{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T10:20:49Z","timestamp":1776075649505,"version":"3.50.1"},"reference-count":43,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2016,11,26]],"date-time":"2016-11-26T00:00:00Z","timestamp":1480118400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Estimating leaf area index (LAI) of Vitis vinifera using indirect methods involves some critical issues, related to its discontinuous and non-homogeneous canopy. This study evaluates the smart app PocketLAI and hemispherical photography in vineyards against destructive LAI measurements. Data were collected during six surveys in an experimental site characterized by a high level of heterogeneity among plants, allowing us to explore a wide range of LAI values. During the last survey, the possibility to combine remote sensing data and in-situ PocketLAI estimates (smart scouting) was evaluated. Results showed a good agreement between PocketLAI data and direct measurements, especially for LAI ranging from 0.13 to 1.41 (R2 = 0.94, RRMSE = 17.27%), whereas the accuracy decreased when an outlying value (vineyard LAI = 2.84) was included (R2 = 0.77, RRMSE = 43.00%), due to the saturation effect in case of very dense canopies arising from lack of green pruning. The hemispherical photography showed very high values of R2, even in presence of the outlying value (R2 = 0.94), although it showed a marked and quite constant overestimation error (RRMSE = 99.46%), suggesting the need to introduce a correction factor specific for vineyards. During the smart scouting, PocketLAI showed its reliability to monitor the spatial-temporal variability of vine vigor in cordon-trained systems, and showed a potential for a wide range of applications, also in combination with remote sensing.<\/jats:p>","DOI":"10.3390\/s16122004","type":"journal-article","created":{"date-parts":[[2016,11,28]],"date-time":"2016-11-28T10:25:22Z","timestamp":1480328722000},"page":"2004","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["Estimating Leaf Area Index (LAI) in Vineyards Using the PocketLAI Smart-App"],"prefix":"10.3390","volume":"16","author":[{"given":"Francesca","family":"Orlando","sequence":"first","affiliation":[{"name":"Department of Agricultural and Environmental Sciences\u2014Production, Land, Agrienergy, Universit\u00e0 degli Studi di Milano, via Celoria 2, I-20133 Milan, Italy"},{"name":"Cassandra Lab, Universit\u00e0 degli Studi di Milano, via Celoria 2, I-20133 Milan, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ermes","family":"Movedi","sequence":"additional","affiliation":[{"name":"Department of Agricultural and Environmental Sciences\u2014Production, Land, Agrienergy, Universit\u00e0 degli Studi di Milano, via Celoria 2, I-20133 Milan, Italy"},{"name":"Cassandra Lab, Universit\u00e0 degli Studi di Milano, via Celoria 2, I-20133 Milan, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Davide","family":"Coduto","sequence":"additional","affiliation":[{"name":"Department of Agricultural and Environmental Sciences\u2014Production, Land, Agrienergy, Universit\u00e0 degli Studi di Milano, via Celoria 2, I-20133 Milan, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Simone","family":"Parisi","sequence":"additional","affiliation":[{"name":"Department of Agricultural and Environmental Sciences\u2014Production, Land, Agrienergy, Universit\u00e0 degli Studi di Milano, via Celoria 2, I-20133 Milan, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lucio","family":"Brancadoro","sequence":"additional","affiliation":[{"name":"Department of Agricultural and Environmental Sciences\u2014Production, Land, Agrienergy, Universit\u00e0 degli Studi di Milano, via Celoria 2, I-20133 Milan, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Valentina","family":"Pagani","sequence":"additional","affiliation":[{"name":"Cassandra Lab, Universit\u00e0 degli Studi di Milano, via Celoria 2, I-20133 Milan, Italy"},{"name":"Department of Economics, Management, and Quantitative Methods, Universit\u00e0 degli Studi di Milano, via Celoria 2, I-20133 Milan, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tommaso","family":"Guarneri","sequence":"additional","affiliation":[{"name":"Department of Agricultural and Environmental Sciences\u2014Production, Land, Agrienergy, Universit\u00e0 degli Studi di Milano, via Celoria 2, I-20133 Milan, Italy"},{"name":"Cassandra Lab, Universit\u00e0 degli Studi di Milano, via Celoria 2, I-20133 