{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T16:18:54Z","timestamp":1776442734131,"version":"3.51.2"},"reference-count":37,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2014,10,9]],"date-time":"2014-10-09T00:00:00Z","timestamp":1412812800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003141","name":"Consejo Nacional de Ciencia y Tecnolog\u00eda","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100003141","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Soil drought represents one of the most dangerous stresses for plants. It impacts the yield and quality of crops, and if it remains undetected for a long time, the entire crop could be lost. However, for some plants a certain amount of drought stress improves specific characteristics. In such cases, a device capable of detecting and quantifying the impact of drought stress in plants is desirable. This article focuses on testing if the monitoring of physiological process through a gas exchange methodology provides enough information to detect drought stress conditions in plants. The experiment consists of using a set of smart sensors based on Field Programmable Gate Arrays (FPGAs) to monitor a group of plants under controlled drought conditions. The main objective was to use different digital signal processing techniques such as the Discrete Wavelet Transform (DWT) to explore the response of plant physiological processes to drought. Also, an  index-based methodology was utilized to compensate the spatial variation inside the greenhouse. As a result, differences between treatments were determined to be independent of climate variations inside the greenhouse. Finally, after using the DWT as digital filter, results demonstrated that the proposed system is capable to reject high frequency noise and to detect drought conditions.<\/jats:p>","DOI":"10.3390\/s141018650","type":"journal-article","created":{"date-parts":[[2014,10,9]],"date-time":"2014-10-09T10:20:20Z","timestamp":1412850020000},"page":"18650-18669","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["FPGA-Based Smart Sensor for Drought Stress Detection in Tomato Plants Using Novel Physiological Variables and Discrete Wavelet Transform"],"prefix":"10.3390","volume":"14","author":[{"given":"Carlos","family":"Duarte-Galvan","sequence":"first","affiliation":[{"name":"CA Ingenier\u00eda de Biosistemas, Divisi\u00f3n de Investigaci\u00f3n y Posgrado, Facultad de Ingenier\u00eda, Universidad Aut\u00f3noma de Quer\u00e9taro, Cerro de las Campanas s\/n, Quer\u00e9taro 76010, Qro., Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3192-5332","authenticated-orcid":false,"given":"Rene","family":"Romero-Troncoso","sequence":"additional","affiliation":[{"name":"HSPdigital-CA Telem\u00e1tica, DICIS, Universidad de Guanajuato, Carr. Salamanca-Valle km 3.5+1.8, Palo Blanco, Salamanca 36885, Gto, Mexico"}]},{"given":"Irineo","family":"Torres-Pacheco","sequence":"additional","affiliation":[{"name":"CA Ingenier\u00eda de Biosistemas, Divisi\u00f3n de Investigaci\u00f3n y Posgrado, Facultad de Ingenier\u00eda, Universidad Aut\u00f3noma de Quer\u00e9taro, Cerro de las Campanas s\/n, Quer\u00e9taro 76010, Qro., Mexico"}]},{"given":"Ramon","family":"Guevara-Gonzalez","sequence":"additional","affiliation":[{"name":"CA Ingenier\u00eda de Biosistemas, Divisi\u00f3n de Investigaci\u00f3n y Posgrado, Facultad de Ingenier\u00eda, Universidad Aut\u00f3noma de Quer\u00e9taro, Cerro de las Campanas s\/n, Quer\u00e9taro 76010, Qro., Mexico"}]},{"given":"Arturo","family":"Fernandez-Jaramillo","sequence":"additional","affiliation":[{"name":"CA Ingenier\u00eda de Biosistemas, Divisi\u00f3n de Investigaci\u00f3n y Posgrado, Facultad de Ingenier\u00eda, Universidad Aut\u00f3noma de Quer\u00e9taro, Cerro de las Campanas s\/n, Quer\u00e9taro 76010, Qro., Mexico"}]},{"given":"Luis","family":"Contreras-Medina","sequence":"additional","affiliation":[{"name":"CA Ingenier\u00eda de Biosistemas, Divisi\u00f3n de Investigaci\u00f3n y Posgrado, Facultad de Ingenier\u00eda, Universidad Aut\u00f3noma de Quer\u00e9taro, Cerro de las Campanas s\/n, Quer\u00e9taro 76010, Qro., Mexico"},{"name":"HSPdigital-CA Telem\u00e1tica, DICIS, Universidad de Guanajuato, Carr. Salamanca-Valle km 3.5+1.8, Palo Blanco, Salamanca 36885, Gto, Mexico"}]},{"given":"Roberto","family":"Carrillo-Serrano","sequence":"additional","affiliation":[{"name":"Divisi\u00f3n de Investigaci\u00f3n y Posgrado, Facultad de Ingenier\u00eda, Universidad Aut\u00f3noma de Quer\u00e9taro, Cerro de las Campanas s\/n, Quer\u00e9taro 76010, Qro., Mexico"}]},{"given":"Jesus","family":"Millan-Almaraz","sequence":"additional","affiliation":[{"name":"Facultad de Ciencias F\u00edsico-Matem\u00e1ticas, Universidad Aut\u00f3noma de Sinaloa, Av. De las Am\u00e9ricas y Blvd. Universitario, Cd. Universitaria, Culiac\u00e1n 80000, Sinaloa, Mexico"}]}],"member":"1968","published-online":{"date-parts":[[2014,10,9]]},"reference":[{"key":"ref_1","unstructured":"Taiz, L., and Zeiger, E. (2010). Plants Physiology, Sinauer Associates Incorporated."