{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,17]],"date-time":"2026-05-17T00:29:47Z","timestamp":1778977787057,"version":"3.51.4"},"reference-count":51,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2020,5,27]],"date-time":"2020-05-27T00:00:00Z","timestamp":1590537600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Photosynthesis performance can be assessed quantitatively with light response curves. These curves record the Electron Transport Rate (ETR) as a function of light intensity. Then, statistical fit on these curves parameterize light use efficiency, maximum photosynthetic activity and the reaction of the apparatus to stress. While this technique is performed with portable fluorometers in field conditions, it is difficult to scale it to the canopy level. The Fraunhofer line discrimination technique, which detects fluorescence signals emitted during photosynthesis, is a promising method to assess photosynthetic performance of canopies. In this study, we define a remote sensing ETR index based on a combination of three parameters: sun-induced fluorescence, normalized differential vegetation index and light intensity. Two representatives of C3 and C4 photosynthesis, L. sativa and Z. mays, experienced a fertilization concentrations gradient. ETR increased with light intensity in both crops. In L. sativa, ETR assumed a linear relationship between the photosynthetic activity and light intensity, with a correlation of R2 = 0.99 to the portable fluorometer. Additional parametrization revealed a resilience of its reaction centers to photoinhibition in maximum light intensities. When Z. mays experienced open field conditions, ETR correlated with the plant\u2019s status. While the results of this study are promising, the index still requires validation in terms of temporal track and spatial variability.<\/jats:p>","DOI":"10.3390\/rs12111718","type":"journal-article","created":{"date-parts":[[2020,5,28]],"date-time":"2020-05-28T12:36:58Z","timestamp":1590669418000},"page":"1718","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Novel Remote Sensing Index of Electron Transport Rate Predicts Primary Production and Crop Health in L. sativa and Z. mays"],"prefix":"10.3390","volume":"12","author":[{"given":"Oded","family":"Liran","sequence":"first","affiliation":[{"name":"Group of Agrophysics Studies, Migal Institute, Kiryat Shemona, Upper Galilee 11016, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ofer M.","family":"Shir","sequence":"additional","affiliation":[{"name":"Group of Computational Intelligence, Migal Institute, Kiryat Shemona, Upper Galilee 11016, Israel"},{"name":"Computer Science Department, Tel-Hai College, Kiryat Shemona, Upper Galilee 1220800, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shai","family":"Levy","sequence":"additional","affiliation":[{"name":"Group of Agrophysics Studies, Migal Institute, Kiryat Shemona, Upper Galilee 11016, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ariel","family":"Grunfeld","sequence":"additional","affiliation":[{"name":"Group of Agrophysics Studies, Migal Institute, Kiryat Shemona, Upper Galilee 11016, Israel"},{"name":"Group of Computational Intelligence, Migal Institute, Kiryat Shemona, Upper Galilee 11016, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuval","family":"Shelly","sequence":"additional","affiliation":[{"name":"Group of Agrophysics Studies, Migal Institute, Kiryat Shemona, Upper Galilee 11016, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1146\/annurev.arplant.59.032607.092759","article-title":"Chlorophyll Fluorescence: A Probe of Photosynthesis In Vivo","volume":"59","author":"Baker","year":"2008","journal-title":"Annu. 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