<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0120-9965</journal-id>
<journal-title><![CDATA[Agronomía Colombiana]]></journal-title>
<abbrev-journal-title><![CDATA[Agron. colomb.]]></abbrev-journal-title>
<issn>0120-9965</issn>
<publisher>
<publisher-name><![CDATA[Universidad Nacional de Colombia, Facultad de Agronomía]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0120-99652017000200205</article-id>
<article-id pub-id-type="doi">10.15446/agron.colomb.v35n2.62875</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Relationship between crop nutritional status, spectral measurements and Sentinel 2 images]]></article-title>
<article-title xml:lang="es"><![CDATA[Relación entre el estado nutricional de los cultivos, las mediciones espectrales y las imágenes Sentinel 2]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Martínez M]]></surname>
<given-names><![CDATA[Luis Joel]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Nacional de Colombia Faculty of Agricultura Sciences ]]></institution>
<addr-line><![CDATA[Bogotá ]]></addr-line>
<country>Colombia</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>08</month>
<year>2017</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>08</month>
<year>2017</year>
</pub-date>
<volume>35</volume>
<numero>2</numero>
<fpage>205</fpage>
<lpage>215</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S0120-99652017000200205&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S0120-99652017000200205&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S0120-99652017000200205&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT In order to monitor the nutritional status of some crops based on plant spectroscopy and Sentinel 2 satellite images in Colombia, spectral reflectance data were taken between 350 and 2,500 nm with a FieldSpec 4 spectrometer in rubber, rice, sugar cane, maize, soybean, cashew, oil palm crops, pastures and natural savanna. Furthermore contents of mineral nutrients in leaves were determined. Several vegetation indexes and red edge positions were calculated using various methods from spectral data and Sentinel 2 satellite images and were correlated with leaf nutrient content. The results showed correlations between spectral indices, mainly those involving a spectral response in the red-edge range with the N, P, K and Cu although the best correlation coefficients were for N. First reflectance derivatives, transformations by the State Normal Variate and second reflectance derivatives showed great potential to monitor N content in crops. The green model index and the red-edge model computed from Sentinel 2 images had the best performance to monitor N content, although in the study area, presence of clouds affected the use of these images. The Sentinel 2 images allowed calculating some vegetation indexes obtained with other images, such as Landsat or SPOT, but additionally other indexes and calculations based on the bands of the red-edge, which is a great contribution to obtain more information of crops on their spatial and temporal variability]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[RESUMEN Con el fin de monitorear el estado nutricional de algunos cultivos con base en espectroscopía de plantas e imágenes satelitales 2 en Colombia, se tomaron datos de reflectancia entre 350 y 2.500 nm con un espectrómetro FieldSpec 4 en cultivos de caucho, arroz, caña de azúcar, maíz, soya, marañón y palma de aceite, en pasturas y sabanas naturales y se determinó el contenido de nutrientes minerales en hojas. Se calcularon varios índices de vegetación y posiciones de borde rojo usando varios métodos, a partir de datos espectrales e imágenes de satélite Sentinel 2 y se correlacionaron con el contenido de nutrientes en las hojas. Los resultados mostraron correlaciones entre índices espectrales, principalmente aquellos que involucraron la respuesta espectral en el rango de borde rojo, con N, P, K y Cu aunque los mejores coeficientes de correlación fueron para N. La primera derivada de la reflectancia, su transformación por la state normal variate y la segundas derivadas mostraron un gran potencial para monitorear el contenido de N en los cultivos. El índice del modelo verde y el modelo de borde rojo calculados a partir de imágenes Sentinel 2 tuvieron el mejor desempeño para monitorear el contenido de N, aunque en las condiciones del área de estudio la presencia de nubes afectó el uso de estas imágenes. Las imágenes Sentinel 2 permitieron calcular algunos índices de vegetación que se obtienen con otras imágenes, como Landsat o SPOT, pero adicionalmente otros índices y cálculos basados en las bandas del borde rojo, lo cual es una gran contribución para obtener más información de los cultivos su variabilidad espacial y temporal.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[spectral reflectance]]></kwd>