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Aroca, R. (2012). Plant Responses to Drought Stress: From Morphological to Molecular Features, Springer.","DOI":"10.1007\/978-3-642-32653-0"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"4203","DOI":"10.3390\/ijms14024203","article-title":"Agriculture and bioactives: Achieving both crop yield and phytochemicals","volume":"14","year":"2013","journal-title":"Int. J. Mol. Sci."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"11853","DOI":"10.3390\/s120911853","article-title":"Instrumentation in developing chlorophyll fluorescence biosensing: A review","volume":"12","year":"2012","journal-title":"Sensors"},{"key":"ref_5","first-page":"79","article-title":"An insight to the performance of crop water stress index for olive trees","volume":"118","author":"Agam","year":"2013","journal-title":"Agric. WaterManag."},{"key":"ref_6","unstructured":"Udompetaikul, V., Upadhyaya, S.K., Slaughter, D., Lampinen, B., Shackel, K., and House, G. (2011, January 7\u201310). Plant Water Stress Detection Using Leaf Temperature and Microclimatic Information. Louisville, KY, USA."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1497","DOI":"10.1016\/j.agwat.2011.05.002","article-title":"Development and validation of an automatic thermal imaging process for assessing plant water status","volume":"98","author":"Ballester","year":"2011","journal-title":"Agric. Water Manag."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"3530","DOI":"10.3390\/s130303530","article-title":"Deployment of a fully-automated green fluorescent protein imaging system in a high arctic autonomous greenhouse","volume":"13","author":"Abboud","year":"2013","journal-title":"Sensors"},{"key":"ref_9","first-page":"7340","article-title":"Advantages and disadvantages on photosynthesis measurement techniques: A review","volume":"8","year":"2009","journal-title":"Afr. J. Biotechnol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1016\/j.compag.2010.03.005","article-title":"Evaluation of plant seedling water stress using dynamic fluorescence index with blue led-based fluorescence imaging","volume":"72","author":"Hsiao","year":"2010","journal-title":"Comput. Electron. Agric."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1016\/j.compag.2011.04.008","article-title":"Hyperspectral image analysis for water stress detection of apple trees","volume":"77","author":"Kim","year":"2011","journal-title":"Comput. Electron. Agric."},{"key":"ref_12","first-page":"1","article-title":"Comparative analysis of different uni- and multi-variate methods for estimation of vegetation water content using hyper-spectral measurements","volume":"26","author":"Mirzaie","year":"2014","journal-title":"Int. J. Appl. Earth Obs. Geoinf."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"979","DOI":"10.3390\/s7060979","article-title":"A coupled remote sensing and simplified surface energy balance approach to estimate actual evapotranspiration from irrigated fields","volume":"7","author":"Senay","year":"2007","journal-title":"Sensors"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1679","DOI":"10.1016\/j.agrformet.2008.05.020","article-title":"Estimating crop water stress with ETM + NIR and SWIR data","volume":"148","author":"Ghulam","year":"2008","journal-title":"Agric. Forest Meteorol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1","DOI":"10.3390\/s90100001","article-title":"A one-layer satellite surface energy balance for estimating evapotranspiration rates and crop water stress indexes","volume":"9","author":"Barbagallo","year":"2009","journal-title":"Sensors"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"286","DOI":"10.1016\/j.rse.2009.09.006","article-title":"Detecting water stress effects on fruit quality in orchards with time-series PRI airborne imagery","volume":"114","author":"Berni","year":"2010","journal-title":"Remote Sens. Environ."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"67","DOI":"10.1016\/j.sna.2012.06.021","article-title":"A leaf-mounted thermal sensor for the measurement of water content","volume":"187","author":"Atherton","year":"2012","journal-title":"Sens. Actuators A Phys."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.biosystemseng.2009.01.013","article-title":"Monitoring system for electrical signals in plants in the greenhouse and its applications","volume":"103","author":"Wang","year":"2009","journal-title":"Biosyst. Eng."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"370","DOI":"10.1007\/s11119-011-9252-3","article-title":"A plant based sensing method for nutrition stress monitoring","volume":"13","author":"Tomkiewicz","year":"2012","journal-title":"Precis. Agric."