Integrating Intercropping, Nitrogen Fertilizer and Azospirillum spp. to Enhance Growth, Yield, and Quality of Sweet Corn-Sweet potato Systems in A Sandy Land

Integrating Intercropping, Nitrogen Fertilizer and Azospirillum spp. to Enhance Growth, Yield, and Quality of Sweet Corn-Sweet potato Systems in A Sandy Land | 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 Integrating Intercropping, Nitrogen Fertilizer and Azospirillum spp. to Enhance Growth, Yield, and Quality of Sweet Corn-Sweet potato Systems in A Sandy Land Reham M Abdalla, Eslam.M A Elhafeez, Bahy.R Bakheit, Asmaa A Mohamed This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8522642/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 12 You are reading this latest preprint version Abstract A two-year field study was conducted to examine the possibility of partially replacing the nitrogenous fertilizer with the inoculum in a sandy land without affecting the growth, yield, and quality characteristics of sweet potato-sweet corn intercropping systems. The first factor was nitrogen fertilizer: Azospirillum brasilense (Ab, T1), 100 kg N ha − 1 (half-dose of nitrogen, T2), 200 kg N ha − 1 (full dose of nitrogen, T3), Ab + 100 kg N ha − 1 (T4), Ab + 200 kg ha − 1 (T5). The second factor was the intercropping systems (IS): 1) 100%IS = sole sweet corn or sole sweet potato, 2) 75%IS = 3 rows of sweet corn + one row of sweet potato, 3) 50%IS = two rows of each crop, 4) 25%IS = one row of sweet corn + 3 rows of sweet potato. The interaction showed that all intercropping systems within T5 surpassed other treatment combinations in all studied traits, but it was comparable to the intercropping systems within T4. The lowest results were observed in all traits within the bacteria treatment (T1). The highest significant fat percentage and total solids were found in T5 + IS in sweet potato. Land equivalent ratio was greater than one in all treatment combinations, but the highest values were observed in T5 + 50%IS and T1 + 50%IS. As inoculating intercropped plants with Azospirillum spp. with either full- or half-dose of nitrogenous fertilizer under sandy land conditions had comparable growth and yield for both crops, we conclude that integrating intercropping (50%IS) with microbial inoculation and a reduced (half) nitrogen fertilizer dose can effectively lessen the reliance on synthetic nitrogen inputs. The best return is achieved by intercropping sweet potato with sweet corn at a ratio of 50% for each, using a bacteriological fertilization level + 200 N ha − 1 . Cropping systems Biofertilization Sustainable agriculture Sandy soils Crop productivity Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 05 May, 2026 Reviews received at journal 02 May, 2026 Reviewers agreed at journal 20 Apr, 2026 Reviews received at journal 12 Apr, 2026 Reviewers agreed at journal 02 Apr, 2026 Reviewers agreed at journal 14 Feb, 2026 Reviewers agreed at journal 11 Feb, 2026 Reviewers agreed at journal 24 Jan, 2026 Reviewers invited by journal 13 Jan, 2026 Editor assigned by journal 11 Jan, 2026 Submission checks completed at journal 09 Jan, 2026 First submitted to journal 06 Jan, 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. 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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-8522642","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":574256515,"identity":"0953888a-7fcc-40cc-b121-6c85c178f750","order_by":0,"name":"Reham M Abdalla","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Reham","middleName":"M","lastName":"Abdalla","suffix":""},{"id":574256516,"identity":"30b94602-374e-44d6-baca-fa43fcc3bbf7","order_by":1,"name":"Eslam.M A 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The first factor was nitrogen fertilizer: \u003cem\u003eAzospirillum brasilense\u003c/em\u003e (Ab, T1), 100 kg N ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e (half-dose of nitrogen, T2), 200 kg N ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e (full dose of nitrogen, T3), Ab\u0026thinsp;+\u0026thinsp;100 kg N ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e (T4), Ab\u0026thinsp;+\u0026thinsp;200 kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e (T5). The second factor was the intercropping systems (IS): 1) 100%IS\u0026thinsp;=\u0026thinsp;sole sweet corn or sole sweet potato, 2) 75%IS\u0026thinsp;=\u0026thinsp;3 rows of sweet corn\u0026thinsp;+\u0026thinsp;one row of sweet potato, 3) 50%IS\u0026thinsp;=\u0026thinsp;two rows of each crop, 4) 25%IS\u0026thinsp;=\u0026thinsp;one row of sweet corn\u0026thinsp;+\u0026thinsp;3 rows of sweet potato. The interaction showed that all intercropping systems within T5 surpassed other treatment combinations in all studied traits, but it was comparable to the intercropping systems within T4. The lowest results were observed in all traits within the bacteria treatment (T1). The highest significant fat percentage and total solids were found in T5\u0026thinsp;+\u0026thinsp;IS in sweet potato. Land equivalent ratio was greater than one in all treatment combinations, but the highest values were observed in T5\u0026thinsp;+\u0026thinsp;50%IS and T1\u0026thinsp;+\u0026thinsp;50%IS. As inoculating intercropped plants with \u003cem\u003eAzospirillum\u003c/em\u003e spp. with either full- or half-dose of nitrogenous fertilizer under sandy land conditions had comparable growth and yield for both crops, we conclude that integrating intercropping (50%IS) with microbial inoculation and a reduced (half) nitrogen fertilizer dose can effectively lessen the reliance on synthetic nitrogen inputs. The best return is achieved by intercropping sweet potato with sweet corn at a ratio of 50% for each, using a bacteriological fertilization level\u0026thinsp;+\u0026thinsp;200 N ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e.\u003c/p\u003e","manuscriptTitle":"Integrating Intercropping, Nitrogen Fertilizer and Azospirillum spp. to Enhance Growth, Yield, and Quality of Sweet Corn-Sweet potato Systems in A Sandy Land","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-19 18:52:01","doi":"10.21203/rs.3.rs-8522642/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-05-05T06:14:13+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-02T18:46:35+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"260348864564491338199590973998677199488","date":"2026-04-20T20:02:37+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-12T19:09:02+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"155456848806223210647411942858554737690","date":"2026-04-02T17:22:54+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"285131631842191817218538073624340984018","date":"2026-02-14T05:39:02+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"338681734651420667222535558725729844150","date":"2026-02-11T14:49:38+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"14593829672799300228600529974337222917","date":"2026-01-24T12:35:37+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-01-14T03:51:51+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-01-11T09:54:15+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-01-09T06:02:23+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of the Saudi Society of Agricultural Sciences","date":"2026-01-06T14:18:57+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-the-saudi-society-of-agricultural-sciences","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Journal of the Saudi Society of Agricultural Sciences](https://link.springer.com/journal/44447)","snPcode":"44447","submissionUrl":"https://submission.springernature.com/new-submission/44447/3","title":"Journal of the Saudi Society of Agricultural Sciences","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Open","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"9e87dbc6-154b-4e43-bceb-d9efcb34d7bf","owner":[],"postedDate":"January 19th, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Revision requested","date":"2026-05-05T06:14:13+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-05-02T18:46:35+00:00","index":40,"fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[],"tags":[],"updatedAt":"2026-05-05T06:25:37+00:00","versionOfRecord":[],"versionCreatedAt":"2026-01-19 18:52:01","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8522642","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8522642","identity":"rs-8522642","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}