{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,11]],"date-time":"2026-04-11T02:51:57Z","timestamp":1775875917684,"version":"3.50.1"},"reference-count":81,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2022,12,21]],"date-time":"2022-12-21T00:00:00Z","timestamp":1671580800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100009620","name":"Agriculture, Forestry, and Fisheries Research Council","doi-asserted-by":"publisher","award":["19191026"],"award-info":[{"award-number":["19191026"]}],"id":[{"id":"10.13039\/100009620","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Tea is second only to water as the world\u2019s most popular drink and it is consumed in various forms, such as black and green teas. A range of cultivars has therefore been developed in response to customer preferences. In Japan, farmers may grow several cultivars to produce different types of tea. Leaf chlorophyll content is affected by disease, nutrition, and environmental factors. It also affects the color of the dried tea leaves: a higher chlorophyll content improves their appearance. The ability to quantify chlorophyll content would therefore facilitate improved tea tree management. Here, we measured the hyperspectral reflectance of 38 cultivars using a compact spectrometer. We also compared various combinations of preprocessing techniques and 14 variable selection methods. According to the ratio of performance to deviation (RPD), detrending was effective at reducing the influence of additive interference of scattered light from particles and then regression coefficients was the best variable selection method for estimating the chlorophyll content of tea leaves, achieving an RPD of 2.60 and a root mean square error of 3.21 \u03bcg cm\u22122.<\/jats:p>","DOI":"10.3390\/rs15010019","type":"journal-article","created":{"date-parts":[[2022,12,21]],"date-time":"2022-12-21T05:42:53Z","timestamp":1671601373000},"page":"19","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Applying Variable Selection Methods and Preprocessing Techniques to Hyperspectral Reflectance Data to Estimate Tea Cultivar Chlorophyll Content"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8330-3730","authenticated-orcid":false,"given":"Rei","family":"Sonobe","sequence":"first","affiliation":[{"name":"Faculty of Agriculture, Shizuoka University, Shizuoka 422-8529, Japan"},{"name":"Institute for Tea Science, Shizuoka University, Shizuoka 422-8529, Japan"}]},{"given":"Yuhei","family":"Hirono","sequence":"additional","affiliation":[{"name":"Institute for Tea Science, Shizuoka University, Shizuoka 422-8529, Japan"},{"name":"Institute of Fruit Tree and Tea Science, National Agriculture and Food Research Organization, Shimada 428-8501, Japan"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"389","DOI":"10.3136\/nskkk.57.389","article-title":"Identification of Tea Cultivar by Amolified DNA Fragment Length Polymorphism (AFLP) Using Black Teas as Sample","volume":"57","author":"Katoh","year":"2010","journal-title":"J. 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