Milan, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Roberto","family":"Confalonieri","sequence":"additional","affiliation":[{"name":"Cassandra Lab, Universit\u00e0 degli Studi di Milano, via Celoria 2, I-20133 Milan, Italy"},{"name":"Department of Economics, Management, and Quantitative Methods, Universit\u00e0 degli Studi di Milano, via Celoria 2, I-20133 Milan, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2016,11,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1093\/oxfordjournals.aob.a083148","article-title":"Comparative physiological studies on the growth of field crops: I. Variation in net assimilation rate and leaf area between species and varieties, and within and between years","volume":"11","author":"Watson","year":"1947","journal-title":"Ann. Bot. Lond."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"219","DOI":"10.5344\/ajev.1995.46.2.219","article-title":"The light environment within grapevine canopies. II. Influence of leaf area density on fruit zone light environment and some canopy assessment","volume":"46","author":"Dokoozlian","year":"1995","journal-title":"Am. J. Enol. Vitic."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"10","DOI":"10.5344\/ajev.1958.9.1.10","article-title":"The relation of leaf area and climate to vine performance and grape quality","volume":"9","author":"Winkler","year":"1958","journal-title":"Am. J. Enol. Vitic."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"230","DOI":"10.5344\/ajev.1985.36.3.230","article-title":"Principles of grapevine canopy microclimate manipulation with implications for yield and quality. A review","volume":"36","author":"Smart","year":"1985","journal-title":"Am. J. Enol. Vitic."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"3125","DOI":"10.1080\/01431160903154382","article-title":"Very early prediction of wine yield based on satellite data from VEGETATION","volume":"31","author":"Cunha","year":"2010","journal-title":"Int. J. Remote Sens."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"201","DOI":"10.1016\/j.agrformet.2005.07.010","article-title":"Grapevine water use and the crop coefficient are linear functions of the shaded area measured beneath the canopy","volume":"132","author":"Williams","year":"2005","journal-title":"Agric. For. Meteorol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"395","DOI":"10.1094\/Phyto-79-395","article-title":"Microclimates of grapevine canopies associated with leaf removal and control of Botrytis bunch rot","volume":"79","author":"English","year":"1989","journal-title":"Phytopathology"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1287","DOI":"10.1016\/j.cropro.2006.11.003","article-title":"Variable rate application of plant protection products in vineyard using ultrasonic sensors","volume":"26","author":"Gil","year":"2007","journal-title":"Crop Prot."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"355","DOI":"10.1016\/j.compag.2010.12.015","article-title":"Support system for efficient dosage of orchard and vineyard spraying products","volume":"75","author":"Walklate","year":"2011","journal-title":"Comput. Electron. Agric."},{"key":"ref_10","first-page":"226","article-title":"Dosage des fongicides adapt\u00e9 \u00e0 la surface foliaire en viticulture: Efficacit\u00e9 de la lutte","volume":"42","author":"Viret","year":"2010","journal-title":"Rev. Suisse Vitic. Arboric. Hortic."},{"key":"ref_11","unstructured":"Pergher, G. (March, January 28). Metodi per adeguare la dose di agrofarmaco alle caratteristiche della chioma nei trattamenti alle colture arboree. Proceedings of the Problemi Sanitari Delle Colture Ortoflorovivaistiche ed Evoluzione Delle Strategie di Difesa, Turin, Italy. (In Italian)."},{"key":"ref_12","unstructured":"Pergher, G., and Petris, R. (2008). Pesticide Dose Adjustment in Vineyard Spraying and Potential for Dose Reduction. Agric. Eng. Int. CIGR J., X, Available online: https:\/\/cigrjournal.org\/index.php\/Ejounral\/article\/viewFile\/1254\/1111."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"73","DOI":"10.1016\/j.cropro.2006.04.002","article-title":"Dosage of plant protection products adapted to leaf area index in viticulture","volume":"26","author":"Siegfried","year":"2007","journal-title":"Crop Prot."