Thermo-Photochemical Hysteresis Principle: A Cross-Modal Loop-Area Assay for Dynamic Plant Stress Phenotyping

Thermo-Photochemical Hysteresis Principle: A Cross-Modal Loop-Area Assay for Dynamic Plant Stress Phenotyping | 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 Thermo-Photochemical Hysteresis Principle: A Cross-Modal Loop-Area Assay for Dynamic Plant Stress Phenotyping S M Nazmuz Sakib This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8604578/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 We present a protocol-defined, scalar, cross-modal hysteresis phenotype for plant stress phenotyping that quantifies dynamic decoupling between a thermal channel (e.g., leaf tem-perature proxy ∆T or canopy temperature) and a photochemical channel (e.g., ΦPSII, NPQ, or fluorescence-derived yields). The core measurement is a signed loop-area in a phase planespanned by the two signals under a symmetric perturbation (light or VPD ramp; option-ally sinusoidal forcing). We formalize this as the Sakib Thermo-Photochemical Hys-teresis Index (Sakib-Index) and provide mathematically grounded normalizations: the Sakib Coupling Coefficient (SCC) and the Sakib Phase-Lag Constant (SPLC). We show how loop area connects to phase-lag for periodic forcing and propose minimalcomputational checks for robustness (closure, sampling invariance, and directionality). Tendata-based illustrations are generated from open-access plant datasets (tomato chlorophyllfluorescence/reflectance and cottonwood leaf-temperature microclimate records), plus sixconceptual diagrams clarifying the assay pipeline. Plant Physiology and Morphology Botany Plant Molecular Biology and Genetics Structural Biology hysteresis chlorophyll fluorescence NPQ ΦPSII leaf temperature VPD phenotyping phase-plane loop area plant stress Full Text Additional Declarations The authors declare no competing interests. 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. 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