<?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>0864-0394</journal-id>
<journal-title><![CDATA[Pastos y Forrajes]]></journal-title>
<abbrev-journal-title><![CDATA[Pastos y Forrajes]]></abbrev-journal-title>
<issn>0864-0394</issn>
<publisher>
<publisher-name><![CDATA[Estación Experimental de Pastos y Forrajes Indio Hatuey]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0864-03942019000400268</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Actividad de la enzima nitrato reductasa en plántulas de Jatropha curcas L. bajo diferentes porcentajes de sombra]]></article-title>
<article-title xml:lang="en"><![CDATA[Activity of the nitrate reductase enzyme in Jatropha curcas L. seedlings under different shade percentages]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Wencomo-Cárdenas]]></surname>
<given-names><![CDATA[Hilda Beatriz]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Ministerio de Educación Superior Universidad de Matanzas Estación Experimental de Pastos y Forrajes Indio Hatuey]]></institution>
<addr-line><![CDATA[Matanzas ]]></addr-line>
<country>Cuba</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2019</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2019</year>
</pub-date>
<volume>42</volume>
<numero>4</numero>
<fpage>268</fpage>
<lpage>276</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_arttext&amp;pid=S0864-03942019000400268&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_abstract&amp;pid=S0864-03942019000400268&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.sld.cu/scielo.php?script=sci_pdf&amp;pid=S0864-03942019000400268&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen  Objetivo Determinar la influencia de diferentes porcentajes de sombra sobre la actividad de la enzima nitrato reductasa en las hojas y raíces de plántulas de Jatropha curcas L.  Materiales y Métodos Para ello, se probaron tres porcentajes de sombra (30, 50 y 70 %) y un tratamiento a pleno sol en tejidos foliares y radicales; y se determinó el contenido de proteína total soluble y la actividad de la enzima nitrato reductasa. Los datos se procesaron mediante un análisis de varianza simple y de regresión. Todo ello, con el empleo del programa estadístico SPSS® versión 22.0 para Microsoft Windows®.  Resultados  Los valores de la actividad nitrato reductasa fueron más altos en las hojas que en las raíces. Se observaron diferencias en la actividad de la enzima en las hojas, en relación con los porcentajes de sombra evaluados. A los 30 y 60 días de evaluación se halló una relación lineal, con R2 = 0,984 y R2 = 0,945, respectivamente, en la que se observó un decrecimiento de la actividad enzimática a medida que aumentó el porcentaje de sombra.  Conclusiones La actividad de la enzima nitrato reductasa y la proteína soluble disminuyeron de forma lineal con el aumento de los porcentajes de sombra, lo cual indica la importancia de los altos índices de radiación luminosa para el buen funcionamiento del metabolismo del nitrógeno en J. curcas.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract  Objective To determine the influence of three shade percentages on the activity of the nitrate reductase enzyme, in Jatropha curcas L. seedlings.  Materials and Methods  For such purpose, three shade levels (30, 50 and 70 %) and a treatment under full sunlight on leaf and root tissues were tested; and the total soluble protein content and activity of the nitrate reductase enzyme were determined. The data were processed through a simple variance and regression analysis. All this was done using the statistical program SPSS® version 22 for Microsoft Windows®.  Results The values of the nitrate reductase activity were higher in the leaves than in the roots. Differences were observed in the enzyme activity in the leaves, with regards to the evaluated shade percentages. At 30 and 90 days of evaluation a linear relation was found, with R2 = 0,984 and R2 = 0,945, respectively, in which a decrease was observed of the enzymatic activity as the shade percentage increased.  Conclusions The activity of the nitrate reductase enzyme and the soluble protein decreased linearly with the increase of the shade percentages, which indicates the importance of the high indexes of luminous radiation for the good functioning of nitrogen metabolism in J. curcas.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[metabolismo del nitrógeno]]></kwd>
<kwd lng="es"><![CDATA[radiaciones]]></kwd>
<kwd lng="es"><![CDATA[tejidos vegetales]]></kwd>
<kwd lng="en"><![CDATA[nitrogen metabolism]]></kwd>
<kwd lng="en"><![CDATA[radiations]]></kwd>
<kwd lng="en"><![CDATA[plant tissues]]></kwd>
</kwd-group>
</article-meta>
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</person-group>
<source><![CDATA[Guía técnica para el establecimiento y producción del cultivo de Jatropha curcas (tempate) en Costa Rica]]></source>
<year>2012</year>
<publisher-loc><![CDATA[Cartago, Costa Rica ]]></publisher-loc>
<publisher-name><![CDATA[Editorial Tecnológica de Costa Rica]]></publisher-name>
</nlm-citation>
</ref>
</ref-list>
</back>
</article>
