Advancing phosphorus foliar fertilization with nano-hydroxyapatite: mechanisms and agricultural relevance

Advancing phosphorus foliar fertilization with nano-hydroxyapatite: mechanisms and agricultural relevance | 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 Advancing phosphorus foliar fertilization with nano-hydroxyapatite: mechanisms and agricultural relevance Francesco Minutello, Idil Ertem, Augusta Szameitat, Birte Martin-Bertelsen, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8347454/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 14 You are reading this latest preprint version Abstract Phosphorus (P) use in agriculture remains inefficient and poses long-term environmental concerns. We investigate the uptake, redistribution, and efficacy of foliar-applied nano-hydroxyapatite (nHAp) in P-deficient barley (Hordeum vulgare), aiming to clarify its mode of action and evaluate its potential as a practical alternative to conventional phosphate salts. Using a simple, low-cost wet synthesis, we produced chemically-labelled nHAp with uniform elongated morphology (median length and width of 33.6 and 5.3 nm, respectively), excellent colloidal stability, pH-dependent solubility, and full redispersibility, suitable for highly concentrated foliar formulations. Infiltration experiments reveal that nHAp dissolves gradually in situ, with peak phosphate release between 1-3 days post-treatment, enabling local and systemic P recovery in deficient plants without inducing leaf scorching, unlike conventional P fertilizers. Bioimaging reveals that nHAp, applied as droplets to the leaf surface, penetrates via stomata and diffuses through the apoplast, where it dissolves and releases P without entering mesophyll cells. Uptake efficiency was strongly influenced by formulation surface tension and air humidity, and varied markedly between crop species. When comparing barley with potato, it was shown that potato exhibited high uptake at single applications, whereas barley required repeated treatments due to lower uptake efficiency. These findings position nHAp as a promising nanobiotechnological approach for sustainable and slow-release foliar P fertilization. Nanofertilizer foliar fertilization phosphorus bioimaging Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 22 Feb, 2026 Reviews received at journal 22 Feb, 2026 Reviews received at journal 20 Feb, 2026 Reviews received at journal 11 Feb, 2026 Reviews received at journal 11 Feb, 2026 Reviewers agreed at journal 22 Jan, 2026 Reviewers agreed at journal 22 Jan, 2026 Reviewers agreed at journal 22 Jan, 2026 Reviewers agreed at journal 22 Jan, 2026 Reviewers agreed at journal 22 Jan, 2026 Reviewers invited by journal 22 Jan, 2026 Editor assigned by journal 04 Jan, 2026 Submission checks completed at journal 04 Jan, 2026 First submitted to journal 12 Dec, 2025 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. 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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-8347454","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":561019458,"identity":"381cfac4-7b30-4724-a631-dbf7ed4cceae","order_by":0,"name":"Francesco Minutello","email":"","orcid":"","institution":"University of Copenhagen","correspondingAuthor":false,"prefix":"","firstName":"Francesco","middleName":"","lastName":"Minutello","suffix":""},{"id":561019459,"identity":"721131cf-bf4c-4328-922b-f0d9dd0b6cf8","order_by":1,"name":"Idil Ertem","email":"","orcid":"","institution":"University of 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