndash;23), and seasonal rainfall differing by \u0026lt;8%, consistent with typical regional winter wheat environments.\u003c/p\u003e\n\u003cp\u003eAmong the elicitors tested, \u003cstrong\u003eJA 5 mM was consistently the most effective\u003c/strong\u003e, recording the lowest mean dead heart incidence (3.71%), corresponding to a \u003cstrong\u003e31.68% reduction\u003c/strong\u003e compared with the control (\u003cem\u003eF\u003csub\u003e8,35\u003c/sub\u003e\u003c/em\u003e= 46.12; P\u0026lt;0.000). This was followed by JA 2.5 mM (4.05%, 25.41% reduction). Both \u003cstrong\u003eSA\u003c/strong\u003e treatments also provided significant suppression, with 16 mM (4.26%, 21.55% reduction) outperforming 8 mM (4.39%, 19.15% reduction). \u003cstrong\u003eMeSA\u003c/strong\u003e treatments were slightly less effective, reducing dead heart incidence by 18.23% (16 mM, 4.44%) and 15.65% \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; (8 mM, 4.58%). In contrast, \u003cstrong\u003echitosan\u003c/strong\u003e provided only limited protection, with reductions of 9.02% (5 mM, 4.94%) and 8.66% (2.5 mM, 4.96%). Overall, JA at 5 mM emerged as the most potent elicitor, followed by SA and MeSA, while chitosan demonstrated only marginal suppression (Fig. 1; \u003cstrong\u003eSupplement table 1\u003c/strong\u003e).\u003c/p\u003e\n\u003cp\u003eA day-wise analysis further confirmed these trends. At \u003cstrong\u003e42 DAS\u003c/strong\u003e, JA 5 mM (3.60%) showed the strongest reduction in dead heart (\u003cem\u003eF\u003csub\u003e8,62\u003c/sub\u003e\u003c/em\u003e= 3.13; P\u0026lt;0.025), closely followed by JA 2.5 mM (3.88%). SA and MeSA treatments recorded intermediate levels (4.35\u0026ndash;4.84%), while chitosan was least effective (4.85\u0026ndash;4.99%). At \u003cstrong\u003e49 DAS\u003c/strong\u003e, JA 5 mM (4.02%) maintained its superiority (\u003cem\u003eF\u003csub\u003e8,62\u003c/sub\u003e\u003c/em\u003e= 3.42; P\u0026lt;0.017), with JA 2.5 mM (4.26%) again performing next best. SA (4.33\u0026ndash;4.53%) and MeSA (4.57\u0026ndash;4.72%) significantly reduced dead heart compared with control (5.56%), while chitosan treatments (5.00\u0026ndash;5.09%) showed only marginal improvements. At \u003cstrong\u003e56 DAS\u003c/strong\u003e, the control plots reached the highest incidence (5.95%), but JA 5 mM (3.98%) continued to offer the greatest protection (\u003cem\u003eF\u003csub\u003e8,62\u003c/sub\u003e\u003c/em\u003e= 3.40; P\u0026lt;0.018), followed by JA 2.5 mM (4.33%). SA and MeSA (4.70\u0026ndash;4.86%) provided moderate suppression, while chitosan remained least effective (5.35\u0026ndash;5.39%). Finally, at \u003cstrong\u003e63 DAS\u003c/strong\u003e, the lowest incidence was again recorded in JA 5 mM plots (3.20%) (\u003cem\u003eF\u003csub\u003e8,62\u003c/sub\u003e\u003c/em\u003e= 2.57; P\u0026lt;0.052), followed by JA 2.5 mM (3.71%). SA (3.48\u0026ndash;3.97%) and MeSA (3.67\u0026ndash;3.98%) offered moderate reductions, whereas chitosan (4.39\u0026ndash;4.51%) showed minimal improvement over control (4.84%) (Fig. 2; \u003cstrong\u003eSupplement table 1\u003c/strong\u003e).\u003c/p\u003e\n\u003cp\u003eAmong all treatments, \u003cstrong\u003eJA 5 mM\u003c/strong\u003e proved most effective, recording the lowest mean white ear incidence (\u003cstrong\u003e5.49%\u003c/strong\u003e) (\u003cem\u003eF\u003csub\u003e8,26\u003c/sub\u003e\u003c/em\u003e= 65.00; P\u0026lt;0.000), which represented a \u003cstrong\u003e27.86% reduction\u003c/strong\u003e compared with the untreated control. This was followed by \u003cstrong\u003eJA 2.5 mM\u003c/strong\u003e with an incidence of \u003cstrong\u003e5.85%\u003c/strong\u003e and a \u003cstrong\u003e23.13% reduction\u003c/strong\u003e\u003cstrong\u003e.