Breaking the trade-off between grain yield and protein in maize: a global meta-analysis of optimized nitrogen management and environmental drivers

Breaking the trade-off between grain yield and protein in maize: a global meta-analysis of optimized nitrogen management and environmental drivers | 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 Breaking the trade-off between grain yield and protein in maize: a global meta-analysis of optimized nitrogen management and environmental drivers Xiaojun Jiang, Xinglong Wang, Nan Jiang, Wei Xiong, Xi Luo, Jing Huang This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9508936/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 5 You are reading this latest preprint version Abstract Background and aims Protein deficiency is a critical global challenge for public health and food security. The trade-off between maize grain yield (GY) and grain protein content (GPC) remains a major barrier to enhancing both food quantity and nutritional quality. While nitrogen (N) management is crucial for crop productivity, its potential to synergistically improve both GY and GPC across diverse global environments is not fully quantified. This study aims to identify optimal N practices and the environmental drivers that govern the synergy between maize yield and quality. Methods A global meta-analysis was conducted using 699 paired observations from peer-reviewed studies. Mixed-effects models were used to evaluate the effect of N management practices, soil properties and climatic factors on GY, GPC and grain protein yield (GPY). Results The controlled-release fertilizer boosted GY by 11.53% and GPC by 11.93%. Notably, increasing N application rate predominantly enhanced GPC rather than GY, while a modest reduction in N application rate (≤ 20%) did not significantly affect GY, GPC and GPY. Agronomic adjustments further strengthened these effects, with N topdressing increasing GY, GPC and GPY by 7.90%, 11.65% and 20.47%, respectively. Furthermore, these effects were more pronounced under conditions of lower soil bulk density (< 1.4 g/cm 3 ) and warmer climates (≥ 20°C). Conclusion Our findings demonstrate that shifting from conventional N application to synchronized management can achieve a win-win for maize productivity and nutritional security. These results provide a strategic framework for site-specific N management to optimize the soil-plant N balance under a changing climate. food security nitrogen fertilizer management maize grain yield protein content Full Text Supplementary Files Supplementarymaterial.docx Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 09 May, 2026 Reviewers invited by journal 05 May, 2026 Editor invited by journal 24 Apr, 2026 Editor assigned by journal 24 Apr, 2026 First submitted to journal 23 Apr, 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-9508936","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":634926354,"identity":"b3284657-a08a-4eba-acb7-b43c538e809e","order_by":0,"name":"Xiaojun Jiang","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Xiaojun","middleName":"","lastName":"Jiang","suffix":""},{"id":634926355,"identity":"17634d42-669f-4a6f-9146-b48dd9f47c1d","order_by":1,"name":"Xinglong 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The trade-off between maize grain yield (GY) and grain protein content (GPC) remains a major barrier to enhancing both food quantity and nutritional quality. While nitrogen (N) management is crucial for crop productivity, its potential to synergistically improve both GY and GPC across diverse global environments is not fully quantified. This study aims to identify optimal N practices and the environmental drivers that govern the synergy between maize yield and quality.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eA global meta-analysis was conducted using 699 paired observations from peer-reviewed studies. Mixed-effects models were used to evaluate the effect of N management practices, soil properties and climatic factors on GY, GPC and grain protein yield (GPY).\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe controlled-release fertilizer boosted GY by 11.53% and GPC by 11.93%. Notably, increasing N application rate predominantly enhanced GPC rather than GY, while a modest reduction in N application rate (\u0026le;\u0026thinsp;20%) did not significantly affect GY, GPC and GPY. Agronomic adjustments further strengthened these effects, with N topdressing increasing GY, GPC and GPY by 7.90%, 11.65% and 20.47%, respectively. Furthermore, these effects were more pronounced under conditions of lower soil bulk density (\u0026lt;\u0026thinsp;1.4 g/cm\u003csup\u003e3\u003c/sup\u003e) and warmer climates (\u0026ge;\u0026thinsp;20\u0026deg;C).\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eOur findings demonstrate that shifting from conventional N application to synchronized management can achieve a win-win for maize productivity and nutritional security. These results provide a strategic framework for site-specific N management to optimize the soil-plant N balance under a changing climate.\u003c/p\u003e","manuscriptTitle":"Breaking the trade-off between grain yield and protein in maize: a global meta-analysis of optimized nitrogen management and environmental drivers","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-05-13 06:06:58","doi":"10.21203/rs.3.rs-9508936/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"","date":"2026-05-10T02:30:36+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-05-05T15:31:23+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"Plant and Soil","date":"2026-04-24T23:50:35+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-04-24T04:10:04+00:00","index":"","fulltext":""},{"type":"submitted","content":"Plant and Soil","date":"2026-04-23T12:18:25+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"plant-and-soil","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"plso","sideBox":"Learn more about [Plant and Soil](https://www.springer.com/journal/11104)","snPcode":"11104","submissionUrl":"https://submission.nature.com/new-submission/11104/3","title":"Plant and Soil","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"375a8500-82f2-4c06-8473-d49c762835b5","owner":[],"postedDate":"May 13th, 2026","published":true,"recentEditorialEvents":[{"type":"reviewerAgreed","content":"","date":"2026-05-10T02:30:36+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-05-05T15:31:23+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-13T06:06:58+00:00","versionOfRecord":[],"versionCreatedAt":"2026-05-13 06:06:58","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9508936","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9508936","identity":"rs-9508936","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}