{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T22:50:18Z","timestamp":1770677418808,"version":"3.49.0"},"reference-count":62,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2023,9,17]],"date-time":"2023-09-17T00:00:00Z","timestamp":1694908800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Potatoes South Africa"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Estimating crop coefficients and evapotranspiration (ET) accurately is crucial for optimizing irrigation. Remote sensing techniques using green canopy cover, leaf area index (LAI), and normalized difference vegetation index (NDVI) have been applied to estimate basal crop coefficients (Kcb) and ET for different crops. However, analysis of the potential of these techniques to improve water management in irrigated potato (Solanum tuberosum L.) is still lacking. This study aimed to assess the modified nonlinear relationship between LAI, Kcb and NDVI in estimating crop coefficients (Kc) and ET of potato. Moreover, Kc and ET were derived from the measured fraction of green canopy cover (FGCC) and the FAO-56 approach. ET estimated from the FAO-56, FGCC and NDVI approaches were compared with the ET simulated using the LINTUL-Potato model. The results showed that the Kc values based on FGCC and NDVI were on average 0.16 lower than values based on FAO-56 Kc during the mid-season growing stage. ET estimated from FAO-56, FGCC and NDVI compared well with ET calculated by the LINTUL-Potato model, with RMSE values of 0.83, 0.79, and 0.78 mm day\u22121, respectively. These results indicate that dynamic crop coefficients and potato ET can be estimated from canopy cover and NDVI. The outcomes of this study will assist potato growers in determining crop water requirements using real-time ETo, canopy state variables and NDVI data from satellite images.<\/jats:p>","DOI":"10.3390\/rs15184579","type":"journal-article","created":{"date-parts":[[2023,9,17]],"date-time":"2023-09-17T23:32:27Z","timestamp":1694993547000},"page":"4579","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Determination of Crop Coefficients and Evapotranspiration of Potato in a Semi-Arid Climate Using Canopy State Variables and Satellite-Based NDVI"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3456-6905","authenticated-orcid":false,"given":"Alex","family":"Mukiibi","sequence":"first","affiliation":[{"name":"Department of Plant and Soil Sciences, University of Pretoria, Hatfield 0028, South Africa"}]},{"given":"Angelinus Cornelius","family":"Franke","sequence":"additional","affiliation":[{"name":"Department of Soil, Crop and Climate Sciences, University of the Free State, Bloemfontein 9300, South Africa"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9959-3234","authenticated-orcid":false,"given":"Joachim Martin","family":"Steyn","sequence":"additional","affiliation":[{"name":"Department of Plant and Soil Sciences, University of Pretoria, Hatfield 0028, South Africa"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,17]]},"reference":[{"key":"ref_1","unstructured":"Stevens, J., Sanewe, A., Steyn, J.M., Annandale, J.G., and Stirzaker, R.J. (2020). Improving On-Farm Irrigation Water and Solute Management Using Simple Tools and Adaptive Learning, Water Research Commission. Report No. TT821\/20."},{"key":"ref_2","unstructured":"Basson, M.S. (2011, January 3\u20135). Water development in South Africa. Proceedings of the Water in the Green Economy in Practice: Towards Rio+20, Zaragoza, Spain."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"297","DOI":"10.1016\/j.agsy.2010.12.001","article-title":"Developing environmental principles, criteria, indicators and norms for potato production in South Africa through field surveys and modelling","volume":"104","author":"Franke","year":"2011","journal-title":"Agric. Syst."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"136","DOI":"10.1016\/j.fcr.2016.09.020","article-title":"Resource use efficiencies as indicators of ecological sustainability in potato production: A South African case study","volume":"199","author":"Steyn","year":"2016","journal-title":"Field Crops Res."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"195","DOI":"10.1007\/s11540-016-9321-0","article-title":"Forecasting yield and tuber size of processing potatoes in South Africa using the LINTUL-Potato-DSS Model","volume":"59","author":"Machakaire","year":"2016","journal-title":"Potato Res."},{"key":"ref_6","unstructured":"Charlesworth, P. (2000). Soil Water and Ground Water Sampling, CSIRO Land and Water."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"751","DOI":"10.4314\/wsa.v37i5.12","article-title":"Irrigation scheduling research: South African experiences and future prospects","volume":"37","author":"Annandale","year":"2011","journal-title":"Water SA"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"899","DOI":"10.1016\/j.agwat.2010.12.015","article-title":"Evapotranspiration information reporting: I. Factors governing measurement accuracy","volume":"98","author":"Allen","year":"2011","journal-title":"Agric. Water Manag."