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Campbell, G.S., and Norman, J.M. (1998). An Introduction to Environmental Biophysics, Springer. [2nd ed.].","DOI":"10.1007\/978-1-4612-1626-1"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1016\/j.agrformet.2003.08.001","article-title":"Review of methods for in situ leaf area index (LAI) determination Part II. Estimation of LAI, errors and sampling","volume":"121","author":"Weiss","year":"2004","journal-title":"Agric. For. Meteorol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"236","DOI":"10.21273\/HORTSCI.39.2.236","article-title":"Indirect measurement of Leaf Area Index in California North Coast vineyards","volume":"39","author":"Johnson","year":"2004","journal-title":"HortScience"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"116","DOI":"10.1111\/ajgw.12005","article-title":"Comparison of different protocols for indirect measurement of leaf area index with ceptometers in vertically trained vineyards","volume":"19","author":"Casterad","year":"2013","journal-title":"Aust. J. Grape Wine Res."},{"key":"ref_18","unstructured":"Bronge, B.L. (2004). Satellite Remote Sensing for Estimating Leaf Area Index, FPAR and Primary Production. A Literature Review, Swedish Nuclear Fuel and Waste Management Co.. No. SKB-R--04-24."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1016\/j.rse.2005.09.002","article-title":"Assessing vineyard condition with hyperspectral indices: Leaf and canopy reflectance simulation in a row-structured discontinuous canopy","volume":"99","author":"Miller","year":"2005","journal-title":"Remote Sens. Environ."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"465","DOI":"10.1111\/ajgw.12098","article-title":"Automated estimation of leaf area index from grapevine canopies using cover photography, video and computational analysis methods","volume":"20","author":"Fuentes","year":"2014","journal-title":"Aust. J. Grape Wine Res."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"36","DOI":"10.1111\/j.1755-0238.2002.tb00209.x","article-title":"Optical remote sensing applications in viticulture\u2014A review","volume":"8","author":"Hall","year":"2002","journal-title":"Aust. J. Grape Wine Res."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"226","DOI":"10.2134\/agronj2007.0167","article-title":"Nondestructive Measurement of Grapevine Leaf Area by Ground Normalized Difference Vegetation Index","volume":"101","author":"Drissi","year":"2009","journal-title":"Agron. J."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1016\/S0168-1699(02)00106-0","article-title":"Mapping vineyard leaf area with multispectral satellite imagery","volume":"38","author":"Johnson","year":"2003","journal-title":"Comput. Electron. Agric."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1111\/j.1755-0238.2002.tb00220.x","article-title":"Remote estimation of vine canopy density in vertically shoot-positioned vineyards: Determining optimal vegetation indices","volume":"8","author":"Dobrowski","year":"2002","journal-title":"Aust. J. Grape Wine Res."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1307","DOI":"10.1016\/j.agrformet.2009.03.001","article-title":"Optimal geometric configuration and algorithms for LAI indirect estimates under row canopies: The case of vineyards","volume":"149","author":"Baret","year":"2009","journal-title":"Agric. For. Meteorol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1016\/j.agrformet.2003.08.027","article-title":"Review of methods for in situ leaf area index determination. Part I. Theories, sensors and hemi-spherical photography","volume":"121","author":"Jonckheere","year":"2004","journal-title":"Agric. For. Meteorol."},{"key":"ref_27","first-page":"129","article-title":"Evaluation of digital and film hemispherical photography for predicting understorey light in a Bornean tropical rain forest","volume":"97","author":"Englund","year":"2000","journal-title":"Agric. For. Meteorol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"67","DOI":"10.1016\/j.compag.2013.04.019","article-title":"Development of an app for estimating leaf area index using a smartphone. Trueness and precision determination and comparison with other indirect methods","volume":"96","author":"Confalonieri","year":"2013","journal-title":"Comput. Electron. Agric."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1071\/BT9630095","article-title":"Estimation of foliage denseness and foliage angle by inclined point quadrats","volume":"11","year":"1963","journal-title":"Aust. J. Bot."