\u0026nbsp;\u003c/strong\u003eBoth concentrations of \u003cstrong\u003eSA\u0026nbsp;\u003c/strong\u003ealso significantly reduced white ear incidence, with \u003cstrong\u003e16 mM (5.80%, 23.78% reduction)\u003c/strong\u003e performing slightly better than \u003cstrong\u003e8 mM (6.08%, 20.11% reduction)\u003c/strong\u003e. Similarly, \u003cstrong\u003emethyl salicylate (MeSA)\u003c/strong\u003e treatments reduced incidence by \u003cstrong\u003e20.76% at 16 mM (6.03%)\u0026nbsp;\u003c/strong\u003eand \u003cstrong\u003e17.61% at 8 mM (6.27%)\u003c/strong\u003e. In contrast, \u003cstrong\u003echitosan treatments\u003c/strong\u003e were least effective, with mean incidences of \u003cstrong\u003e6.84\u0026ndash;6.86%\u003c/strong\u003e, corresponding to only \u003cstrong\u003e9.86\u0026ndash;10.12% reduction\u003c/strong\u003e over the control (Fig. 3; \u003cstrong\u003eSupplement table S2\u003c/strong\u003e).\u003c/p\u003e\n\u003cp\u003eA day-wise analysis confirmed these trends. At \u003cstrong\u003e73 DAS\u003c/strong\u003e, the lowest incidence was observed in \u003cstrong\u003eJA 5 mM (3.64%)\u003c/strong\u003e, corresponding to a \u003cstrong\u003e32.73% reduction\u003c/strong\u003e (\u003cem\u003eF\u003csub\u003e8,45\u003c/sub\u003e\u003c/em\u003e = 3.01; P\u0026lt;0.029). \u003cstrong\u003eJA 2.5 mM (3.75%, 30.68% reduction)\u003c/strong\u003e and \u003cstrong\u003eSA 16 mM (3.86%, 28.64% reduction)\u003c/strong\u003e were also highly effective. \u003cstrong\u003eMeSA 16 mM (4.02%)\u003c/strong\u003e and \u003cstrong\u003eSA 8 mM (3.96%)\u003c/strong\u003e provided notable suppression (25.69% and 26.80% reductions, respectively). By contrast, \u003cstrong\u003echitosan treatments (4.86\u0026ndash;4.95%)\u003c/strong\u003e yielded only modest reductions (9.28\u0026ndash;10.17%).At \u003cstrong\u003e83 DAS\u003c/strong\u003e, the control plots recorded the highest incidence (\u003cstrong\u003e8.50%\u003c/strong\u003e). Once again, \u003cstrong\u003eJA 5 mM (6.23%)\u003c/strong\u003e provided maximum protection, achieving a \u003cstrong\u003e26.82% reduction\u003c/strong\u003e (\u003cem\u003eF\u003csub\u003e8,45\u003c/sub\u003e\u003c/em\u003e= 8.03; P\u0026lt;0.000). \u003cstrong\u003eSA 16 mM (6.44%, 24.24% reduction)\u003c/strong\u003e and \u003cstrong\u003eJA 2.5 mM (6.56%, 22.82% reduction)\u003c/strong\u003e followed. Moderate reductions were observed with \u003cstrong\u003eSA 8 mM (6.81%, 19.88% reduction)\u003c/strong\u003e\u003cstrong\u003e, \u003cstrong\u003eMeSA 16 mM (6.83%, 20.00% reduction)\u003c/strong\u003e\u003c/strong\u003e, and \u003cstrong\u003eMeSA 8 mM (6.95%, 18.24% reduction)\u003c/strong\u003e. \u003cstrong\u003eChitosan (7.52\u0026ndash;7.61%)\u003c/strong\u003ewas again least effective, reducing incidence by only 10.35\u0026ndash;11.53%.At \u003cstrong\u003e90 DAS\u003c/strong\u003e, the control reached its peak incidence \u003cstrong\u003e(\u003cstrong\u003e8.93%\u003c/strong\u003e).\u003c/strong\u003e The strongest suppression was recorded with \u003cstrong\u003eJA 5 mM (6.60%)\u003c/strong\u003e, corresponding to a \u003cstrong\u003e26.09% reduction\u003c/strong\u003e (\u003cem\u003eF\u003csub\u003e8,45\u003c/sub\u003e\u003c/em\u003e= 6.65; P\u0026lt;0.000). This was followed by \u003cstrong\u003eSA 16 mM (7.10%, 20.60% reduction)\u003c/strong\u003e and \u003cstrong\u003eJA 2.5 mM (7.24%, 18.90% reduction)\u003c/strong\u003e. Intermediate reductions were noted in \u003cstrong\u003eMeSA 16 mM (7.23%, 19.05%)\u003c/strong\u003e, \u003cstrong\u003eMeSA 8 mM (7.25%, 18.81%)\u003c/strong\u003e, and \u003cstrong\u003eSA 8 mM (7.48%, 16.85%)\u003c/strong\u003e. The lowest effectiveness was observed in \u003cstrong\u003echitosan (8.06\u0026ndash;8.10%)\u003c/strong\u003e, which reduced incidence by only 9.30\u0026ndash;9.75% compared with control (Fig. 4; \u003cstrong\u003eSupplement table 2\u003c/strong\u003e).\u003c/p\u003e\n\u003cp\u003eGrain yield reflected the extent of pest suppression. The highest yield was obtained with \u003cstrong\u003eJA 5 mM (4763.75 kg ha⁻\u0026sup1;)\u003c/strong\u003e, representing a \u003cstrong\u003e28.87% increase\u003c/strong\u003e over control (\u003cem\u003eF\u003csub\u003e8,26\u003c/sub\u003e\u003c/em\u003e= 1,294,592.83; P\u0026lt;0.000). This was followed by \u003cstrong\u003eJA 2.5 mM (3872.22 kg ha⁻\u0026sup1;, 12.49% increase)\u003c/strong\u003e and \u003cstrong\u003eSA 16 mM (3877.78 kg ha⁻\u0026sup1;, 12.62% increase)\u003c/strong\u003e. Moderate gains were achieved with \u003cstrong\u003eMeSA 16 mM (3851.89 kg ha⁻\u0026sup1;, 12.03%)\u003c/strong\u003e\u003cstrong\u003e, \u003cstrong\u003eSA 8 mM (3687.33 kg ha⁻\u0026sup1;, 8.10%)\u003c/strong\u003e\u003c/strong\u003e, and \u003cstrong\u003eMeSA 8 mM (3648.72 kg ha⁻\u0026sup1;,7.13%)\u003c/strong\u003e. The least improvement was observed with \u003cstrong\u003echitosan (3561.11\u0026ndash;3605.56 kg ha⁻\u0026sup1;)\u003c/strong\u003e, corresponding to only \u003cstrong\u003e4.85\u0026ndash;6.02% increase\u003c/strong\u003e over the control (Fig. 3; \u003cstrong\u003eSupplement table 2\u003c/strong\u003e).