},{"key":"ref_9","first-page":"103","article-title":"Atmospheric evaporative demand and evaporation coefficient concepts","volume":"15","year":"1989","journal-title":"Water SA"},{"key":"ref_10","unstructured":"Allen, R.G., Pereira, L.S., Raes, D., and Smith, M. (1998). Crop Evapotranspiration (Guidelines for Computing Crop Water Requirements. FAO Irrigation and Drainage Paper No.56, FAO."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"106081","DOI":"10.1016\/j.agwat.2020.106081","article-title":"Remote sensing for estimating and mapping single and basal crop coefficients: A review on spectral vegetation indices approaches","volume":"233","author":"Calera","year":"2020","journal-title":"Agric. Water Manag."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1016\/j.agwat.2012.11.005","article-title":"Monitoring evapotranspiration of irrigated crops using crop coefficients derived from time series of satellite images. I. Method validation","volume":"125","author":"Mateos","year":"2013","journal-title":"Agric. Water Manag."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1007\/s10795-005-5195-z","article-title":"Irrigation water management using high resolution airborne remote sensing","volume":"19","author":"Neale","year":"2005","journal-title":"Irrig. Drain. Syst."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"213","DOI":"10.1016\/0034-4257(93)90096-G","article-title":"Soil background effects on reflectance-based crop coefficients for corn","volume":"46","author":"Bausch","year":"1993","journal-title":"Remote Sens. Environ."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"48","DOI":"10.1016\/j.agwat.2007.09.001","article-title":"Spectral vegetation indices for benchmarking water productivity of irrigated cotton and sugarbeet crops","volume":"95","author":"Mateos","year":"2008","journal-title":"Agric. Water Manag."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.agwat.2005.02.013","article-title":"Monitoring wheat phenology and irrigation in Central Morocco: On the use of relationships between evapotranspiration, crops coefficients, leaf area index and remotely-sensed vegetation indices","volume":"79","author":"Duchemin","year":"2006","journal-title":"Agric. Water Manag."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/0034-4257(94)90090-6","article-title":"Relations between evaporation coefficients and vegetation indices studied by model simulations","volume":"50","author":"Choudhury","year":"1994","journal-title":"Remote Sens. Environ."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"4050","DOI":"10.1002\/hyp.8392","article-title":"Vegetation index-based crop coefficients to estimate evapotranspiration by remote sensing in agricultural and natural ecosystems","volume":"25","author":"Glenn","year":"2011","journal-title":"Hydrol. Process."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/s00271-005-0001-0","article-title":"Wheat basal crop coefficients determined by normalized difference vegetation index","volume":"24","author":"Hunsaker","year":"2005","journal-title":"Irrig. Sci."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1016\/j.agwat.2018.02.022","article-title":"Evaluation of variable rate irrigation using a remote-sensing-based model","volume":"203","author":"Barker","year":"2018","journal-title":"Agric. Water Manag."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"235","DOI":"10.1016\/j.agwat.2006.10.020","article-title":"Development and validation of canopy reflectance-based crop coefficient for potato","volume":"88","author":"Jayanthi","year":"2007","journal-title":"Agric. Water Manag."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1016\/j.agwat.2013.02.007","article-title":"Determination of crop evapotranspiration of table grapes in a semi-arid region of Northwest Mexico using multi-spectral vegetation index","volume":"122","author":"Rodriguez","year":"2013","journal-title":"Agric. Water Manag."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1016\/j.agwat.2017.04.017","article-title":"Validation of two Huanjing-1A\/B satellite-based FAO-56 models for estimating winter wheat crop evapotranspiration during mid-season","volume":"189","author":"Jin","year":"2017","journal-title":"Agric. Water Manag."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"140","DOI":"10.1016\/j.agwat.2017.03.022","article-title":"Reflectance-based crop coefficients REDUX: For operational evapotranspiration estimates in the age of high producing hybrid varieties","volume":"187","author":"Campos","year":"2017","journal-title":"Agric. Water Manag."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"775","DOI":"10.4314\/wsa.v38i5.17","article-title":"Rainy season characteristics of the Free State Province of South Africa with reference to rain-fed maize production","volume":"38","author":"Moeletsi","year":"2012","journal-title":"Water SA"},{"key":"ref_26","unstructured":"Kruger, A.C., and Mbatha, S. (2021). Regional Weather and Climate of South Africa: Gauteng."