<kwd lng="en"><![CDATA[spectroradiometry]]></kwd>
<kwd lng="en"><![CDATA[crop nutrition]]></kwd>
<kwd lng="es"><![CDATA[reflectancia espectral]]></kwd>
<kwd lng="es"><![CDATA[espectroradiometría]]></kwd>
<kwd lng="es"><![CDATA[nutrición de cultivos]]></kwd>
</kwd-group>
</article-meta>
</front><back>
<ref-list>
<ref id="B1">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Barnes]]></surname>
<given-names><![CDATA[R]]></given-names>
</name>
<name>
<surname><![CDATA[Dhanoa]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Lister]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Letter: Correction to the description of Standard Normal Variate (SNV) and De-Trend (DT) Transformations in practical spectroscopy with applications in food and beverage analysis]]></article-title>
<source><![CDATA[J. Near Infrar. Spectros]]></source>
<year>1993</year>
<volume>1</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>185</page-range></nlm-citation>
</ref>
<ref id="B2">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Cao]]></surname>
<given-names><![CDATA[Q]]></given-names>
</name>
<name>
<surname><![CDATA[Miao]]></surname>
<given-names><![CDATA[Y]]></given-names>
</name>
<name>
<surname><![CDATA[Feng]]></surname>
<given-names><![CDATA[G]]></given-names>
</name>
<name>
<surname><![CDATA[Gao]]></surname>
<given-names><![CDATA[X]]></given-names>
</name>
<name>
<surname><![CDATA[Li]]></surname>
<given-names><![CDATA[F]]></given-names>
</name>
<name>
<surname><![CDATA[Liu]]></surname>
<given-names><![CDATA[B]]></given-names>
</name>
<name>
<surname><![CDATA[Yue]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
<name>
<surname><![CDATA[Cheng]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
<name>
<surname><![CDATA[Lu]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
<name>
<surname><![CDATA[Khosla]]></surname>
<given-names><![CDATA[R]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Active canopy sensing ofwinter wheat nitrogen status: An evaluation of two sensor systems]]></article-title>
<source><![CDATA[Comput. Electron Agric]]></source>
<year>2015</year>
<volume>112</volume>
<page-range>54-67</page-range></nlm-citation>
</ref>
<ref id="B3">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Chen]]></surname>
<given-names><![CDATA[P]]></given-names>
</name>
<name>
<surname><![CDATA[Haboudane]]></surname>
<given-names><![CDATA[D]]></given-names>
</name>
<name>
<surname><![CDATA[Tremblay]]></surname>
<given-names><![CDATA[N]]></given-names>
</name>
<name>
<surname><![CDATA[Wang]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Vigneault]]></surname>
<given-names><![CDATA[P]]></given-names>
</name>
<name>
<surname><![CDATA[Li]]></surname>
<given-names><![CDATA[B]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[New spectral indicator assessing the efficiency of crop nitrogen treatment in corn and wheat]]></article-title>
<source><![CDATA[Remote Sens. Environ]]></source>
<year>2010</year>
<volume>114</volume>
<numero>9</numero>
<issue>9</issue>
<page-range>1987-97</page-range></nlm-citation>
</ref>
<ref id="B4">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Cho]]></surname>
<given-names><![CDATA[M.A]]></given-names>
</name>
<name>
<surname><![CDATA[Skidmore]]></surname>
<given-names><![CDATA[A.K]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[A new technique for extracting the red edge position from hyperspectral data: The linear extrapolation method]]></article-title>
<source><![CDATA[Remote Sens. Environ]]></source>
<year>2006</year>
<volume>101</volume>
<numero>2</numero>
<issue>2</issue>
<page-range>181-93</page-range></nlm-citation>
</ref>
<ref id="B5">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Cho]]></surname>
<given-names><![CDATA[M.A]]></given-names>
</name>
</person-group>
<source><![CDATA[Hyperspectral remote sensing of biochemical and biophysical parameters: The derivative red-edge "double-peak feature", a nuisance or an opportunity?]]></source>
<year>2007</year>
<publisher-loc><![CDATA[Enschede ]]></publisher-loc>
<publisher-name><![CDATA[Twente University, The Netherlands]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B6">
<nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Congedo]]></surname>
<given-names><![CDATA[L]]></given-names>
