{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:55:08Z","timestamp":1760151308567,"version":"build-2065373602"},"reference-count":25,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2022,3,15]],"date-time":"2022-03-15T00:00:00Z","timestamp":1647302400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001700","name":"Ministry of Education, Culture, Sports, Science and Technology","doi-asserted-by":"publisher","award":["Program for Building Regional Innovation Ecosystems"],"award-info":[{"award-number":["Program for Building Regional Innovation Ecosystems"]}],"id":[{"id":"10.13039\/501100001700","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Approximately half of the world\u2019s apple production occurs in East Asia, where apple Valsa canker (AVC) is a prominent disease. This disease affects the bark of the tree, ultimately killing it and resulting in significant economic loss. Visual identification of the diseased area of the bark, particularly in the early stages, is extremely difficult. In this study, we conducted hyperspectral imaging of the trunks and branches of AVC-infected apple trees and revealed that the diseased area can be identified in the near-infrared reflectance, even when it is difficult to distinguish visually. A discriminant analysis using the Mahalanobis distance was performed on the normalized difference spectral index (NDSI) obtained from the measured spectral reflectance. A diagnostic model for discriminating between the healthy and diseased areas was created using the threshold value of NDSI. An accuracy assessment of the diagnostic model presented the overall accuracy as &gt;0.94 for the combinations of spectral bands at 660\u2013690 nm and 720\u2013760 nm. This simple diagnostic model can be applied to other tree bark canker diseases.<\/jats:p>","DOI":"10.3390\/rs14061420","type":"journal-article","created":{"date-parts":[[2022,3,16]],"date-time":"2022-03-16T03:36:23Z","timestamp":1647401783000},"page":"1420","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Detection of Apple Valsa Canker Based on Hyperspectral Imaging"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3896-7252","authenticated-orcid":false,"given":"Junichi","family":"Kurihara","sequence":"first","affiliation":[{"name":"Faculty of Science, Hokkaido University, Sapporo 001-0021, Japan"}]},{"given":"Toshikazu","family":"Yamana","sequence":"additional","affiliation":[{"name":"Central Agricultural Experiment Station, Agricultural Research Department, Hokkaido Research Organization, Naganuma 069-1395, Japan"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,15]]},"reference":[{"key":"ref_1","first-page":"1","article-title":"Taxonomic Studies of Japanese Diaporthaceae with Special Reference to Their Life-Histories","volume":"Volume 226","author":"Kobayashi","year":"1970","journal-title":"Bulletin of the Government Forest Experiment Station"},{"key":"ref_2","unstructured":"(2022, January 17). 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