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Haverkort, A.J., and MacKerron, D.K.L. (1995). Potato Ecology and Modelling of Crops under Conditions Limiting Growth, Kluwer Academic Publishers. [1st ed.].","DOI":"10.1007\/978-94-011-0051-9"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1080\/15427528.2011.538465","article-title":"Improving nutrient-use efficiency in chinese potato production: Experiences from the United States","volume":"25","author":"Alva","year":"2011","journal-title":"J. Crop Improv."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"333","DOI":"10.1007\/s11540-008-9120-3","article-title":"Physiology of the potato: New insights into root system and repercussions for crop management","volume":"51","author":"Iwama","year":"2008","journal-title":"Potato Res."},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Djaman, K., Koudahe, K., Saibou, A., Darapuneni, M., Higgins, C., and Irmak, S. (2022). Soil water dynamics, effective rooting zone, and evapotranspiration of sprinkler irrigated potato in a sandy loam soil. Agronomy, 12.","DOI":"10.3390\/agronomy12040864"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"2312","DOI":"10.2134\/agronj15.0150","article-title":"Canopeo: A powerful new tool for measuring fractional green canopy cover","volume":"107","author":"Patrignani","year":"2015","journal-title":"Agron. J."},{"key":"ref_32","unstructured":"Haverkort, A.J. (2018). Potato Handbook: Crop of the Future, Aardappelwereld BV."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"375","DOI":"10.3390\/rs2010375","article-title":"Combining satellite remote sensing data with the FAO-56 dual approach for water use mapping in irrigated wheat fields of a semi-arid region","volume":"2","author":"Chehbouni","year":"2010","journal-title":"Remote Sens."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"51","DOI":"10.1007\/s11540-013-9229-x","article-title":"Climate change and potato production in contrasting South African agro-ecosystems 2. Assessing risks and opportunities of adaptation strategies","volume":"56","author":"Franke","year":"2013","journal-title":"Potato Res."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1007\/s11540-015-9303-7","article-title":"A robust potato model: LINTUL-POTATO-DSS","volume":"58","author":"Haverkort","year":"2015","journal-title":"Potato Res."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Prasad, R., Hochmuth, G.J., and Boote, K.J. (2015). Estimation of nitrogen pools in irrigated potato production on sandy soil using the model SUBSTOR. PLoS ONE, 1.","DOI":"10.1371\/journal.pone.0117891"},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Cl\u00e9ment, C.C., Cambouris, A.N., Ziadi, N., Zebarth, B.J., and Karam, A. (2021). Potato yield response and seasonal nitrate leaching as influenced by nitrogen management. Agronomy, 11.","DOI":"10.3390\/agronomy11102055"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"2090","DOI":"10.3390\/rs15082090","article-title":"Crop phenology modelling using proximal and satellite sensor data","volume":"15","author":"Gobin","year":"2023","journal-title":"Remote Sens."},{"key":"ref_39","first-page":"1785","article-title":"Hourly and daily single and basal evapotranspiration crop coefficients as a function of growing degree days, days after emergence, leaf area index, fractional green canopy cover, and plant phenology for soybean","volume":"56","author":"Irmak","year":"2013","journal-title":"Trans. ASABE"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"2491","DOI":"10.1080\/01431160802552744","article-title":"Correlation between potato yield and MODIS-derived vegetation indices","volume":"30","author":"Bala","year":"2009","journal-title":"Int. J. Remote Sens."},{"key":"ref_41","first-page":"65","article-title":"A comprehensive assessment of the correlations between field crop yields and commonly used MODIS products","volume":"52","author":"Johnson","year":"2016","journal-title":"Int. J. Appl. Earth Obs. Geoinf."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1007\/s41976-018-0006-0","article-title":"Yield prediction model for potato using Landsat time series images driven vegetation indices","volume":"1","author":"Newton","year":"2018","journal-title":"Remote Sens. Earth Syst. Sci."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"106196","DOI":"10.1016\/j.agwat.2020.106196","article-title":"Standard single and basal crop coefficients for vegetable crops, an update of FAO56 crop water requirements approach","volume":"243","author":"Pereira","year":"2021","journal-title":"Agric. Water Manag."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"57","DOI":"10.1061\/JRCEA4.0001372","article-title":"New evapotranspiration crop coefficients","volume":"108","author":"Wright","year":"1982","journal-title":"J. Irrig. Drain. Div."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1016\/j.agwat.2010.07.011","article-title":"Assessing satellite-based basal crop coefficients for irrigated grapes (Vitis vinifera L.)","volume":"98","author":"Campos","year":"2010","journal-title":"Agric. Water Manag."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"2373","DOI":"10.3390\/rs70302373","article-title":"Estimation of actual crop coefficients using remotely sensed vegetation indices and soil water balance modelled data","volume":"7","author":"Paredes","year":"2015","journal-title":"Remote Sens."