<?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>0187-5779</journal-id>
<journal-title><![CDATA[Terra Latinoamericana]]></journal-title>
<abbrev-journal-title><![CDATA[Terra Latinoam]]></abbrev-journal-title>
<issn>0187-5779</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Mexicana de la Ciencia del Suelo A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0187-57792013000300095</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Uso de sensores ópticos para la fertilización de trigo (Triticum aestivum L.)]]></article-title>
<article-title xml:lang="en"><![CDATA[Use of optical sensor technology for the fertilization of wheat (Triticum aestivum L.)]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Santillano-Cázares]]></surname>
<given-names><![CDATA[Jesús]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[López-López]]></surname>
<given-names><![CDATA[Ángel]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ortiz-Monasterio]]></surname>
<given-names><![CDATA[Iván]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Raun]]></surname>
<given-names><![CDATA[W. R.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Autónoma de Baja California Instituto de Ciencias Agrícolas ]]></institution>
<addr-line><![CDATA[Mexicali B. C.]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad Autónoma de Baja California Centro de Capacitación y Seguimiento ]]></institution>
<addr-line><![CDATA[Mexicali B. C.]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,Centro Internacional de Mejoramiento de Maíz y Trigo  ]]></institution>
<addr-line><![CDATA[México D. F.]]></addr-line>
<country>México</country>
</aff>
<aff id="Af4">
<institution><![CDATA[,Oklahoma State University Department of Plant and Soil Sciences ]]></institution>
<addr-line><![CDATA[Stillwater OK]]></addr-line>
<country>USA</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2013</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2013</year>
</pub-date>
<volume>31</volume>
<numero>2</numero>
<fpage>95</fpage>
<lpage>103</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0187-57792013000300095&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0187-57792013000300095&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0187-57792013000300095&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen: A pesar de su importancia económica, la producción de trigo en el valle de Mexicali, B.C., México, atraviesa por dificultades debido a su baja rentabilidad. Una de las causas radica en que los productores podrían estar utilizando más fertilizantes nitrogenados de los necesarios. Además, el nitrógeno (N) que no es recuperado por el cultivo se pierde al ambiente por lixiviación, volatilización, desnitrificación o escurrimiento, acentuando los problemas de contaminación. Una estrategia innovadora, es el uso de sensores ópticos (GreenSeeker®) en combinación con un algoritmo matemático y una franja rica en nitrógeno, lo cual está actualmente demostrando eficacia en el manejo sustentable de los fertilizantes a nivel mundial. Los objetivos de este trabajo fueron: (1) generar una ecuación de predicción confiable de los rendimientos de trigo cultivados localmente y (2) comparar los rendimientos de trigo, dosis de fertilizante y costos de fertilización química, obtenidos mediante la estrategia basada en el uso de sensores, contra la práctica de fertilización convencional de los productores. Se establecieron trabajos de calibración, validación y transferencia de tecnología de 2010 a 2012. Se obtuvo una ecuación de predicción del rendimiento, que demostró ser útil en la recomendación de dosis óptimas de fertilizante nitrogenado. No se detectó reducción en los rendimientos al comparar la práctica convencional de los productores y el uso de sensores (P = 0.2713), la fertilización media aplicada, de acuerdo con la tecnología del uso de sensores, fue inferior en 68 kg de N ha-1 en comparación con la aplicada por los productores acorde a la práctica convencional (P = 0.0015). Estos ahorros representaron $1339 ha-1. Se concluye que en Mexicali, a través del uso de la tecnología de sensores, es posible obtener ahorros sustanciales en los costos de fertilización nitrogenada de trigo, contribuir a incrementar la rentabilidad para los productores y reducir los impactos ambientales al evitar la aplicación de fertilizantes innecesarios.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Summary: Despite its economic importance, wheat production in the valley of Mexicali, B.C., Mexico, is going through difficult times due to its low profitability. One of the causes of the low profitability of wheat production may reside in farmers' using more nitrogen (N) fertilizers than needed. Moreover, the N that is not recovered by the crop is lost to the environment, accentuating pollution issues. One innovative strategy, optical sensor based technology (GreenSeekerTM) along with a mathematical algorithm and a nitrogen rich strip, is showing efficacy for sustainable fertilizer management worldwide. The objectives of this work were two; first, to generate a reliable yield prediction equation for locally grown wheat and second, to compare wheat yields, fertilizer rates and chemical fertilizer costs, using the sensor based technology versus the farmer's conventional fertilization practice. Calibration, validation and technology transfer trials were established from 2010 to 2012. A yield prediction equation was obtained that proved to be useful in recommending optimal fertilizer rates. Without a yield reduction (P = 0.2713), the sensor based technology fertilization mean rate was 68 kg N ha-1 lower than that applied by farmers following their conventional practice (P = 0.0015). These savings (in Mexican currency) accounted for $ 1339 ha-1. It is concluded that in Mexicali, through the use of sensor based technology, it is possible to obtain substantial savings on wheat related fertilizer costs, to contribute to increasing profitability for farmers and to reduce environmental impacts by avoiding unnecessary fertilizer application rates.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[agricultura sustentable]]></kwd>
<kwd lng="es"><![CDATA[GreenSeeker®]]></kwd>
<kwd lng="es"><![CDATA[calibración]]></kwd>
<kwd lng="es"><![CDATA[validación]]></kwd>
<kwd lng="es"><![CDATA[transferencia de tecnología]]></kwd>
<kwd lng="en"><![CDATA[sustainable agriculture]]></kwd>
<kwd lng="en"><![CDATA[GreenSeeker®]]></kwd>
<kwd lng="en"><![CDATA[calibration]]></kwd>
<kwd lng="en"><![CDATA[validation]]></kwd>
<kwd lng="en"><![CDATA[technology transfer]]></kwd>
</kwd-group>
</article-meta>
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