Economic performance of Parasitoid-Based Biological Control for Fall Armyworm (Spodoptera frugiperda) in Smallholder Maize Systems in Kenya

Economic performance of Parasitoid-Based Biological Control for Fall Armyworm (Spodoptera frugiperda) in Smallholder Maize Systems in Kenya | 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 Economic performance of Parasitoid-Based Biological Control for Fall Armyworm ( Spodoptera frugiperda) in Smallholder Maize Systems in Kenya Bipana Paudel Timilsena, Rimnoma Serge Ouedraogo, David P. Hughes This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8950841/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Nine years after its invasion, fall armyworm ( Spodoptera frugiperda , FAW) still remains a major constraint to maize production and food security in sub-Saharan Africa. While augmentative biological control has been promoted in national and regional FAW management strategies, evidence of its farm-level economic performance is limited. This study evaluated the agronomic and economic outcomes of using egg parasitoids ( Telenomus remus and Trichogramma chilonis ) in smallholder maize systems in Kenya. We surveyed 403 households across five agro-ecological zones, comparing parasitoid-based control against chemical pesticides and no active control using ex-post cost-benefit analysis and multivariate regression models. Results indicate that in agro-ecological Zones I-III, parasitoid-based FAW management led to significantly higher maize yields, total revenue, and net farm benefits compared with both pesticides use and no control. These economic gains were driven by improved yields and lower pest management costs, as farmers reduced pesticide and spraying labor expenses. In contrast, no significant differences in yield or economic outcomes were detected in Zones IV and V, where low seed rates constrained a yield potential. Overall, the findings demonstrate that parasitoid-based biological control is a profitable, sustainable component of integrated pest management in maize-based smallholder systems. By improving net returns while reducing reliance on synthetic pesticides, this approach offers a viable pathway for strengthening farm profitability and food security for smallholders. Agricultural Economics & Policy Entomology Agroecology Agronomy Fall armyworm Biological control Egg parasitoids Cost-benefit analysis Economics Full Text Additional Declarations The authors declare potential competing interests as follows: Conflict of Interest: DPH and Penn State University own equity in PlantVillage+ Inc., which has interests in this project via the commercialization of FAW parasitoids. Ownership of this company by DPH and the University has been reviewed by the University’s Individual Conflict of Interest and Institutional Conflict of Interest Committees and is currently being managed by the University. Other authors have no conflict of interest to disclose. Supplementary Files SupplementaryDocumentCBManuscript.pdf Cite Share Download PDF Status: Posted Version 1 posted 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-8950841","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":606385218,"identity":"70db5219-7a65-4d68-9b04-0a02c111cfa7","order_by":0,"name":"Bipana Paudel Timilsena","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAv0lEQVRIiWNgGAWjYBACAwYG9g8JFRJyEC4bcVrYGB6csTAmTQvjw7aKxAaitZhL9x57kMAmkb6d/4wBw4eyw4S1WM45l26QwCORu3NGjgHjjHNEaDG4kWMgkSAhkbvhBo8BM28b0VoMJNINzp8xYP5LpBYziYQEoK4DOQbMjMRoAfol2SDhgIThzhlpBQd7zqUT1gIMsYMPf/6rkzfnP7zxwY8ya8JaGCR4oC4E4gNEqEfTMgpGwSgYBaMAKwAAJSM740e9k2UAAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0003-3584-0563","institution":"Pennsylvania State University","correspondingAuthor":true,"prefix":"","firstName":"Bipana","middleName":"Paudel","lastName":"Timilsena","suffix":""},{"id":606385219,"identity":"2620f714-c3bd-438f-9f63-4e4fd01e0693","order_by":1,"name":"Rimnoma Serge Ouedraogo","email":"","orcid":"https://orcid.org/0000-0003-3339-300X","institution":"Pennsylvania State University","correspondingAuthor":false,"prefix":"","firstName":"Rimnoma","middleName":"Serge","lastName":"Ouedraogo","suffix":""},{"id":606385364,"identity":"667022d0-b75c-4a20-beb7-728669652b1a","order_by":2,"name":"David P. 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