Morphometric, Physiological, and Proteomic Insights into Drought Stress Mitigation in Big Leaf Mahogany: The Role of Defense Hormones JA and SA in Enhancing Stress Resilience

Morphometric, Physiological, and Proteomic Insights into Drought Stress Mitigation in Big Leaf Mahogany: The Role of Defense Hormones JA and SA in Enhancing Stress Resilience | 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 Morphometric, Physiological, and Proteomic Insights into Drought Stress Mitigation in Big Leaf Mahogany: The Role of Defense Hormones JA and SA in Enhancing Stress Resilience Karthik KC, Manju Elizabeth P, Santhoshkumar A V, Binu N Kamalolbhavan, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5763391/v2 This work is licensed under a CC BY 4.0 License Status: Posted Version 2 posted You are reading this latest preprint version Show more versions Abstract Drought stress is a major abiotic constraint affecting growth and productivity in tropical forestry species such as Swietenia macrophylla (mahogany). This study investigates the morphometric, physiological, biochemical, and proteomic responses of mahogany seedlings to drought and evaluates the ameliorative potential of two defense hormones—Jasmonic Acid (JA) and Salicylic Acid (SA). Seedlings were subjected to three phases: pre-drought (well-watered), drought (25% field capacity), and recovery (rehydration with foliar application of 0.6 mM JA or 0.8 mM SA). Drought stress significantly reduced photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), pigment content, and relative water content (RWC), while enhancing proline and superoxide dismutase accumulation and altering protein expression profiles. Exogenous hormone application mitigated these effects, with JA showing superior efficacy in restoring growth traits, physiological function, and pigment levels compared to SA. Proteomic analysis revealed drought-induced downregulation of photosynthetic and metabolic proteins such as RuBisCO and DAHP synthase, along with upregulation of stress-responsive proteins including Heat Shock Protein 90 (HSP90) and sulfiredoxin. Hormonal treatments reversed these patterns, promoting the accumulation of proteins associated with photosynthesis and stress defense. Gene Ontology (GO) enrichment highlighted the involvement of photosynthetic processes, metabolic reprogramming, and reactive oxygen species (ROS) scavenging in drought adaptation. Overall, the findings demonstrate that JA and SA play complementary roles in alleviating drought stress, with JA being more effective, and provide valuable insights for enhancing stress resilience in tropical tree species through targeted hormonal interventions. Forestry Abiotic Stress Drought Defense hormones Proteomic analysis Jasmonic acid and Swietenia macrophylla Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Full Text Additional Declarations The authors declare no competing interests. Supplementary Files Tables1.pdf 1-5 Cite Share Download PDF Status: Posted Version 2 posted You are reading this latest preprint version Show more versions 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. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5763391","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":405421646,"identity":"793dea27-56cb-4391-8924-97ee4612e405","order_by":0,"name":"Karthik KC","email":"data:image/png;base64,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","orcid":"https://orcid.org/0009-0008-5750-1160","institution":"KAU: Kerala Agricultural University","correspondingAuthor":true,"prefix":"","firstName":"Karthik","middleName":"","lastName":"KC","suffix":""},{"id":405421647,"identity":"f9f9ae34-a1c8-4c54-834f-a0b0ced5b056","order_by":1,"name":"Manju Elizabeth P","email":"","orcid":"","institution":"Kerala Agricultural University","correspondingAuthor":false,"prefix":"","firstName":"Manju","middleName":"Elizabeth","lastName":"P","suffix":""},{"id":405421648,"identity":"ef1b0466-fe97-413c-b519-b09bac3e7204","order_by":2,"name":"Santhoshkumar A V","email":"","orcid":"","institution":"Kerala Agricultural University","correspondingAuthor":false,"prefix":"","firstName":"Santhoshkumar","middleName":"A","lastName":"V","suffix":""},{"id":405421649,"identity":"568dc30a-6e38-4b7d-8c32-118eee11ec5f","order_by":3,"name":"Binu N Kamalolbhavan","email":"","orcid":"","institution":"Kerala Agricultural University","correspondingAuthor":false,"prefix":"","firstName":"Binu","middleName":"N","lastName":"Kamalolbhavan","suffix":""},{"id":405421651,"identity":"7d3b946b-d656-420d-b758-580f1cfc625a","order_by":4,"name":"Ashwath MN","email":"","orcid":"","institution":"University of Agriculture Sciences Raichur: University of Agricultural Sciences Raichur","correspondingAuthor":false,"prefix":"","firstName":"Ashwath","middleName":"","lastName":"MN","suffix":""},{"id":405421654,"identity":"58274d47-d61d-42b6-b25d-6e45635fba51","order_by":5,"name":"Delphy Rocha","email":"","orcid":"","institution":"Kerala Agricultural University","correspondingAuthor":false,"prefix":"","firstName":"Delphy","middleName":"","lastName":"Rocha","suffix":""},{"id":405421655,"identity":"75d4b265-40ac-4c3f-ac4f-d68e58364ded","order_by":6,"name":"Keisham Bindyalaxmi","email":"","orcid":"","institution":"Kerala Agricultural University","correspondingAuthor":false,"prefix":"","firstName":"Keisham","middleName":"","lastName":"Bindyalaxmi","suffix":""}],"badges":[],"createdAt":"2025-01-04 