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eLaboratory experiments\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eComparative analysis of volatile profiles in pink stem borer\u0026ndash;infested, JA-treated, and untreated wheat seedlings\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHealthy wheat seedlings emitted a relatively simple volatile blend comprising twelve compounds, whereas pink stem borer (PSB) infestation expanded the profile to twenty-two compounds, and exogenous JA application induced the most diverse response with twenty-eight compounds.\u003c/p\u003e\n\u003cp\u003eIn healthy seedlings, the volatile spectrum was dominated by nitrogenous and aromatic compounds such as 3,5-dimethyl-pyrazol-1-yl-[1,2,5]oxadiazolo (40.08 \u0026plusmn; 0.50% area) and 4-(4,7-dimethoxy-2H-1,3-benzodioxol-5-yl)-1,3-dimethyl-4H,5H,7H-pyrazolo[3,4-b]pyridin-6-one (16.75\u0026plusmn;0.44%). Several mid-polar volatiles including cis-1-chloro-9-octadecene (11.73\u0026plusmn;0.44%) and benzenedicarboxylic acid bis(2-methylpropyl) ester (9.07\u0026plusmn;0.63%) were also abundant. Hydrocarbons such as 1-hexen-4-yne and octadecane,5-methyl- occurred only in trace amounts (\u0026lt;3%) (\u003cstrong\u003eSupplement table 3\u003c/strong\u003e).\u003c/p\u003e\n\u003cp\u003eUpon PSB infestation, the chemical profile shifted towards fatty acids and esters. Oxirane, hexadecyl- (11.0\u0026plusmn;0.44%), 2-butenedioic acid monododecyl ester (8.28\u0026plusmn;0.50%), and 4-nitro-5,6,7,8-tetrahydronaphthalen-1-ol (7.85\u0026plusmn;0.44%) became the most abundant volatiles. The hydrocarbon fraction was enriched with 1-nonadecene (5.50\u0026plusmn;0.50%) and tetracosane (3.37\u0026plusmn;0.44%). Notably, several nitrogen- and oxygen-rich compounds present in healthy seedlings (e.g., pyrazolyloxadiazole and benzodioxol derivatives) were absent under infestation, indicating a qualitative reconfiguration of the volatile blend (\u003cstrong\u003eSupplement table S3\u003c/strong\u003e).\u003c/p\u003e\n\u003cp\u003eJA elicitation further diversified the bouquet, eliciting unique volatiles absent in both healthy and infested plants. Nonadecylheptafluorobutyrate (7.83\u0026plusmn;0.63%), oxirane, hexadecyl- (9.80 \u0026plusmn; 0.50%), and tetracosane (4.69\u0026plusmn;0.50%) were highly abundant, alongside strong emissions of benzenedicarboxylic acid bis(2-methylpropyl) ester (11.11\u0026plusmn;0.44%) and eicosanoic acid methyl ester (5.99\u0026plusmn;0.44%). Hydrocarbon emissions were more pronounced under JA, with octadecane,5-methyl- reaching 4.21\u0026plusmn;0.50% compared to \u0026lt;1% in controls. Importantly, 5,5-diethylpentadecane was uniquely induced by JA, highlighting elicitor-specific metabolic activation (\u003cstrong\u003eSupplement table S3\u003c/strong\u003e). Retention time comparisons revealed that certain compounds appeared at multiple peaks, likely reflecting branched-chain isomers or structural analogues (e.g., methylated derivatives of tetracosane). Although the mass spectra were similar, subtle structural differences caused elution at distinct retention times. Overall, the transition from healthy to infested to JA-treated plants reflects a progression from nitrogenous/aromatic dominance to ester- and hydrocarbon-enriched blends. JA elicitation not only amplified the relative abundance of several PSB-induced compounds but also induced novel volatiles, resulting in the most complex and diverse VOC profile.