Rapid Ragi: A speed breeding protocol for Finger millet

Rapid Ragi: A speed breeding protocol for Finger millet | 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 Rapid Ragi: A speed breeding protocol for Finger millet Sobhan Sajja, Jwala Pranati, S Shyamala, K. S. Vinutha, Ramya Reddy, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6399595/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 12 Jun, 2025 Read the published version in Plant Methods → Version 1 posted 16 You are reading this latest preprint version Abstract Background : Climate change is gradually increasing demand for resilient, nutritious crops like finger millet or ragi. Ensuring food security requires researchers to develop improved and adapted cultivars rapidly. Modern techniques such as genomics-assisted breeding have emerged in the previous decade and combined with rapid generation advancement they will offer a step change in the speed of cultivar development. Results : In this study, we developed a repeatable and cost-effective speed breeding protocol for finger millet by modulating the agronomic and physiological components for early generation advancement. A photoperiod of 9-hours, 29±2℃ temperature, 70% relative humidity, 105 plants per 1.5 sq. ft., 0.17% Hoagland’s No. 2 solution spray, restricted irrigation and harvesting at physiological maturity successfully reduced 28-54 days across the maturity groups of finger millet. The advantage was validated in segregating populations confirming up to 4-5 generations a year, instead of 1-2 under field conditions. Conclusion : The speed breeding protocol developed reduces the breeding cycle time significantly allowing increased genetic gain. The protocol provides the advantage of rapid development of recombinant inbred lines (RILs), high-throughput phenotyping for biotic and abiotic stresses, and genotyping for early generation selections. Finger millet Speed breeding Photoperiod Rapid generation advancement Short-day plant High-density planting Full Text Additional Declarations No competing interests reported. Supplementary Files Supplementarytablesandfigures.docx Cite Share Download PDF Status: Published Journal Publication published 12 Jun, 2025 Read the published version in Plant Methods → Version 1 posted Editorial decision: Revision requested 03 May, 2025 Reviews received at journal 02 May, 2025 Reviews received at journal 01 May, 2025 Reviews received at journal 01 May, 2025 Reviews received at journal 01 May, 2025 Reviewers agreed at journal 12 Apr, 2025 Reviewers agreed at journal 12 Apr, 2025 Reviewers agreed at journal 12 Apr, 2025 Reviewers agreed at journal 12 Apr, 2025 Reviewers agreed at journal 12 Apr, 2025 Reviewers agreed at journal 11 Apr, 2025 Reviewers agreed at journal 10 Apr, 2025 Reviewers invited by journal 10 Apr, 2025 Editor assigned by journal 09 Apr, 2025 Submission checks completed at journal 09 Apr, 2025 First submitted to journal 08 Apr, 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. 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