{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:25:56Z","timestamp":1760149556847,"version":"build-2065373602"},"reference-count":48,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,8,17]],"date-time":"2023-08-17T00:00:00Z","timestamp":1692230400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","award":["UID\/Multi\/00631\/2013","UID\/Multi\/00631\/2019","UIDB\/00631\/2020 CEOT BASE","UIDB\/00631\/2020 CEOT PROGRAM\u00c1TICO"],"award-info":[{"award-number":["UID\/Multi\/00631\/2013","UID\/Multi\/00631\/2019","UIDB\/00631\/2020 CEOT BASE","UIDB\/00631\/2020 CEOT PROGRAM\u00c1TICO"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Forests"],"abstract":"<jats:p>The cork oak tree (Quercus suber L.) symbolizes the Montado landscape in Portugal and is a central element in the country\u2019s social and economic history. In recent decades, the loss of thousands of cork oaks has been reported, revealing the ongoing decline of these agroforestry ecosystems. This emblematic tree of the Mediterranean Basin is host to the soil-born root pathogen Phytophthora cinnamomi, an active cork oak decline driver. In this framework, the early diagnosis of trees infected by the oomycete by non-invasive methods should contribute to the sustainable management of cork oak ecosystems, which motivated this work. Gas exchange and visible\/near-infrared (400\u20131100 nm) reflectance spectroscopy measurements were conducted on leaves of both control and P. cinnamomi inoculated plants. These measurements were taken at 63, 78, 91, 126, and 248 days after inoculation. Additionally, at the end of the experiment, biochemical assays of pigments, sugars, and starch were performed. The spectroscopic measurements proved effective in distinguishing between control and inoculated plants, while the standard gas exchange and biochemistry data did not exhibit clear differences between the groups. The spectral data were examined both daily and globally, utilizing the PARAFAC method applied to a three-way array of samples \u00d7 wavelengths \u00d7 days. The separation of the two plant groups was attributed to variations in water content (4v (O\u2212H)); shifts in the spectra red edge; and structural modifications in the epidermal layer and leaves\u2019 mesophyll. These spectral signatures can assist in the field identification of cork oaks that are interacting with P. cinnamomi.<\/jats:p>","DOI":"10.3390\/f14081663","type":"journal-article","created":{"date-parts":[[2023,8,17]],"date-time":"2023-08-17T10:15:48Z","timestamp":1692267348000},"page":"1663","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Spectral Analysis, Biocompounds, and Physiological Assessment of Cork Oak Leaves: Unveiling the Interaction with Phytophthora cinnamomi and Beyond"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8642-5792","authenticated-orcid":false,"given":"Rui","family":"Guerra","sequence":"first","affiliation":[{"name":"Departamento de F\u00edsica, Faculdade de Ci\u00eancias e Tecnologia, Universidade do Algarve, 8005-139 Faro, Portugal"},{"name":"Center for Electronic, Optoelectronic and Telecommunications (CEOT), Universidade do Algarve, 8005-139 Faro, Portugal"}]},{"given":"Rosa","family":"Pires","sequence":"additional","affiliation":[{"name":"Center for Electronic, Optoelectronic and Telecommunications (CEOT), Universidade do Algarve, 8005-139 Faro, Portugal"}]},{"given":"Ant\u00f3nio","family":"Br\u00e1zio","sequence":"additional","affiliation":[{"name":"Center for Electronic, Optoelectronic and Telecommunications (CEOT), Universidade do Algarve, 8005-139 Faro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2708-5991","authenticated-orcid":false,"given":"Ana Margarida","family":"Cavaco","sequence":"additional","affiliation":[{"name":"Center for Electronic, Optoelectronic and Telecommunications (CEOT), Universidade do Algarve, 8005-139 Faro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5081-3913","authenticated-orcid":false,"given":"Gabriela","family":"Sch\u00fctz","sequence":"additional","affiliation":[{"name":"Center for Electronic, Optoelectronic and Telecommunications (CEOT), Universidade do Algarve, 8005-139 Faro, Portugal"},{"name":"Instituto Superior de Engenharia, Universidade do Algarve, 8005-139 Faro, Portugal"}]},{"given":"Ana Cristina","family":"Coelho","sequence":"additional","affiliation":[{"name":"Center for Electronic, Optoelectronic and Telecommunications (CEOT), Universidade do Algarve, 8005-139 Faro, Portugal"},{"name":"Escola Superior de Educa\u00e7\u00e3o e Comunica\u00e7\u00e3o, Universidade do Algarve, 8005-139 Faro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,17]]},"reference":[{"key":"ref_1","unstructured":"(2015). 6.\u00b0 Invent\u00e1rio Florestal Nacional\u2014IFN6, Relat\u00f3rio Final, ICNF (Instituto da Conserva\u00e7\u00e3o da Natureza e das Florestas)."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1775","DOI":"10.1007\/s10021-021-00617-9","article-title":"Canopy Cover Loss of Mediterranean Oak Woodlands: Long-term Effects of Management and Climate","volume":"24","author":"Dias","year":"2021","journal-title":"Ecosystems"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"559","DOI":"10.1007\/s00704-023-04427-y","article-title":"Identification of forest vulnerability to droughts in the Iberian Peninsula","volume":"152","author":"Bento","year":"2023","journal-title":"Theor. 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