</name>
</person-group>
<source><![CDATA[Semi-automatic classification plugin documentation]]></source>
<year>2016</year>
</nlm-citation>
</ref>
<ref id="B7">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Curran]]></surname>
<given-names><![CDATA[P.J]]></given-names>
</name>
<name>
<surname><![CDATA[Dungan]]></surname>
<given-names><![CDATA[J. L]]></given-names>
</name>
<name>
<surname><![CDATA[Macler]]></surname>
<given-names><![CDATA[B. A]]></given-names>
</name>
<name>
<surname><![CDATA[Plumer]]></surname>
<given-names><![CDATA[S. E]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The effect of a red leaf pigment on the relationship between red edge and chlorophyll concentration]]></article-title>
<source><![CDATA[Remote Sens. Environ]]></source>
<year>1991</year>
<volume>35</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>69-76</page-range></nlm-citation>
</ref>
<ref id="B8">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Datt]]></surname>
<given-names><![CDATA[B]]></given-names>
</name>
<name>
<surname><![CDATA[Paterson]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
</person-group>
<source><![CDATA[Vegetation-soil spectral mixture analysis. IGARSS 2000. IEEE 2000 International Geoscience and Remote Sensing Symposium. Taking the Pulse of the Planet: The Role of Remote Sensing in Managing the Environment]]></source>
<year>2000</year>
<volume>5</volume>
<conf-name><![CDATA[ Proceedings (Cat. No. 00CH37120)]]></conf-name>
<conf-loc> </conf-loc>
<page-range>1936-8</page-range></nlm-citation>
</ref>
<ref id="B9">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Delegido]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Verrelst]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Alonso]]></surname>
<given-names><![CDATA[L]]></given-names>
</name>
<name>
<surname><![CDATA[Moreno]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Evaluation of sentinel-2 red-edge bands for empirical estimation of green LAI and chlorophyll content]]></article-title>
<source><![CDATA[Sensors]]></source>
<year>2011</year>
<volume>11</volume>
<numero>7</numero>
<issue>7</issue>
<page-range>7063-81</page-range></nlm-citation>
</ref>
<ref id="B10">
<nlm-citation citation-type="book">
<collab>European Space Agency (ESA)</collab>
<source><![CDATA[SENTINEL-2 User Guide]]></source>
<year>2016</year>
<publisher-name><![CDATA[ESA]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B11">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Filella]]></surname>
<given-names><![CDATA[I]]></given-names>
</name>
<name>
<surname><![CDATA[Peñuelas]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The red edge position and shape as indicator of plant chlorophyll content, biomass and hydric status]]></article-title>
<source><![CDATA[Int. J. Remote Sens]]></source>
<year>1994</year>
<volume>15</volume>
<numero>7</numero>
<issue>7</issue>
<page-range>1459-70</page-range></nlm-citation>
</ref>
<ref id="B12">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Frampton]]></surname>
<given-names><![CDATA[W.J]]></given-names>
</name>
<name>
<surname><![CDATA[Dash]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Watmough]]></surname>
<given-names><![CDATA[G]]></given-names>
</name>
<name>
<surname><![CDATA[Milton]]></surname>
<given-names><![CDATA[E. J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Evaluating the capabilities of Sentinel-2 for quantitative estimation of biophysical variables in vegetation]]></article-title>
<source><![CDATA[ISPRS]]></source>
<year>2013</year>
<volume>82</volume>
<page-range>83-92</page-range></nlm-citation>
</ref>
<ref id="B13">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Gitelson]]></surname>
<given-names><![CDATA[A.A]]></given-names>
</name>
<name>
<surname><![CDATA[Kaufman]]></surname>
<given-names><![CDATA[Y.J]]></given-names>
</name>
<name>
<surname><![CDATA[Merzlyak]]></surname>
<given-names><![CDATA[M.N]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Use of a green channel in remote sensing of global vegetation from EOS-MODIS]]></article-title>
<source><![CDATA[Remote Sens. Environ]]></source>
<year>1996</year>
<volume>58</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>289-98</page-range></nlm-citation>
</ref>
<ref id="B14">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Gitelson]]></surname>
<given-names><![CDATA[A.A]]></given-names>
</name>
<name>
<surname><![CDATA[Merzlyak]]></surname>
<given-names><![CDATA[M.N]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Signature analysis of leaf reflectance spectra: Algorithm development for remote sensing of chlorophyll]]></article-title>
