{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,7]],"date-time":"2025-11-07T09:29:10Z","timestamp":1762507750969,"version":"build-2065373602"},"reference-count":45,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2019,6,20]],"date-time":"2019-06-20T00:00:00Z","timestamp":1560988800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"International Rice research Institute","award":["1"],"award-info":[{"award-number":["1"]}]},{"name":"International Rice Research Institute and Philippine Rice Research Institute","award":["1"],"award-info":[{"award-number":["1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The objective of this study is to provide complete information on the dynamic relationship between X-band (3.11 cm) backscattering intensity (\u03c3\u00b0) and rice crop\u2019s leaf area index (LAI) at all growth phases. Though the relationship between X-band \u03c3\u00b0 and LAI has been previously explored, details on the relationship at the reproductive phase remain unstudied. LAI at the reproductive phase is important particularly at the heading stage where LAI reaches its maximum as it is closely related to grain yield, and at flowering stage where the total leaf area affects the amount of photosynthates. Therefore, this study examined the relationship of increasing LAI (vegetative to reproductive phase) and decreasing LAI (ripening phase) with TerraSAR-X (TSX) ScanSAR (3.11 cm) \u03c3\u00b0 at HH polarisation and 45\u00b0 incidence angle. The results showed a statistically significant (R2 = 0.51, p value &lt; 0.001) non-linear relationship of LAI with \u03c3\u00b0 at the vegetative to reproductive phase while no significant linear relationship was found at the ripening phase. This study completes the response curve of X-band \u03c3\u00b0 to LAI by filling in the information on the reproductive phase which more accurately characterises the dynamic relationship between the rice crop\u2019s LAI and X-band\u2019s \u03c3\u00b0. This contributes to improved knowledge on the use of X-band data for estimating LAI for the whole crop cycle which is essential for the modelling of crop growth and estimation of yield.<\/jats:p>","DOI":"10.3390\/rs11121462","type":"journal-article","created":{"date-parts":[[2019,6,20]],"date-time":"2019-06-20T10:49:59Z","timestamp":1561027799000},"page":"1462","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Relating X-band SAR Backscattering to Leaf Area Index of Rice in Different Phenological Phases"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6966-3887","authenticated-orcid":false,"given":"Sonia","family":"Asilo","sequence":"first","affiliation":[{"name":"Faculty of Geo-Information Science and Earth Observation, University of Twente, 7500 AE Enschede, The Netherlands"},{"name":"Philippine Rice Research Institute, Science City of Munoz, Nueva Ecija 3119, Philippines"},{"name":"International Rice Research Institute, Los Ba\u00f1os, Laguna 4031, Philippines"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7249-3778","authenticated-orcid":false,"given":"Andrew","family":"Nelson","sequence":"additional","affiliation":[{"name":"Faculty of Geo-Information Science and Earth Observation, University of Twente, 7500 AE Enschede, The Netherlands"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3944-8924","authenticated-orcid":false,"given":"Kees","family":"de Bie","sequence":"additional","affiliation":[{"name":"Faculty of Geo-Information Science and Earth Observation, University of Twente, 7500 AE Enschede, The Netherlands"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7446-8429","authenticated-orcid":false,"given":"Andrew","family":"Skidmore","sequence":"additional","affiliation":[{"name":"Faculty of Geo-Information Science and Earth Observation, University of Twente, 7500 AE Enschede, The Netherlands"},{"name":"Macquarie University, Sydney, NSW 2109, Australia"}]},{"given":"Alice","family":"Laborte","sequence":"additional","affiliation":[{"name":"International Rice Research Institute, Los Ba\u00f1os, Laguna 4031, Philippines"}]},{"given":"Aileen","family":"Maunahan","sequence":"additional","affiliation":[{"name":"International Rice Research Institute, Los Ba\u00f1os, Laguna 4031, Philippines"}]},{"given":"Eduardo Jimmy P.","family":"Quilang","sequence":"additional","affiliation":[{"name":"Philippine Rice Research Institute, Science City of Munoz, Nueva Ecija 3119, Philippines"}]}],"member":"1968","published-online":{"date-parts":[[2019,6,20]]},"reference":[{"key":"ref_1","unstructured":"(2018, December 12). 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