Phosphorus (P)-magnesium (Mg) interaction in citrus growth: High P promotes new shoot growth while accelerating old leaf symptoms in young navel orange plants under Mg deficiency

Phosphorus (P)-magnesium (Mg) interaction in citrus growth: High P promotes new shoot growth while accelerating old leaf symptoms in young navel orange plants under Mg deficiency | 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 Phosphorus (P)-magnesium (Mg) interaction in citrus growth: High P promotes new shoot growth while accelerating old leaf symptoms in young navel orange plants under Mg deficiency Yawei Hu, Yuanyuan Zhang, Fengxian Yao, Guan Guan, Gaofeng Zhou, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7955806/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 Background and aims The interaction between phosphorus (P) and magnesium (Mg) significantly influences citrus productivity, especially under Mg deficiency. This study investigated how P availability affects growth, physiological performance, and nutrient partitioning in young navel orange plants under different Mg supplies. Methods A factorial experiment with two Mg levels (deficient and sufficient) and three P supplies (low, moderate, and high) was conducted using sand-cultured navel orange plants. Growth parameters, leaf chlorophyll content, photosynthetic performance, oxidative stress markers, and mineral concentrations in different tissues were measured. Results Mg deficiency induced chlorosis and corky veins in old leaves, symptoms markedly accelerated by high P supply. Under Mg deficiency, High P reduced the old leaf biomass but promoted new shoot growth. These responses correlated with accelerated chlorophyll degradation, inhibited photosynthesis, enhanced oxidative damage, and altered nutrient levels (decreased nitrogen but increased potassium and P) in the old leaves, alongside a higher Mg concentration in the new leaves. Adequate Mg nutrition completely mitigated the negative effects of high P to the old leaves. Conclusion High P supply under Mg deficiency triggers a tissue-specific physiological trade-off, promoting old leaf senescence while stimulating new shoot growth via nutrient reallocation. Avoiding high-P inputs in Mg-limited orchards is crucial to prevent aggravating Mg deficiency and ensure sustainable citrus production. Phosphorus Magnesium Citrus Nutrient interaction Oxidative stress Full Text Supplementary Files SupplementaryInformation.pdf 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. 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-7955806","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":539045276,"identity":"d7981372-208c-4c86-a231-715e7d44834b","order_by":0,"name":"Yawei Hu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAwElEQVRIiWNgGAWjYBACxv7GhgMJFTY8jO0NRGphnnG48cCDM2lyzD0HiNTC3pDefPBh22Fj9hkJRGrhbTgIdNiZw4m9Mx9vvMFQYxNNUItkM9gv6YkzZ6cVWzAcS8ttIKTFEGKLdeLG2TlmEowNhwlrsT+Q2HAgsY05cf/NM0RqYWwAa3E2ZpzBQ6yWGWCHpckx9gD9kkCMXxj72x9//AGOysMbb3yosSGsBRkYSCSQohyihVQdo2AUjIJRMDIAAOSrTYPY1d5zAAAAAElFTkSuQmCC","orcid":"","institution":"Gannan Normal University","correspondingAuthor":true,"prefix":"","firstName":"Yawei","middleName":"","lastName":"Hu","suffix":""},{"id":539045277,"identity":"327f5fb1-7bac-425b-ae66-78bb2a71a8cb","order_by":1,"name":"Yuanyuan Zhang","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Yuanyuan","middleName":"","lastName":"Zhang","suffix":""},{"id":539045278,"identity":"fb241c5b-f2ba-4601-abf3-4c2464ab2ba0","order_by":2,"name":"Fengxian Yao","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Fengxian","middleName":"","lastName":"Yao","suffix":""},{"id":539045279,"identity":"ce73fa82-08a8-42fb-9870-0270cb52eac6","order_by":3,"name":"Guan Guan","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Guan","middleName":"","lastName":"Guan","suffix":""},{"id":539045280,"identity":"97aa0cbb-4b80-46e2-abaa-3f387e08311e","order_by":4,"name":"Gaofeng Zhou","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Gaofeng","middleName":"","lastName":"Zhou","suffix":""},{"id":539045281,"identity":"b936708a-47ed-475c-a63a-499a3989c798","order_by":5,"name":"Guidong Liu","email":"","orcid":"https://orcid.org/0000-0002-0611-6456","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Guidong","middleName":"","lastName":"Liu","suffix":""}],"badges":[],"createdAt":"2025-10-27 11:41:43","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7955806/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7955806/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":95840118,"identity":"c90d4732-7c71-4359-a22c-ce2daf87db46","added_by":"auto","created_at":"2025-11-13 