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"107029","DOI":"10.1016\/j.agwat.2021.107029","article-title":"Assessing evapotranspiration and crop coefficients of potato in a semi-arid climate using Eddy Covariance techniques","volume":"255","author":"Machakaire","year":"2021","journal-title":"Agric. Water Manag."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"439","DOI":"10.3390\/rs4020439","article-title":"Satellite NDVI assisted monitoring of vegetable crop evapotranspiration in california\u2019s san Joaquin Valley","volume":"4","author":"Johnson","year":"2012","journal-title":"Remote Sens."},{"key":"ref_49","unstructured":"Denner, F.D., Venter, S., and Niederwieser, J. (2012). Guide to Potato Production in South Africa, ARC-Roodeplaat, Vegetable and Ornamental Plants Institute. [1st ed.]."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"421","DOI":"10.1007\/s11540-020-09484-8","article-title":"Crop coefficient for potato crop evapotranspiration estimation by field water balance method in semi-arid region, Maharashtra, India","volume":"64","author":"Kadam","year":"2021","journal-title":"Potato Res."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"108371","DOI":"10.1016\/j.agwat.2023.108371","article-title":"Evaluating potato evapotranspiration and crop coefficients in the Columbia Basin of Washington state","volume":"286","author":"Gonzalez","year":"2023","journal-title":"Agric. Water Manag."},{"key":"ref_52","unstructured":"Unites States Bureau of Reclaimation (USBR) (2023, July 28). Agrinet Crop Coefficients: Potatoes, Available online: https:\/\/www.usbr.gov\/pn\/agrimet\/cropcurves\/POTAcc.html."},{"key":"ref_53","doi-asserted-by":"crossref","unstructured":"Chakroun, H., Zemni, N., Benhamid, A., Dellaly, V., Slama, F., Bouksila, F., and Berndtsson, R. (2023). Evapotranspiration in semi-arid climate:Remote sensing vs. soil water simulation. Sensors, 23.","DOI":"10.3390\/s23052823"},{"key":"ref_54","unstructured":"Steyn, J.M., Kagabo, D.M., and Annandale, J.G. (2007, January 27\u201331). Potato growth and yield responses to irrigation regimes in contrasting seasons of a subtropical region. Proceedings of the 8th African Crop Science Society Conference, El-Minia, Egypt."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1016\/j.agwat.2018.01.008","article-title":"Potato growth, yield and water productivity response to different irrigation and fertilization regimes","volume":"201","author":"Ierna","year":"2018","journal-title":"Agric. Water Manag."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"284","DOI":"10.3923\/ja.2006.284.288","article-title":"The effect of deficit irrigation on potato evapotranspiration and tuber yield under cool season and semi-arid climatic conditions","volume":"5","author":"Kiziloglu","year":"2006","journal-title":"J. Agron."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"106266","DOI":"10.1016\/j.agwat.2020.106266","article-title":"Satellite-based NDVI crop coefficients and evapotranspiration with eddy covariance validation for multiple durum wheat fields in the US Southwest","volume":"239","author":"French","year":"2020","journal-title":"Agric. Water Manag."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"1395","DOI":"10.13031\/2013.19197","article-title":"Cotton irrigation scheduling using remotely sensed and FAO-56 basal crop coefficients","volume":"48","author":"Hunsaker","year":"2005","journal-title":"Trans. Am. Soc. Agric. Eng."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1007\/s00271-003-0074-6","article-title":"Estimating cotton evapotranspiration crop coefficients with a multispectral vegetation index","volume":"22","author":"Hunsaker","year":"2003","journal-title":"Irrig. Sci."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"73","DOI":"10.1016\/j.agwat.2004.09.023","article-title":"Different irrigation methods and water stress effects on potato yield and yield components","volume":"73","author":"Onder","year":"2005","journal-title":"Agric. Water Manag."},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"148","DOI":"10.1016\/j.agwat.2015.10.027","article-title":"Irrigation and nitrogen effects on tuber yield and water use efficiency of heritage and modern potato cultivars","volume":"170","author":"Fandika","year":"2016","journal-title":"Agric. Water Manag."},{"key":"ref_62","doi-asserted-by":"crossref","unstructured":"Djaman, K., Irmak, S., Koudahe, K., and Allen, S. (2021). Irrigation management in potato (Solanum tuberosum L.) production: A Review. Sustainability, 13.","DOI":"10.3390\/su13031504"}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/15\/18\/4579\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T20:52:36Z","timestamp":1760129556000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/15\/18\/4579"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,9,17]]},"references-count":62,"journal-issue":{"issue":"18","published-online":{"date-parts":[[2023,9]]}},"alternative-id":["rs15184579"],"URL":"https:\/\/doi.org\/10.3390\/rs15184579","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,9,17]]}}}