Credibility assessment of endophytic PGPB on iron and zinc biofortification, soil health, and yield in three different varieties of soybean

Credibility assessment of endophytic PGPB on iron and zinc biofortification, soil health, and yield in three different varieties of soybean | 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 Credibility assessment of endophytic PGPB on iron and zinc biofortification, soil health, and yield in three different varieties of soybean Vindhya Bundela, Neha Saini, Prem Ranjan, Ashish Kumar, Birendra Prasad, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8850695/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 4 You are reading this latest preprint version Abstract Endophytic microorganisms within plant tissues offer immense potential to enhance plant growth. Present study investigates the efficacy of endophytic microorganisms in promoting soybean growth and biofortification, with a focus on zinc and iron assimilation. The two most promising zinc-solubilizing and siderophore-producing endophytes, PLSD1 and PLSD6, were selected for detailed analysis. These strains were assessed for a range of plant growth-promoting traits, including phosphorus and potassium solubilization, nitrogen fixation, HCN, ammonia, EPS production, biofilm formation, indole acetic acid, gibberellic acid synthesis, and biocontrol against fungal pathogens. Strain PLSD1 excelled in solubilizing zinc oxide (14.14 ± 0.25µg/ml) as measured by AAS, while PLSD6 showed strong siderophore production (67.52 ± 2.45%). GC-MS analysis identified gluconic acid as predominant organic acid during zinc solubilization. Morphological, biochemical tests, and 16SrDNA sequencing identified PLSD6 as Pantoea ananatis and PLSD1 as Pseudomonas protegens . Pot trials with soybean varieties Pant soybean 26, Pant soybean 25, and Pant soybean 1347 revealed significant enhancements in plant height, dry matter, nodules, pods, seed yield, and harvest index due to bacterial and it consortium treatments. Additionally, these treatments improved soybean biochemical attributes, such as chlorophyll, carotenoids, nitrate reductase activity, and leghemoglobin content. Soil quality parameters, including pH, EC, organic carbon, NPK levels, and enzymatic activity, also improved under bacterial treatments. Soybeans treated with bacterial consortia exhibited the highest zinc (27.2 ± 0.566 mg/gm) and iron (33.05 ± 0.295 mg/gm) content in grains. These results underscore the potential of bacterial endophytes to significantly enhance soybean growth and zinc and iron biofortification, contributing to sustainable agricultural productivity and food security. Endophyte Biofortification Soybeans Food Security Siderophore Zinc solubilizing Full Text Additional Declarations No competing interests reported. Supplementary Files SupplementaryPaper.docx Cite Share Download PDF Status: Under Revision Version 1 posted Reviewers invited by journal 18 Feb, 2026 Editor assigned by journal 18 Feb, 2026 Submission checks completed at journal 14 Feb, 2026 First submitted to journal 11 Feb, 2026 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. 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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-8850695","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":593346322,"identity":"d7a2ec93-9768-4b7f-945a-abe134c6c357","order_by":0,"name":"Vindhya Bundela","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Vindhya","middleName":"","lastName":"Bundela","suffix":""},{"id":593346324,"identity":"27ff21cd-8d49-4bbe-ae92-1547609bd0c2","order_by":1,"name":"Neha Saini","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Neha","middleName":"","lastName":"Saini","suffix":""},{"id":593346325,"identity":"7ddb21d6-4590-4cf0-9dbd-c1819f741724","order_by":2,"name":"Prem Ranjan","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Prem","middleName":"","lastName":"Ranjan","suffix":""},{"id":593346327,"identity":"63ca2a98-7568-4b62-985e-82663a5923e2","order_by":3,"name":"Ashish Kumar","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Ashish","middleName":"","lastName":"Kumar","suffix":""},{"id":593346329,"identity":"eb376de5-5fed-45f9-8a0f-09fbb8caf918","order_by":4,"name":"Birendra Prasad","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Birendra","middleName":"","lastName":"Prasad","suffix":""},{"id":593346332,"identity":"6be5b787-990a-4f72-a517-b52a3199515e","order_by":5,"name":"M.K. 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Present study investigates the efficacy of endophytic microorganisms in promoting soybean growth and biofortification, with a focus on zinc and iron assimilation. The two most promising zinc-solubilizing and siderophore-producing endophytes, PLSD1 and PLSD6, were selected for detailed analysis. These strains were assessed for a range of plant growth-promoting traits, including phosphorus and potassium solubilization, nitrogen fixation, HCN, ammonia, EPS production, biofilm formation, indole acetic acid, gibberellic acid synthesis, and biocontrol against fungal pathogens. Strain PLSD1 excelled in solubilizing zinc oxide (14.14\u0026thinsp;\u0026plusmn;\u0026thinsp;0.25\u0026micro;g/ml) as measured by AAS, while PLSD6 showed strong siderophore production (67.52\u0026thinsp;\u0026plusmn;\u0026thinsp;2.45%). GC-MS analysis identified gluconic acid as predominant organic acid during zinc solubilization. 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