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eIdentification of promising plant volatiles enhancing foraging behavior of\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003cem\u003e\u003cstrong\u003eT. chilonis\u003c/strong\u003e\u003c/em\u003e\u003cstrong\u003e\u003cem\u003e\u0026nbsp;via choice assay\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003e\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFour synthetic plant volatiles, predominantly identified in volatile profiles induced by pink stem borer (PSB) infestation and JA treatment in wheat seedlings, were selected for laboratory evaluation. These compounds were consistently abundant in the GC\u0026ndash;MS profiles and have been reported in the literature as ecologically active hydrocarbons or fatty acids influencing parasitoid and predator behavior. Their selection was therefore guided by both quantitative abundance and functional relevance, making them biologically meaningful candidates for assessing effects on the foraging behavior of \u003cem\u003eT. chilonis\u003c/em\u003e.\u003c/p\u003e\n\u003cp\u003eChoice assays were conducted to determine the influence of these volatiles on parasitoid host-searching relative to hexane-washed \u003cem\u003eCorcyra\u003c/em\u003e eggs (devoid of natural kairomones) and untreated eggs retaining natural cues. Among the compounds tested, \u003cstrong\u003eeicosane (200 ppm)\u003c/strong\u003eelicited the strongest attraction, with a parasitization rate of \u003cstrong\u003e91.8%\u003c/strong\u003e (\u003cem\u003eF₅,₁₇\u003c/em\u003e= 7253.69; P\u0026lt;0.000) seven days after parasitoid release, despite the absence of natural kairomones. This response was closely followed by \u003cstrong\u003eoctadecane (90.4%)\u0026nbsp;\u003c/strong\u003eand \u003cstrong\u003en-hexadecanoic acid (89.4%)\u003c/strong\u003e, both comparable to untreated \u003cem\u003eCorcyra\u003c/em\u003e eggs naturally emitting kairomones (90.2%). By contrast, hexane-washed eggs without volatile application exhibited a significantly lower parasitization rate of \u003cstrong\u003e25.3%\u003c/strong\u003e at the same time point (Fig. 5; \u003cstrong\u003eSupplement table 4\u003c/strong\u003e).\u003c/p\u003e\n\u003cp\u003eThe four selected volatiles were re-tested at \u003cstrong\u003e500 ppm\u003c/strong\u003e to examine concentration-dependent effects on the foraging efficiency of \u003cem\u003eT. chilonis\u003c/em\u003e. At this higher dose, the greatest parasitization (94.5%) was recorded on unwashed \u003cem\u003eC. cephalonica\u003c/em\u003e eggs seven days after parasitoid release. Parasitization on eggs treated with \u003cstrong\u003eoctadecane (92.5%)\u003c/strong\u003e and \u003cstrong\u003en-hexadecanoic acid (90.4%)\u003c/strong\u003e was statistically similar to that on unwashed eggs, whereas \u003cstrong\u003eeicosane\u003c/strong\u003e induced a high but comparatively lower parasitization rate (\u003cstrong\u003e82.5%\u003c/strong\u003e). By contrast, hexane-washed eggs lacking natural kairomones supported only \u003cstrong\u003e28.1%\u003c/strong\u003eparasitization at day seven (Fig. 6; \u003cstrong\u003eSupplement table S5\u003c/strong\u003e).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe escalating limitations of synthetic pesticides, including resistance development and ecological risks, have intensified the search for sustainable crop protection alternatives (Pawar et al. 2023). In this study, foliar application of jasmonic acid (JA) provided consistent protection against the pink stem borer (\u003cem\u003eSesamia inferens\u003c/em\u003e) across two growing seasons, significantly reducing both \u0026lsquo;dead heart\u0026rsquo; and \u0026lsquo;white ear\u0026rsquo; symptoms while enhancing grain yield. These findings demonstrate that elicitor-mediated activation of plant defenses can deliver agronomically meaningful outcomes under field conditions. Notably, JA at 5 mM reduced pest incidence by more than 30% and increased yield by nearly 29%, outperforming other elicitors tested. This result aligns with earlier reports of JA-induced resistance against \u003cem\u003eHaplothrips tritici\u003c/em\u003e and \u003cem\u003eSitodiplosis mosellana\u003c/em\u003e in wheat (El-Wakeil et al. \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2010\u003c/span\u003e), and resistance to \u003cem\u003eSitobion avenae\u003c/em\u003e (Cao et al. \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2014\u003c/span\u003e), confirming the broad utility of jasmonates in cereal protection.