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"7814","DOI":"10.3390\/s91007814","article-title":"Investigation of SOI raman lasers for mid-infrared gas sensing","volume":"9","author":"Passaro","year":"2009","journal-title":"Sensors"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"50","DOI":"10.1016\/j.agwat.2012.11.018","article-title":"Responses of leaf night transpiration to drought stress in Vitis vinifera L","volume":"118","author":"Escalona","year":"2013","journal-title":"Agric. Water Manag."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"58","DOI":"10.1016\/j.compag.2013.04.009","article-title":"FPGA-based wireless smart sensor for real-time photosynthesis monitoring","volume":"95","year":"2013","journal-title":"Comput. Electron. Agric."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"249","DOI":"10.17660\/ActaHortic.1998.421.26","article-title":"Low-cost system for on-line measurement of plant transpiration and photosynthesis in greenhouse production","volume":"421","author":"Schmidt","year":"1998","journal-title":"Acta Hortic."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"15244","DOI":"10.3390\/s121115244","article-title":"Virtual sensors for designing irrigation controllers in greenhouses","volume":"12","author":"Arahal","year":"2012","journal-title":"Sensors"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"8316","DOI":"10.3390\/s100908316","article-title":"FPGA-based fused smart sensor for real-time plant-transpiration dynamic estimation","volume":"10","year":"2010","journal-title":"Sensors"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"275","DOI":"10.1093\/treephys\/tpq112","article-title":"Different sensitivity of isoprene emission, respiration and photosynthesis to high growth temperature coupled with drought stress in black poplar (populus nigra) saplings","volume":"31","author":"Centritto","year":"2011","journal-title":"Tree Physiol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"427","DOI":"10.1111\/j.1365-313X.2006.02879.x","article-title":"Tobacco aquaporin NtAQP1 is involved in mesophyll conductance to CO2 in vivo","volume":"48","author":"Flexas","year":"2006","journal-title":"Plant J."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1431","DOI":"10.1078\/0176-1617-00578","article-title":"Diterpenes and antioxidative protection in drought-stressed Salvia officinalis plants","volume":"158","author":"Mueller","year":"2001","journal-title":"J. Plant Physiol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"608","DOI":"10.1007\/s004250100646","article-title":"Plant aging increases oxidative stress in chloroplasts","volume":"214","author":"Alegre","year":"2002","journal-title":"Planta"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1046\/j.1365-3040.2001.00660.x","article-title":"Stomatal conductance and photosynthesis vary linearly with plant hydraulic conductance in ponderosa pine","volume":"24","author":"Hubbard","year":"2001","journal-title":"Plant Cell Environ."},{"key":"ref_31","unstructured":"(2008). Hand-Held Photosynthesis System Instruction Manual, CID Inc."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"4335","DOI":"10.3390\/s110404335","article-title":"Fused smart sensor network for multi-axis forward kinematics estimation in industrial robots","volume":"11","year":"2011","journal-title":"Sensors"},{"key":"ref_33","unstructured":"Ton, Y., and Kopyt, M. (, January October). Phytomonitoring information and decision-support system for crop growing. Beijing, China."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"995","DOI":"10.7326\/0003-4819-130-12-199906150-00008","article-title":"Toward evidence-based medical statistics. 1: The p value fallacy","volume":"130","author":"Goodman","year":"1999","journal-title":"Ann. Intern. Med."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1016\/j.biosystemseng.2012.05.003","article-title":"Estimating the response of tomato (solanum lycopersicum) leaf area to changes in climate and salicylic acid applications by means of artificial neural networks","volume":"112","year":"2012","journal-title":"Biosyst. Eng."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Sharma, P., Jha, A.B., Dubey, R.S., and Pessarakli, M. (2012). Reactive oxygen species, oxidative damage, and antioxidative defense mechanism in plants under stressful conditions. J. Bot., 2012.","DOI":"10.1155\/2012\/217037"},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Beebe, S.E., Rao, I.M., Blair, M.W., and Acosta-Gallegos, J.A. (2013). Phenotyping common beans for adaptation to drought. Front. Physiol., 4.","DOI":"10.3389\/fphys.2013.00035"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/14\/10\/18650\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:16:43Z","timestamp":1760217403000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/14\/10\/18650"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2014,10,9]]},"references-count":37,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2014,10]]}},"alternative-id":["s141018650"],"URL":"https:\/\/doi.org\/10.3390\/s141018650","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2014,10,9]]}}}