12:01:59","currentVersionCode":2,"declarations":{"humanSubjects":false,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":false,"humanSubjectConsent":false,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-5763391/v2","doiUrl":"https://doi.org/10.21203/rs.3.rs-5763391/v2","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":80400007,"identity":"9ebf14ce-4891-44cf-8b52-62ae087ae3f5","added_by":"auto","created_at":"2025-04-11 13:25:35","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1188765,"visible":true,"origin":"","legend":"\u003cp\u003eVisual representation of Swietenia macrophylla seedlings under (A) Pre-drought condition, (B) Drought condition (25% FC), and (C) Recovery stage under different treatments: Control, SA (0.8 mM), and JA (0.6 mM).\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-5763391/v2/4aee98968cf783634620568c.png"},{"id":80400358,"identity":"1d973111-9b12-40df-b9ab-937dd13a82df","added_by":"auto","created_at":"2025-04-11 13:33:35","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":236908,"visible":true,"origin":"","legend":"\u003cp\u003ePhysiological changes in defense hormone-mediated drought response in Swietenia macrophylla seedlings. (A) Net photosynthetic rate (Pn), (B). Stomatal conductance (Gs), (C) Transpiration rate (D) Chlorophyll a, (E) Chlorophyll b and (F). Total Chlorophyll content. The data were analyzed by one-way ANOVA combined with LSD test. Bars followed by the different letters are significantly different by LSD test at P \u0026lt; 0.05 (± SE, n = 25)\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-5763391/v2/6073801c23b84bf2fe674b69.png"},{"id":80400009,"identity":"6d1e32b4-fcf8-4db5-b45a-322c2ac06be7","added_by":"auto","created_at":"2025-04-11 13:25:35","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":324395,"visible":true,"origin":"","legend":"\u003cp\u003ePhysiological and biochemical changes in defense hormone-mediated drought response in Swietenia macrophylla seedlings. (G) Carotenoid content, (H). Relative water content (RWC), (I) Proline content, (J) Superoxide dismutase (SOD), (K) Chlorophyll Stability Index (CSI), (L) Membrane Stability Index (MSI) The data were analyzed by one-way ANOVA combined with LSD test. Bars followed by the different letters are significantly different by LSD test at P \u0026lt; 0.05 (± SE, n = 25)\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-5763391/v2/f08bca3ebc366028f4a92a90.png"},{"id":80400014,"identity":"52dc8e64-a219-412c-b4d0-2a0b87f22df5","added_by":"auto","created_at":"2025-04-11 13:25:35","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":221518,"visible":true,"origin":"","legend":"\u003cp\u003ePCA biplot depicting the distribution of different morphometric, physiological and biochemical parameters during the recovery phase of drought response in Swietenia macrophylla seedlings.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-5763391/v2/09efcb8bc0a66e0ba180e22a.png"},{"id":80401482,"identity":"5456c1e9-aa0d-4fc9-ac0e-b01dbeb8430b","added_by":"auto","created_at":"2025-04-11 13:49:35","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":379948,"visible":true,"origin":"","legend":"\u003cp\u003eSDS-PAGE protein bands for different conditions under drought stress in Swietenia macrophylla seedlings\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-5763391/v2/8cd3eb571f804a0a8e03d91c.png"},{"id":80400017,"identity":"aadfc476-2c12-4885-963e-c33900b62ab2","added_by":"auto","created_at":"2025-04-11 13:25:35","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":211957,"visible":true,"origin":"","legend":"\u003cp\u003eClustered heatmap depicting the differential expression of proteins under various drought stress conditions. \"Normal\" represents the pre-drought condition, \"Drought\" indicates the drought stress condition, \"RC\" refers to recovery without hormone treatment, \"SA\" denotes recovery with Salicylic Acid (0.8mM) treatment, and \"JA\" signifies recovery with Jasmonic Acid (0.6mM) treatment.\u003c/p\u003e","description":"","filename":"image.png","url":"https://assets-eu.researchsquare.com/files/rs-5763391/v2/b2cb4482b2d860343378fdf6.png"},{"id":80400359,"identity":"861a3e31-b839-4e0b-99aa-ada200f4e81e","added_by":"auto","created_at":"2025-04-11 13:33:35","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":187503,"visible":true,"origin":"","legend":"\u003cp\u003eFunctional annotation of differentially expressed proteins for different conditions under drought stress\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-5763391/v2/f7b24ee5f13f06eb6a44f001.png"},{"id":80402178,"identity":"dbd5a610-bad2-44b2-9ba6-0688b4d61895","added_by":"auto","created_at":"2025-04-11 13:57:36","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":311174,"visible":true,"origin":"","legend":"\u003cp\u003eProtein–protein interaction (PPI) network analysis of significantly expressed proteins in Swietenia macrophylla leaves under drought stress, constructed using the STRING database. The colored lines represent different types of predicted associations: neighbourhood (green), gene co-occurrence (blue), co-expression (black), experimental evidence (purple), curated databases (light blue), and text mining (yellow). Disconnected nodes (proteins not linked to the main network) were omitted for clarity.