<source><![CDATA[J. Plant Physiol]]></source>
<year>1996</year>
<volume>148</volume>
<numero>3-4</numero>
<issue>3-4</issue>
<page-range>494-500</page-range></nlm-citation>
</ref>
<ref id="B15">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Gitelson]]></surname>
<given-names><![CDATA[A.A]]></given-names>
</name>
<name>
<surname><![CDATA[Merzlyak]]></surname>
<given-names><![CDATA[M.N]]></given-names>
</name>
<name>
<surname><![CDATA[Lichtenthaler]]></surname>
<given-names><![CDATA[H.K]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Detection of red edge position and chlorophyll content by reflectance measurements near 700 nm]]></article-title>
<source><![CDATA[J. Plant Physiol]]></source>
<year>1996</year>
<volume>148</volume>
<numero>3-4</numero>
<issue>3-4</issue>
<page-range>501-8</page-range></nlm-citation>
</ref>
<ref id="B16">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Gitelson]]></surname>
<given-names><![CDATA[A.A]]></given-names>
</name>
<name>
<surname><![CDATA[Viña]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
<name>
<surname><![CDATA[Ciganda]]></surname>
<given-names><![CDATA[V]]></given-names>
</name>
<name>
<surname><![CDATA[Rundquist]]></surname>
<given-names><![CDATA[D. C]]></given-names>
</name>
<name>
<surname><![CDATA[Arkebauer]]></surname>
<given-names><![CDATA[T. J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Remote estimation of canopy chlorophyll content in crops]]></article-title>
<source><![CDATA[Geophys. Res. Lett]]></source>
<year>2005</year>
<volume>32</volume>
<numero>8</numero>
<issue>8</issue>
<page-range>1-4</page-range></nlm-citation>
</ref>
<ref id="B17">
<nlm-citation citation-type="confpro">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Guyot]]></surname>
<given-names><![CDATA[G]]></given-names>
</name>
<name>
<surname><![CDATA[Baret]]></surname>
<given-names><![CDATA[F]]></given-names>
</name>
</person-group>
<source><![CDATA[Utilisation de la haute résolution spectrale pour suivre l'état des couverts végétaux]]></source>
<year>1988</year>
<conf-name><![CDATA[ Proc. 4th International Colloquium on Spectral Signatures of Objects in Remote Sensing]]></conf-name>
<conf-loc>Aussois, France </conf-loc>
<page-range>279-86</page-range></nlm-citation>
</ref>
<ref id="B18">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Immitzer]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Vuolo]]></surname>
<given-names><![CDATA[F]]></given-names>
</name>
<name>
<surname><![CDATA[Atzberger]]></surname>
<given-names><![CDATA[C]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[First experience with Sentinel-2 data for crop and tree species classifications in central Europe]]></article-title>
<source><![CDATA[Remote Sens]]></source>
<year>2016</year>
<volume>8</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>2-27</page-range></nlm-citation>
</ref>
<ref id="B19">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Jordan]]></surname>
<given-names><![CDATA[C.F]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Derivation of leaf-area index from quality of light on the forest]]></article-title>
<source><![CDATA[Ecol]]></source>
<year>1969</year>
<volume>50</volume>
<numero>4</numero>
<issue>4</issue>
<page-range>663-6</page-range></nlm-citation>
</ref>
<ref id="B20">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Kochubey]]></surname>
<given-names><![CDATA[S.M]]></given-names>
</name>
<name>
<surname><![CDATA[Kazantsev]]></surname>
<given-names><![CDATA[T.A]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Changes in the first derivatives of leaf reflectance spectra of various plants induced by variations of chlorophyll content]]></article-title>
<source><![CDATA[J. Plant Physiol]]></source>
<year>2007</year>
<volume>164</volume>
<numero>12</numero>
<issue>12</issue>
<page-range>1648-55</page-range></nlm-citation>
</ref>
<ref id="B21">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Liang]]></surname>
<given-names><![CDATA[S]]></given-names>
</name>
</person-group>
<source><![CDATA[Quantitative remote sensing of land surfaces]]></source>
<year>2004</year>
<publisher-loc><![CDATA[Hoboken, NY, USA ]]></publisher-loc>
<publisher-name><![CDATA[Wiley and Sons]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B22">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Malthus]]></surname>
<given-names><![CDATA[T.J]]></given-names>
</name>
<name>
<surname><![CDATA[Dekker]]></surname>