\u003c/p\u003e\u003cp\u003eThe present results also highlight the relevance of salicylic acid (SA) and methyl salicylate (MeSA), both of which reduced stem borer symptoms at higher concentrations. The requirement for elevated doses is consistent with the naturally high endogenous salicylate levels in cereals, which can dampen responsiveness to lower external applications (Stella de Freitas et al., 2019). Our findings align with observations of MeSA-induced resistance in barley against \u003cem\u003eRhopalosiphum padi\u003c/em\u003e (Ninkovic et al. 2021) and in rice against stink bugs (Stella de Freitas et al. 2019). Conversely, chitosan treatments were relatively ineffective, corroborating earlier evidence that chitosan is more effective against pathogens than insect pests (Li et al., \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2016\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eVolatile profiling revealed that both JA application and pink stem borer infestation induced complex blends of volatile organic compounds (VOCs), with several hydrocarbons in common. JA-treated plants emitted the most diverse profile, including octadecane, eicosane, and n-hexadecanoic acid, which were also abundant in herbivore-induced blends. This mirrors earlier findings where jasmonates or MeSA treatments triggered VOC emissions in wheat, altering the behavior of herbivores and parasitoids (Xiao et al. 2022). Similar elicitor-mediated induction of volatiles has been reported in maize (Cofer et al. \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2018\u003c/span\u003e), barley (Ninkovic et al. 2021), tomato (Kawazu et al. \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2012\u003c/span\u003e), and other systems (Thaler et al. 2001; Gordy et al. \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). Although some studies have cautioned that defense induction may incur yield penalties due to metabolic costs (Redman et al. 2001; Kawazu et al. \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2012\u003c/span\u003e), our results suggest that in wheat, JA-mediated defense can be achieved without compromising productivity.\u003c/p\u003e\u003cp\u003eThe ecological relevance of JA-induced volatiles was confirmed through behavioral assays with \u003cem\u003eTrichogramma chilonis\u003c/em\u003e. Eicosane and octadecane significantly enhanced parasitoid foraging, achieving parasitism levels comparable to eggs with natural kairomones. This is consistent with reports of hydrocarbons such as tricosane, docosane, and tetratriacontane serving as kairomones for \u003cem\u003eTrichogramma\u003c/em\u003e spp. (Srivastava et al. 2008; Parthiban et al. 2016). Similar kairomonal activity of herbivore-induced volatiles has been documented in chickpea (Romeis et al. 1999), rice (Murali-Baskaran et al. \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2020\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2021\u003c/span\u003e), and chilli (Vijaya et al. 2018). The dose-dependent effects observed in our assays, where higher concentrations occasionally reduced attraction, agree with earlier observations that parasitoid responses to hydrocarbons are concentration sensitive (Paul et al. 2008; Parthiban et al. 2016).\u003c/p\u003e\u003cp\u003eTogether, these findings reinforce the concept that elicitor-mediated volatile induction not only suppresses herbivores directly but also enhances the efficiency of biological control agents. Such dual roles make elicitors promising candidates for integration into pest management programs. Previous studies have highlighted the potential of exogenous chemical elicitors in disease and insect pest management (Holopainen et al. \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2009\u003c/span\u003e; Haas and Bostock \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; War et al. 2015), and our work extends this by demonstrating field-level efficacy against a major wheat pest. By linking crop protection outcomes with mechanistic insights into volatile-mediated tritrophic interactions, this study provides an applied framework for incorporating elicitor sprays into wheat Integrated Pest Management (IPM).