\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-5763391/v2/a8ecd13a2cfc95b4c272b12f.png"},{"id":80400368,"identity":"63cad6d6-1a2e-4d23-a406-ce395a4e64fe","added_by":"auto","created_at":"2025-04-11 13:33:36","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":274603,"visible":true,"origin":"","legend":"\u003cp\u003eProtein concentration(mg/g) changes during different stress conditions in Swietenia macrophylla seedlings. \"Normal\" represents the pre-drought condition, \"Drought\" indicates the drought stress condition, \"RC\" refers to recovery without hormone treatment, \"SA\" denotes recovery with Salicylic Acid (0.8mM) treatment, and \"JA\" signifies recovery with Jasmonic Acid (0.6mM) treatment.\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-5763391/v2/d20573189b274470d67185c5.png"},{"id":80401135,"identity":"e62a9484-cd0f-4de6-b1e4-27423ff356bc","added_by":"auto","created_at":"2025-04-11 13:41:36","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":84294,"visible":true,"origin":"","legend":"\u003cp\u003eGene Ontology (GO) classification of differentially expressed genes (DEGs) in Swietenia macrophylla: (A) Biological Processes (BP), (B) Molecular Functions (MF), and (C) Cellular Components (CC) in \u003cem\u003eSwietenia macrophylla\u003c/em\u003e seedlings.\u003c/p\u003e","description":"","filename":"10.png","url":"https://assets-eu.researchsquare.com/files/rs-5763391/v2/d8e0a8a42a5f95978b5e0840.png"},{"id":80401479,"identity":"912dc135-04b2-4d62-8b1d-3396c9c3b1d7","added_by":"auto","created_at":"2025-04-11 13:49:35","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":278010,"visible":true,"origin":"","legend":"\u003cp\u003e1-5\u003c/p\u003e","description":"","filename":"Tables1.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5763391/v2/b69d3fe0885fb30d5d6ec09c.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003eMorphometric, Physiological, and Proteomic Insights into Drought Stress Mitigation in Big Leaf Mahogany: The Role of Defense Hormones JA and SA in Enhancing Stress Resilience\u003c/p\u003e","fulltext":[],"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":true,"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":"Abiotic Stress, Drought, Defense hormones, Proteomic analysis, Jasmonic acid and Swietenia macrophylla","lastPublishedDoi":"10.21203/rs.3.rs-5763391/v2","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5763391/v2","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eDrought stress is a major abiotic constraint affecting growth and productivity in tropical forestry species such as \u003cem\u003eSwietenia macrophylla \u003c/em\u003e(mahogany). This study investigates the morphometric, physiological, biochemical, and proteomic responses of mahogany seedlings to drought and evaluates the ameliorative potential of two defense hormones—Jasmonic Acid (JA) and Salicylic Acid (SA). Seedlings were subjected to three phases: pre-drought (well-watered), drought (25% field capacity), and recovery (rehydration with foliar application of 0.6 mM JA or 0.8 mM SA). Drought stress significantly reduced photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), pigment content, and relative water content (RWC), while enhancing proline and superoxide dismutase accumulation and altering protein expression profiles. Exogenous hormone application mitigated these effects, with JA showing superior efficacy in restoring growth traits, physiological function, and pigment levels compared to SA. Proteomic analysis revealed drought-induced downregulation of photosynthetic and metabolic proteins such as RuBisCO and DAHP synthase, along with upregulation of stress-responsive proteins including Heat Shock Protein 90 (HSP90) and sulfiredoxin. Hormonal treatments reversed these patterns, promoting the accumulation of proteins associated with photosynthesis and stress defense. Gene Ontology (GO) enrichment highlighted the involvement of photosynthetic processes, metabolic reprogramming, and reactive oxygen species (ROS) scavenging in drought adaptation. Overall, the findings demonstrate that JA and SA play complementary roles in alleviating drought stress, with JA being more effective, and provide valuable insights for enhancing stress resilience in tropical tree species through targeted hormonal interventions.\u003c/p\u003e","manuscriptTitle":"Morphometric, Physiological, and Proteomic Insights into Drought Stress Mitigation in Big Leaf Mahogany: The Role of Defense Hormones JA and SA in Enhancing Stress Resilience","msid":"","msnumber":"","nonDraftVersions":[{"code":2,"date":"2025-04-11 13:25:30","doi":"10.21203/rs.3.rs-5763391/v2","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}},{"code":1,"date":"2025-01-22 06:23:26","doi":"10.21203/rs.3.rs-5763391/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":"72216bcf-1909-41af-928b-a6b50810bc84","owner":[],"postedDate":"April 11th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":45945241,"name":"Forestry"}],"tags":[],"updatedAt":"2025-02-01T02:25:58+00:00","versionOfRecord":[],"versionCreatedAt":"2025-04-11 13:25:30","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v2","identity":"rs-5763391","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5763391","identity":"rs-5763391","version":["v2"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}