{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T12:51:30Z","timestamp":1772801490625,"version":"3.50.1"},"reference-count":53,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2019,3,28]],"date-time":"2019-03-28T00:00:00Z","timestamp":1553731200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100007801","name":"Fundaci\u00f3n S\u00e9neca","doi-asserted-by":"publisher","award":["20363\/PD\/17"],"award-info":[{"award-number":["20363\/PD\/17"]}],"id":[{"id":"10.13039\/100007801","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Water is not always accessible for agriculture due to its scarcity. In order to successfully develop irrigation strategies that optimize water productivity characterization of the plant, the water status is necessary. We assessed the suitability of thermal indicators by infrared thermometry (IRT) to determine the water status of grapefruit in a commercial orchard with long term irrigation using saline reclaimed water (RW) and regulated deficit irrigation (RDI) in Southeastern Spain. The results showed that Tc-Ta differences were positive in a wide range of vapor pressure deficits (VPD), and the major Tc-Ta were found at 10.00 GMT, before and after the highest daily values of VPD and solar radiation, respectively, were reached. In addition, we evaluated the relationships between Tc-Ta and VPD to establish the Non-Water Stressed Baselines (NWSBs), which are necessary to accurately calculate the crop water stress index (CWSI). Two important findings were found, which include i) the best significant correlations (p &lt; 0.005) found at 10.00 GMT and their slopes were positive, and ii) NWSBs showed a marked hourly and seasonal variation. The hourly shift was mainly explained by the variation in solar radiation since both the NWSB-slope and the NWSB-intercept were significantly correlated with a zenith solar angle (\u03b8Z) (p &lt; 0.005). The intercept was greater when \u03b8Z was close to 0 (at midday) and the slope displayed a marked hysteresis throughout the day, increasing in the morning and decreasing in the afternoon. The NWSBs determination, according to the season improved most of their correlation coefficients. In addition, the relationship significance of Tc-Ta versus VPD was higher in the period where the intercept and Tc-Ta were low. CWSI was the thermal indicator that showed the highest level of agreement with the stem water potential of the different treatments even though Tc and Tc-Ta were also significantly correlated. We highlight the suitability of thermal indicators measured by IRT to determine the water status of grapefruits under saline (RW) and water stress (RDI) conditions.<\/jats:p>","DOI":"10.3390\/rs11070757","type":"journal-article","created":{"date-parts":[[2019,3,29]],"date-time":"2019-03-29T03:38:52Z","timestamp":1553830732000},"page":"757","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":56,"title":["Determination of Crop Water Stress Index by Infrared Thermometry in Grapefruit Trees Irrigated with Saline Reclaimed Water Combined with Deficit Irrigation"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8232-5698","authenticated-orcid":false,"given":"Cristina","family":"Romero-Trigueros","sequence":"first","affiliation":[{"name":"Department of Agricultural and Environmental Science, University of Bari \u201cAldo Moro\u201d, Campus, Via Amendola 165\/A, 70126 Bari, Italy"}]},{"given":"Jos\u00e9 Mar\u00eda","family":"Bayona Gamb\u00edn","sequence":"additional","affiliation":[{"name":"Department of Irrigation, Centro de Edafolog\u00eda y Biolog\u00eda Aplicada del Segura, CSIC, P.O. Box 164, 30100 Espinardo, Murcia, Spain"}]},{"given":"Pedro Antonio","family":"Nortes Tortosa","sequence":"additional","affiliation":[{"name":"Department of Irrigation, Centro de Edafolog\u00eda y Biolog\u00eda Aplicada del Segura, CSIC, P.O. Box 164, 30100 Espinardo, Murcia, Spain"}]},{"given":"Juan Jos\u00e9","family":"Alarc\u00f3n Caba\u00f1ero","sequence":"additional","affiliation":[{"name":"Department of Irrigation, Centro de Edafolog\u00eda y Biolog\u00eda Aplicada del Segura, CSIC, P.O. Box 164, 30100 Espinardo, Murcia, Spain"}]},{"given":"Emilio","family":"Nicol\u00e1s Nicol\u00e1s","sequence":"additional","affiliation":[{"name":"Department of Irrigation, Centro de Edafolog\u00eda y Biolog\u00eda Aplicada del Segura, CSIC, P.O. Box 164, 30100 Espinardo, Murcia, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2019,3,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Field, C.B., Barros, V.R., Dokken, D.J., Mach, K.J., Mastrandrea, M.D., Bilir, T.E., Bilir, M., Chatterjee, K.L., Ebi, Y.O., and Estrada, R.C. (2014). IPCC, 2014: Climate Change 2014: Impacts, Adaptation and Vulnerability. Part A: Global and Sectoral Aspects. Contribution of Working Group II to the fifth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge University Press.","DOI":"10.1017\/CBO9781107415379"},{"key":"ref_2","unstructured":"ONU (2017). World Population Prospects. The 2017 Revision Key Findings and Advance Tables. Department of Economic and Social Affairs, Population Division, United Nations Organization (ONU). 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