\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThe detrimental consequences associated with the indiscriminate use of synthetic chemical pesticides have catalyzed a paradigm shift towards environmentally sustainable pest management strategies. Among these, the application of synthetic plant volatiles has shown promising efficacy, particularly in the realm of plant-pathogen interactions. In recent years, there has been a notable surge in research exploring the potential of synthetic elicitors for crop protection. In the present investigation, foliar application of jasmonic acid (JA) at 5 mM concentration, administered twice on the 35th and 45th days post-sowing, significantly mitigated damage symptoms inflicted by the pink stem borer (\u003cem\u003eSesamia inferens\u003c/em\u003e), while concomitantly enhancing grain yield. Moreover, exogenous application of JA elicited volatile emissions in wheat seedlings analogous to those induced by pink stem borer infestation. Among the four predominant volatiles identified, eicosane and octadecane notably stimulated the foraging activity of the egg parasitoid \u003cem\u003eT\u003c/em\u003e. \u003cem\u003echilonis\u003c/em\u003e, comparable to the attraction elicited by natural kairomones from untreated host eggs. These findings underscore the potential of jasmonic acid as a viable ecological alternative to conventional insecticides, offering a dual advantage of suppressing \u003cem\u003eS. inferens\u003c/em\u003e infestation and augmenting the biological control efficacy through parasitoid attraction. Foliar-applied JA thus emerges as a promising tool in the integrated pest management (IPM) framework for sustainable wheat cultivation.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eStudent and advisory committee are thankful to the Indian Council of Agricultural Research, DARE, New Delhi and the ICAR-National Institute of Biotic Stress Management, Raipur for financial support and other logistics for conducting the present research both under field and laboratory conditions.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAuthors are grateful to the Indian Council of Agricultural Research (ICAR), DARE, New Delhi which has provided funds for conducting field experiments. This is contribution of ICAR-NIBSM/Rp-49/2023-06.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eRKMB: Conceptualization and identification of research problem, development of methodology, writing of paper, review; MR: Conduct of field and lab experiments, collection and curing of field and lab data.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical approval and consent to participate\u0026nbsp;\u003c/strong\u003eThis research paper does not report or involve the use of any animal or human data or tissue.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Publish and Participate\u0026nbsp;\u003c/strong\u003eThe authors do not report any individual details, images, or videos in this research paper.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u0026nbsp;\u003c/strong\u003eThe authors declare that they have no competing interests.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data used in the manuscript are given in the table file, and main text\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eAslam H, Mushtaq S, Maalik S, Bano N, Eed EM, Bibi A, TahirA, Ijaz I, Tanwir S, Khalifa AS (2022) Exploring the effect of jasmonic acid for aphid control for improving the yield of \u003cem\u003eTriticum aestivum\u003c/em\u003e varieties. \u003cem\u003ePeerJ\u0026nbsp;\u003c/em\u003e10: e14018. https://doi.org/10.7717/peerj.14018\u003c/li\u003e\n \u003cli\u003eBhowmik P, Rudra, BC (2017) Assessment of Infestation by \u003cem\u003eSesamia inferens\u0026nbsp;\u003c/em\u003eon wheat varieties under different tillage conditions. 