<given-names><![CDATA[G]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[First derivative indices for the remote-sensing of inland water-quality using high-spectral-resolution reflectance]]></article-title>
<source><![CDATA[Environ. Int]]></source>
<year>1995</year>
<volume>21</volume>
<numero>2</numero>
<issue>2</issue>
<page-range>221-32</page-range></nlm-citation>
</ref>
<ref id="B23">
<nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Martinez]]></surname>
<given-names><![CDATA[L.J]]></given-names>
</name>
<name>
<surname><![CDATA[Ramos]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
</person-group>
<source><![CDATA[Estimation of chlorophyll concentration in maize using spectral reflectance. ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences]]></source>
<year>2015</year>
<page-range>65-71</page-range></nlm-citation>
</ref>
<ref id="B24">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Mulla]]></surname>
<given-names><![CDATA[D.J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Twenty five years of remote sensing in precision agriculture: Key advances and remaining knowledge gaps]]></article-title>
<source><![CDATA[Biosyst. Eng]]></source>
<year>2013</year>
</nlm-citation>
</ref>
<ref id="B25">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Peñuelas]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Garbulsky]]></surname>
<given-names><![CDATA[M.F]]></given-names>
</name>
<name>
<surname><![CDATA[Filella]]></surname>
<given-names><![CDATA[I]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Photochemical reflectance index (PRI) and remote sensing of plant CO2 uptake]]></article-title>
<source><![CDATA[New Phytol]]></source>
<year>2011</year>
<volume>191</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>596-9</page-range></nlm-citation>
</ref>
<ref id="B26">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Qi]]></surname>
<given-names><![CDATA[J]]></given-names>
</name>
<name>
<surname><![CDATA[Inoue]]></surname>
<given-names><![CDATA[Y]]></given-names>
</name>
<name>
<surname><![CDATA[Wiangwang]]></surname>
<given-names><![CDATA[N]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Hyperspectral remote sensing in global change studies]]></article-title>
<source><![CDATA[Hyperspectral remote sensing of vegetation]]></source>
<year>2011</year>
<page-range>69-90</page-range><publisher-name><![CDATA[CRC Press]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B27">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Rouse Jr]]></surname>
<given-names><![CDATA[J.W.,]]></given-names>
</name>
<name>
<surname><![CDATA[Haas]]></surname>
<given-names><![CDATA[R.H]]></given-names>
</name>
<name>
<surname><![CDATA[Schell]]></surname>
<given-names><![CDATA[J.A]]></given-names>
</name>
<name>
<surname><![CDATA[Deering]]></surname>
<given-names><![CDATA[D.W]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Monitoring vegetation systems in the Great Plains with ERTS]]></article-title>
<person-group person-group-type="editor">
<name>
<surname><![CDATA[Freden]]></surname>
<given-names><![CDATA[S.C]]></given-names>
</name>
<name>
<surname><![CDATA[Mercanti]]></surname>
<given-names><![CDATA[E.P]]></given-names>
</name>
<name>
<surname><![CDATA[Becker]]></surname>
<given-names><![CDATA[M.A]]></given-names>
</name>
</person-group>
<source><![CDATA[Third Earth Resources Technology Satellite-1 Symposium- Vol. I: Technical Presentations. NASA SP-351]]></source>
<year>1974</year>
<page-range>309</page-range><publisher-loc><![CDATA[Washington, D.C ]]></publisher-loc>
<publisher-name><![CDATA[NASA]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B28">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Ruiz]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Chen]]></surname>
<given-names><![CDATA[P]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Use of the first derivative of spectral reflectance to detect mold on tomatoes]]></article-title>
<source><![CDATA[Trans. ASAE]]></source>
<year>1982</year>
<volume>25</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>759-62</page-range></nlm-citation>
</ref>
<ref id="B29">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Savitzky]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
<name>
<surname><![CDATA[Golay]]></surname>
<given-names><![CDATA[M.J]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Smoothing and differentiation of data by simplified least squares procedures]]></article-title>
<source><![CDATA[Analyt. Chem]]></source>
<year>1964</year>
<volume>36</volume>
<numero>8</numero>
<issue>8</issue>
<page-range>1627-39</page-range></nlm-citation>
</ref>
