{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,20]],"date-time":"2026-03-20T08:36:58Z","timestamp":1773995818541,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,2,1]],"date-time":"2021-02-01T00:00:00Z","timestamp":1612137600000},"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>Understanding the spectral characteristics of crops in response to stress caused by weeds is a basic step in improving the precision of agricultural technologies that manage weeds in the field. This research focused on the competition between corn (Zea mays) and redroot pigweed (Amaranthus retroflexus), a common weed that strongly reduces corn yield. The aim of this research was to characterize the physiological changes that occur in corn during early growth because of crop\u2013weed competition and to examine the ability to detect the effect of competition through hyperspectral measurements. A greenhouse experiment was conducted, and corn plants were examined during early growth, with and without weed competition. Hyperspectral measurements were combined with physiological measurements to examine the reflectance and photosynthetic activity of corn. Changes were expected to appear mainly in the short-wave infrared region (SWIR) due to competition for water. Relative water content (RWC), chlorophyll content, photosynthetic rate, and stomatal conductance were reduced in the presence of weeds, and intercellular CO2 levels increased. Deeper SWIR light absorption occurred in the weed treatment as expected, accompanied by spectral changes in the visible (VIS) and near infrared (NIR) ranges. The results highlight the potential of using spectral measurements as an indicator of competition for water.<\/jats:p>","DOI":"10.3390\/rs13030513","type":"journal-article","created":{"date-parts":[[2021,2,1]],"date-time":"2021-02-01T11:40:48Z","timestamp":1612179648000},"page":"513","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Hyperspectral Reflectance and Indices for Characterizing the Dynamics of Crop\u2013Weed Competition for Water"],"prefix":"10.3390","volume":"13","author":[{"given":"Inbal","family":"Ronay","sequence":"first","affiliation":[{"name":"French Associates Institute for Agriculture and Biotechnology of Drylands, Sede Boqer Campus, Ben-Gurion University of the Negev, Beer Sheva 8499000, Israel"},{"name":"The Albert Katz International School for Desert Studies, Ben-Gurion University of the Negev, Sede Boqer Campus, Beer Sheva 8499000, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5583-1969","authenticated-orcid":false,"given":"Jhonathan E.","family":"Ephrath","sequence":"additional","affiliation":[{"name":"French Associates Institute for Agriculture and Biotechnology of Drylands, Sede Boqer Campus, Ben-Gurion University of the Negev, Beer Sheva 8499000, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hanan","family":"Eizenberg","sequence":"additional","affiliation":[{"name":"Department of Plant Pathology and Weed Research, Newe Ya\u2019ar Research Center, Agricultural Research Organization (ARO)-Volcani Center, Ramat-Yishay 30095, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dan G.","family":"Blumberg","sequence":"additional","affiliation":[{"name":"Geography and Environmental Development, Ben-Gurion University of the Negev, Beer Sheva 8410501, Israel"},{"name":"Homeland Security Institute, Ben-Gurion University of the Negev, Beer Sheva 8410501, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7704-4966","authenticated-orcid":false,"given":"Shimrit","family":"Maman","sequence":"additional","affiliation":[{"name":"Homeland Security Institute, Ben-Gurion University of the Negev, Beer Sheva 8410501, Israel"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Thenkabail, P.S. 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