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Sharma HC (2015) Induced resistance to \u003cem\u003eHelicoverpa armigera\u003c/em\u003e through exogenous application of jasmonic acid and salicylic acid in groundnut, \u003cem\u003eArachis hypogaea\u003c/em\u003e. Pest Manage Sci 71:72-82.\u003c/li\u003e\n \u003cli\u003eXiao X, Liu J, Liu Y, Wang Y, Zhan Y, Liu Y (2022 Exogenous application of a plant elicitor induces volatile emission in wheat and enhances the attraction of an aphid parasitoid \u003cem\u003eAphidius gifuensis\u003c/em\u003e. Plants11(24):3496. https://doi.org/10.3390/plants11243496\u003c/li\u003e\n \u003cli\u003eXin Z, Yu Z, Erb M, Turlings TC, Wang B, Qi J, Lou Y (2012) The broad-leaf herbicide 2, 4-dichlorophenoxyacetic acid turns rice into a living trap for a major insect pest and a parasitic wasp. New Phytol 194:498-510.\u003c/li\u003e\n \u003cli\u003e\u003cstrong\u003eZhu J, Park KC (\u003c/strong\u003e2005) Methyl salicylate, a soybean aphid-induced plant volatile attractive to the predator \u003cem\u003eCoccinella septempunctata\u003c/em\u003e. \u003cem\u003eJ Chem Ecol\u0026nbsp;\u003c/em\u003e\u003cstrong\u003e31\u003c/strong\u003e:1733\u0026ndash;1746.\u003c/li\u003e\n \u003cli\u003eZhu X, Wang Y, Zhang L (2025) Jasmonic acid signaling pathway in response to abiotic stress in wheat. \u003cem\u003eIn J Mol Sci 26\u003c/em\u003e(2):621. https://doi.org/10.3390/ijms26020621\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Triticum aestivum. Sesamia inferens . jasmonic acid. herbivore-induced plant volatiles. Trichogramma chilonis. sustainable pest management","lastPublishedDoi":"10.21203/rs.3.rs-7638087/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7638087/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eWheat (\u003cem\u003eTriticum aestivum\u003c/em\u003e L.) productivity in South Asia is increasingly constrained by the pink stem borer (\u003cem\u003eSesamia inferens\u003c/em\u003e), a lepidopteran pest responsible for severe yield losses. Conventional insecticide use often results in resistance and ecological risks, underscoring the need for environmentally sustainable alternatives. In this study, we evaluated the efficacy of four elicitors\u0026mdash;jasmonic acid (JA), salicylic acid (SA), methyl salicylate (MeSA), and chitosan\u0026mdash;in enhancing wheat resistance under field conditions across two consecutive winter seasons. Foliar application of JA (5 mM at 35 and 45 days after sowing) significantly reduced \u0026lsquo;dead heart\u0026rsquo; and \u0026lsquo;white ear\u0026rsquo; incidence by 31.7% and 27.9%, respectively, and increased grain yield by 28.9% compared with untreated controls. Gas chromatography\u0026ndash;mass spectrometry revealed that JA application and borer infestation induced complex volatile blends, with hydrocarbons such as octadecane and eicosane strongly enhancing the foraging efficiency of the egg parasitoid \u003cem\u003eTrichogramma chilonis\u003c/em\u003e in laboratory assays. These findings highlight the dual role of JA-elicited volatiles in directly suppressing pest damage and indirectly promoting biological control, offering a practical framework for integrating elicitor-based defense activation into wheat integrated pest management (IPM) strategies.\u003c/p\u003e","manuscriptTitle":"Jasmonicacid–elicited volatiles in wheat mediate pink stem borer suppression and parasitoid attraction","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-06 12:55:49","doi":"10.21203/rs.3.rs-7638087/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"99815354-97d9-41dd-8745-c1dc66bcc7e6","owner":[],"postedDate":"October 6th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-10-13T08:26:11+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-06 12:55:49","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7638087","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7638087","identity":"rs-7638087","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}