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1393","DOI":"10.1016\/j.agrformet.2010.04.011","article-title":"GAI estimates of row crops from downward looking digital photos taken perpendicular to rows at 57.5 zenith angle: Theoretical considerations based on 3D architecture models and application to wheat crops","volume":"150","author":"Baret","year":"2010","journal-title":"Agric. For. Meteorol."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"38","DOI":"10.1016\/j.fcr.2013.09.024","article-title":"Comparison of leaf area index estimates by ceptometerand PocketLAI smart app in canopies with different structures","volume":"155","author":"Francone","year":"2014","journal-title":"Field Crop. Res."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"716","DOI":"10.1111\/avsc.12181","article-title":"Estimating leaf area index in tree species using the PocketLAI smart app","volume":"18","author":"Orlando","year":"2015","journal-title":"Appl. Veg. Sci."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"202","DOI":"10.3390\/rs8030202","article-title":"Multitemporal monitoring of plant area index in the Valencia rice district with PocketLAI","volume":"8","author":"Confalonieri","year":"2016","journal-title":"Remote Sens."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"De Bei, R., Fuentes, S., Gilliham, M., Tyerman, S., Edwards, E., Bianchini, N., Smith, J., and Collins, C. (2016). VitiCanopy: A free computer App to estimate canopy vigor and porosity for grapevine. Sensors, 16.","DOI":"10.3390\/s16040585"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"100","DOI":"10.1111\/j.1755-0238.1995.tb00085.x","article-title":"Growth Stages of the Grapevine: Phenological growth stages of the grapevine (Vitis vinifera L. ssp. vinifera)\u2014Codes and descriptions according to the extended BBCH scale","volume":"1","author":"Lorenz","year":"1995","journal-title":"Aust. J. Grape Wine Res."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"610","DOI":"10.1016\/j.scienta.2013.10.009","article-title":"Canopy leaf area index for apple tree using hemispherical photography in arid region","volume":"164","author":"Liu","year":"2013","journal-title":"Sci. Hortic."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"2403","DOI":"10.1093\/jxb\/erg263","article-title":"Ground-based measurements of leaf area index: A review of methods, instruments and current controversies","volume":"54","author":"Breda","year":"2003","journal-title":"J. Exp. Bot."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"165","DOI":"10.1016\/0304-3800(86)90024-4","article-title":"Validation of a prognosis based upon a eutrophication model","volume":"32","author":"Christensen","year":"1986","journal-title":"Ecol. Model."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"275","DOI":"10.1016\/0304-3800(80)90042-3","article-title":"A model evaluation methodology applicable to environmental assessment models","volume":"8","author":"Schaeffer","year":"1980","journal-title":"Ecol. Model."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"282","DOI":"10.1016\/0022-1694(70)90255-6","article-title":"River flow forecasting through conceptual models part I. A discussion of principles","volume":"10","author":"Nash","year":"1970","journal-title":"J. Hydrol."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"51","DOI":"10.1016\/0169-7722(91)90038-3","article-title":"Statistical and graphical methods for evaluating solute transport models: Overview and application","volume":"7","author":"Loague","year":"1991","journal-title":"J. Contam. Hydrol."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"96","DOI":"10.1016\/j.agrformet.2005.06.003","article-title":"Assessment of automatic gap fraction estimation of forests from digital hemispherical photography","volume":"132","author":"Jonckheere","year":"2005","journal-title":"Agric. For. Meteorol."},{"key":"ref_43","first-page":"3","article-title":"Canopy Management to Improve Grape Yield and Wine Quality Principles and Practices","volume":"11","author":"Smart","year":"1990","journal-title":"S. Afr. J. Enol. Vitic."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/16\/12\/2004\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T19:27:30Z","timestamp":1760210850000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/16\/12\/2004"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2016,11,26]]},"references-count":43,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2016,12]]}},"alternative-id":["s16122004"],"URL":"https:\/\/doi.org\/10.3390\/s16122004","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2016,11,26]]}}}