<?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>S0187-57792015000300251</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Evaluación técnica y financiera del cultivo de lechuga en invernadero, como alternativa para invierno]]></article-title>
<article-title xml:lang="en"><![CDATA[Technical and financial evaluation of greenhouse lettuce crop as a winter alternative]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Martínez Carrillo]]></surname>
<given-names><![CDATA[Gerardo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Lara Herrera]]></surname>
<given-names><![CDATA[Alfredo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Padilla Bernal]]></surname>
<given-names><![CDATA[Luz Evelia]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Luna Flores]]></surname>
<given-names><![CDATA[Maximino]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Avelar Mejía]]></surname>
<given-names><![CDATA[J. Jesús]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Llamas Llamas]]></surname>
<given-names><![CDATA[J. Jesús]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Autónoma de Zacatecas Unidad Académica de Agronomía ]]></institution>
<addr-line><![CDATA[Zacatecas Zac.]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad Autónoma de Zacatecas Unidad Académica de Contaduría y Administración ]]></institution>
<addr-line><![CDATA[Zacatecas Zac.]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>09</month>
<year>2015</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>09</month>
<year>2015</year>
</pub-date>
<volume>33</volume>
<numero>3</numero>
<fpage>251</fpage>
<lpage>260</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0187-57792015000300251&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0187-57792015000300251&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0187-57792015000300251&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen: Los cultivos que se producen en invernadero sin calefacción en el Altiplano de México y específicamente en Jerez de García Salinas, Zacatecas, no se adaptan en invierno, época en la que no se usan los invernaderos. Con el fin de encontrar una opción de producción que sea económicamente rentable en la época invernal para los productores de esta región, se evaluó la producción de lechuga (Lactuca sativa L.) posterior a un cultivo de tomate. La investigación se realizó en un invernadero tipo multitunel con control pasivo del clima, el cultivo fue establecido en suelo. Se evaluó la combinación de tres variedades (Durango, Orejona PX y EZ-1) y tres densidades de plantación (20, 6.6 y 5 plantas m-2) en la producción y la rentabilidad. El rendimiento con la variedad Durango fue superior en 1.22 y 1.18 veces a EZ-1 y Orejona PX, respectivamente; la densidad de 20 plantas m-2 presentó un rendimiento en kg m-2 de 2.1 y 2.7 veces mayor que con 6.6 y 5 plantas m-2, respectivamente; sin embargo, el peso por planta tuvo comportamiento inverso al peso por metro cuadrado; con cinco plantas m-2 el peso por planta fue mayor en 1.01 y 1.49 veces respecto a 6.6 y 20 plantas m-2, respectivamente. La relación beneficio/costo con el cultivo de tomate fue de 1.28 y con tomate + lechuga fue de 1.37, 1.30 y 1.29 con 20, 6.6 y 5 plantas m-2, respectivamente; por lo cual el cultivo de lechuga, principalmente con la variedad Durango y la densidad de 20 plantas m-2, es una opción recomendable.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract: In Jerez, Zacatecas, the effect of three varieties and three planting densities on yield and economic profitability of a lettuce crop in a medium-technology multitunnel-type greenhouse was evaluated and compared, in the winter period after a tomato crop. The experiment was set up under a factorial arrangement with three treatments (lettuce varieties Durango, Orejona PX and EZ-1) combined with three planting densities (20, 6.6 and 5 plants m-2) in a complete block design with four replications. The variables evaluated were yield, leaf, stem and root fresh weight, and profitability. Durango variety yield was 1.22 and 1.18 times higher than that of EZ-1 and PX Orejona, respectively. Density of 20 plants m-2 yielded (kg m-2) 2.1 and 2.7 times more than the density of 6.6 and 5 plants m-2, respectively. However, weight per plant was contrary to weight per square meter: 5 plants m-2 weighed 1.01 to 1.49 times more than 6.6 and 20 plants m-2, respectively. The benefit/cost relationship of the tomato crop was 1.28, while that of tomato + lettuce was 1.37, 1.29, 1.30 with 20, 6.6 and 5 plants m-2, respectively. Therefore, lettuce, mainly the Durango variety at a density of 20 plants m-2 is a recommended option for winter cropping.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Lactuca sativa L.]]></kwd>
<kwd lng="es"><![CDATA[variedades de lechuga]]></kwd>
<kwd lng="es"><![CDATA[densidad de plantas]]></kwd>
<kwd lng="es"><![CDATA[rentabilidad]]></kwd>
<kwd lng="en"><![CDATA[Lactuca sativa L.]]></kwd>
<kwd lng="en"><![CDATA[varieties of lettuce]]></kwd>
<kwd lng="en"><![CDATA[planting densities]]></kwd>
<kwd lng="en"><![CDATA[profitability]]></kwd>
</kwd-group>
</article-meta>
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