<ref id="B30">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Schlemmer]]></surname>
<given-names><![CDATA[M.R]]></given-names>
</name>
<name>
<surname><![CDATA[Francis]]></surname>
<given-names><![CDATA[D.D]]></given-names>
</name>
<name>
<surname><![CDATA[Shanahan]]></surname>
<given-names><![CDATA[J.F]]></given-names>
</name>
<name>
<surname><![CDATA[Schepers]]></surname>
<given-names><![CDATA[J.S]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Remotely measuring chlorophyll content in corn leaves with differing nitrogen levels and relative water content]]></article-title>
<source><![CDATA[Agron. J]]></source>
<year>2005</year>
<volume>97</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>106-12</page-range></nlm-citation>
</ref>
<ref id="B31">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Thorp]]></surname>
<given-names><![CDATA[K.R]]></given-names>
</name>
<name>
<surname><![CDATA[Tian]]></surname>
<given-names><![CDATA[L]]></given-names>
</name>
<name>
<surname><![CDATA[Yao]]></surname>
<given-names><![CDATA[H]]></given-names>
</name>
<name>
<surname><![CDATA[Tang]]></surname>
<given-names><![CDATA[L]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Narrow-band and derivative-based vegetation indices for hyperspectral data]]></article-title>
<source><![CDATA[Trans. ASAE]]></source>
<year>2004</year>
<volume>47</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>291-9</page-range></nlm-citation>
</ref>
<ref id="B32">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Tsai]]></surname>
<given-names><![CDATA[F]]></given-names>
</name>
<name>
<surname><![CDATA[Philpot]]></surname>
<given-names><![CDATA[W]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Derivative analysis of hyperspectral data]]></article-title>
<source><![CDATA[Remote Sens. Environ]]></source>
<year>1998</year>
<volume>66</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>41-51</page-range></nlm-citation>
</ref>
<ref id="B33">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Usha]]></surname>
<given-names><![CDATA[K]]></given-names>
</name>
<name>
<surname><![CDATA[Singh]]></surname>
<given-names><![CDATA[B]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Potential applications of remote sensing in horticulture - A review]]></article-title>
<source><![CDATA[Sci. Hortic]]></source>
<year>2013</year>
<volume>153</volume>
<page-range>71-83</page-range></nlm-citation>
</ref>
<ref id="B34">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Yao]]></surname>
<given-names><![CDATA[H]]></given-names>
</name>
<name>
<surname><![CDATA[Huang]]></surname>
<given-names><![CDATA[Y]]></given-names>
</name>
<name>
<surname><![CDATA[Hruska]]></surname>
<given-names><![CDATA[Z]]></given-names>
</name>
<name>
<surname><![CDATA[Thomson]]></surname>
<given-names><![CDATA[S.J]]></given-names>
</name>
<name>
<surname><![CDATA[Reddy]]></surname>
<given-names><![CDATA[K.N]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Using vegetation index and modified derivative for early detection of soybean plant injury from glyphosate]]></article-title>
<source><![CDATA[Comput. Electron. Agric]]></source>
<year>2012</year>
<volume>89</volume>
<page-range>145-57</page-range></nlm-citation>
</ref>
<ref id="B35">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Yu]]></surname>
<given-names><![CDATA[K]]></given-names>
</name>
<name>
<surname><![CDATA[Wiedemann]]></surname>
<given-names><![CDATA[V. L]]></given-names>
</name>
<name>
<surname><![CDATA[Chen]]></surname>
<given-names><![CDATA[X]]></given-names>
</name>
<name>
<surname><![CDATA[Bareth]]></surname>
<given-names><![CDATA[G]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Estimating leaf chlorophyll of barley at different growth stages using spectral indices to reduce soil background and canopy structure effects]]></article-title>
<source><![CDATA[ISPRS J. Photogrammetry Remote Sens]]></source>
<year>2014</year>
<volume>97</volume>
<page-range>58-77</page-range></nlm-citation>
</ref>
<ref id="B36">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Zhang]]></surname>
<given-names><![CDATA[C]]></given-names>
</name>
<name>
<surname><![CDATA[Kovacs]]></surname>
<given-names><![CDATA[J.M]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[The application of small unmanned aerial systems for precision agriculture: A review]]></article-title>
<source><![CDATA[Precision Agric]]></source>
<year>2012</year>
<volume>13</volume>
<numero>6</numero>
<issue>6</issue>
<page-range>693-712</page-range></nlm-citation>
</ref>
</ref-list>
</back>
</article>