13:55:10","extension":"xml","order_by":2,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":8571,"visible":true,"origin":"","legend":"","description":"","filename":"plsoPLSOD2504145.xml","url":"https://assets-eu.researchsquare.com/files/rs-7955806/v1/1320ec874b58497279f8f39c.xml"},{"id":95840123,"identity":"c01a2047-8206-494d-8488-bae3bbb63e5b","added_by":"auto","created_at":"2025-11-13 13:55:10","extension":"xml","order_by":3,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":1014,"visible":true,"origin":"","legend":"","description":"","filename":"PLSOD250414565396.go.xml","url":"https://assets-eu.researchsquare.com/files/rs-7955806/v1/338f822d7717d0f4f1be3691.xml"},{"id":95840119,"identity":"9dbc5000-de65-4bdc-8064-3b5b98eb721f","added_by":"auto","created_at":"2025-11-13 13:55:10","extension":"xml","order_by":4,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":865,"visible":true,"origin":"","legend":"","description":"","filename":"PLSOD2504145Import.xml","url":"https://assets-eu.researchsquare.com/files/rs-7955806/v1/a3a4dc7708e690490289bb92.xml"},{"id":98430004,"identity":"a30120c6-7305-4c2e-a769-44bcde5c6799","added_by":"auto","created_at":"2025-12-17 16:44:36","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1173335,"visible":true,"origin":"","legend":"","description":"","filename":"Manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7955806/v1_covered_a3d4b733-a11d-44c2-8d97-a42d8035b651.pdf"},{"id":95840125,"identity":"60d33fb8-d171-445e-864e-e2c4e3719aca","added_by":"auto","created_at":"2025-11-13 13:55:10","extension":"pdf","order_by":5,"title":"","display":"","copyAsset":false,"role":"supplement","size":288856,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryInformation.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7955806/v1/a7c0896a1fc10a181b079af7.pdf"}],"financialInterests":"","formattedTitle":"Phosphorus (P)-magnesium (Mg) interaction in citrus growth: High P promotes new shoot growth while accelerating old leaf symptoms in young navel orange plants under Mg deficiency","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"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":"Phosphorus, Magnesium, Citrus, Nutrient interaction, Oxidative stress","lastPublishedDoi":"10.21203/rs.3.rs-7955806/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7955806/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eBackground and aims The interaction between phosphorus (P) and magnesium (Mg) significantly influences citrus productivity, especially under Mg deficiency. This study investigated how P availability affects growth, physiological performance, and nutrient partitioning in young navel orange plants under different Mg supplies.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eMethods A factorial experiment with two Mg levels (deficient and sufficient) and three P supplies (low, moderate, and high) was conducted using sand-cultured navel orange plants. Growth parameters, leaf chlorophyll content, photosynthetic performance, oxidative stress markers, and mineral concentrations in different tissues were measured.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eResults Mg deficiency induced chlorosis and corky veins in old leaves, symptoms markedly accelerated by high P supply. Under Mg deficiency, High P reduced the old leaf biomass but promoted new shoot growth. These responses correlated with accelerated chlorophyll degradation, inhibited photosynthesis, enhanced oxidative damage, and altered nutrient levels (decreased nitrogen but increased potassium and P) in the old leaves, alongside a higher Mg concentration in the new leaves. Adequate Mg nutrition completely mitigated the negative effects of high P to the old leaves.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eConclusion High P supply under Mg deficiency triggers a tissue-specific physiological trade-off, promoting old leaf senescence while stimulating new shoot growth via nutrient reallocation. Avoiding high-P inputs in Mg-limited orchards is crucial to prevent aggravating Mg deficiency and ensure sustainable citrus production.\u003c/p\u003e","manuscriptTitle":"Phosphorus (P)-magnesium (Mg) interaction in citrus growth: High P promotes new shoot growth while accelerating old leaf symptoms in young navel orange plants under Mg deficiency","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-13 13:55:06","doi":"10.21203/rs.3.rs-7955806/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":"5347f18e-14df-4362-adc2-2e2184094a52","owner":[],"postedDate":"November 13th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-12-13T19:53:58+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-13 13:55:06","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7955806","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7955806","identity":"rs-7955806","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}