{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,21]],"date-time":"2026-03-21T21:04:41Z","timestamp":1774127081919,"version":"3.50.1"},"reference-count":57,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2020,12,22]],"date-time":"2020-12-22T00:00:00Z","timestamp":1608595200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100009886","name":"Apulia Region","doi-asserted-by":"publisher","award":["N. 309 Ob.Fu. 1.06.09.01.00"],"award-info":[{"award-number":["N. 309 Ob.Fu. 1.06.09.01.00"]}],"id":[{"id":"10.13039\/501100009886","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Xylella fastidiosa subsp. pauca (Xfp) is one of the most dangerous plant pathogens in the world. Identified in 2013 in olive trees in south\u2013eastern Italy, it is spreading to the Mediterranean countries. The bacterium is transmitted by insects that feed on sap, and causes rapid wilting in olive trees. The paper explores the use of Unmanned Aerial Vehicle (UAV) in combination with a multispectral radiometer for early detection of infection. The study was carried out in three olive groves in the Apulia region (Italy) and involved four drone flights from 2017 to 2019. To classify Xfp severity level in olive trees at an early stage, a combined method of geostatistics and discriminant analysis was implemented. The results of cross-validation for the non-parametric classification method were of overall accuracy = 0.69, mean error rate = 0.31, and for the early detection class of accuracy 0.77 and misclassification probability 0.23. The results are promising and encourage the application of UAV technology for the early detection of Xfp infection.<\/jats:p>","DOI":"10.3390\/rs13010014","type":"journal-article","created":{"date-parts":[[2020,12,22]],"date-time":"2020-12-22T20:39:29Z","timestamp":1608669569000},"page":"14","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Semi-Automatic Method for Early Detection of Xylella fastidiosa in Olive Trees Using UAV Multispectral Imagery and Geostatistical-Discriminant Analysis"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2301-8118","authenticated-orcid":false,"given":"Annamaria","family":"Castrignan\u00f2","sequence":"first","affiliation":[{"name":"CREA-AA\u2014Council for Agricultural Research and Economics, Via Celso Ulpiani, 5, 70125 Bari, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9227-3174","authenticated-orcid":false,"given":"Antonella","family":"Belmonte","sequence":"additional","affiliation":[{"name":"CNR-IREA National Research Council\u2014Institute for Electromagnetic Sensing of the Environment, Via Amendola, 122\/D, 70126 Bari, Italy"}]},{"given":"Ilaria","family":"Antelmi","sequence":"additional","affiliation":[{"name":"Department of Soil, Plant and Food Sciences, University of Bari\u2014Aldo Moro, Via G. Amendola 165\/A, 70126 Bari, Italy"}]},{"given":"Ruggiero","family":"Quarto","sequence":"additional","affiliation":[{"name":"Department of Earth and Geo-Environmental Sciences, University of Bari\u2014Aldo Moro, Via Edoardo Orabona, 4, 70125 Bari, Italy"}]},{"given":"Francesco","family":"Quarto","sequence":"additional","affiliation":[{"name":"PRO-GEO s.a.s., Via M. R. Imbriani 13, 76121 Barletta, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8896-5429","authenticated-orcid":false,"given":"Sameh","family":"Shaddad","sequence":"additional","affiliation":[{"name":"Soil Science Department, Faculty of Agriculture, Zagazig University, 44511 Zagazig, Egypt"}]},{"given":"Valentina","family":"Sion","sequence":"additional","affiliation":[{"name":"Department of Soil, Plant and Food Sciences, University of Bari\u2014Aldo Moro, Via G. Amendola 165\/A, 70126 Bari, Italy"}]},{"given":"Maria Rita","family":"Muolo","sequence":"additional","affiliation":[{"name":"Servizi di Informazione Territoriale S.r.l., Piazza Giovanni Paolo II, 8, 70015 Noci, Italy"}]},{"given":"Nicola A.","family":"Ranieri","sequence":"additional","affiliation":[{"name":"Servizi di Informazione Territoriale S.r.l., Piazza Giovanni Paolo II, 8, 70015 Noci, Italy"}]},{"given":"Giovanni","family":"Gadaleta","sequence":"additional","affiliation":[{"name":"Professional Agronomist, Via Carr. Lamaveta, 63\/F, 76011 Bisceglie, Italy"}]},{"given":"Edoardo","family":"Bartoccetti","sequence":"additional","affiliation":[{"name":"Salt&amp;Lemon, Piazza Mascagni 11, 10015 Ivrea, Italy"}]},{"given":"Carmela","family":"Riefolo","sequence":"additional","affiliation":[{"name":"CREA-AA\u2014Council for Agricultural Research and Economics, Via Celso Ulpiani, 5, 70125 Bari, Italy"}]},{"given":"Sergio","family":"Ruggieri","sequence":"additional","affiliation":[{"name":"CREA-AA\u2014Council for Agricultural Research and Economics, Via Celso Ulpiani, 5, 70125 Bari, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8273-0052","authenticated-orcid":false,"given":"Franco","family":"Nigro","sequence":"additional","affiliation":[{"name":"Department of Soil, Plant and Food Sciences, University of Bari\u2014Aldo Moro, Via G. 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