<?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>S0120-99652018000300248</article-id>
<article-id pub-id-type="doi">10.15446/agron.colomb.v36n3.71268</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Effect of sowing density on yield and profitability of a hybrid corn under tropical conditions]]></article-title>
<article-title xml:lang="es"><![CDATA[Efecto de la densidad de siembra en el rendimiento y rentabilidad de un híbrido de maíz en condiciones tropicales]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Quevedo]]></surname>
<given-names><![CDATA[Yeison Mauricio]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Beltrán]]></surname>
<given-names><![CDATA[José Isidro]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Barragán-Quijano]]></surname>
<given-names><![CDATA[Eduardo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Corporación Colombiana de Investigación Agropecuaria  ]]></institution>
<addr-line><![CDATA[Tolima ]]></addr-line>
<country>Colombia</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2018</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2018</year>
</pub-date>
<volume>36</volume>
<numero>3</numero>
<fpage>248</fpage>
<lpage>256</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S0120-99652018000300248&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S0120-99652018000300248&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S0120-99652018000300248&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[ABSTRACT A high sowing density in maize is a widely used management practice for increasing crop yield; this method increases intraspecific competition for solar radiation, nutrients and water, so yield per plant is reduced, but a greater number of plants is harvested. However, different corn hybrids present a differential behavior because some are tolerant and some are susceptible to this condition, as determined by their plasticity in adjusting their morphology and phenology. The aim of this study was to identify the optimum sowing density, in technical and economic terms, of a new hybrid corn named 30K73 YG RRFlex since no information is available for tropical conditions. This study was carried out in the province of Tolima, municipality of Valle de San Juan, Colombia, using a completely randomized block design in divided plots; five sowing densities determined by six spatial arrangements, two distances between rows (0.7 and 0.8 m) and three numbers of plants per linear meter (7, 8 and 9) were assessed. The treatments did not generate a nitrogen deficiency in the plants, and the evaluated hybrid developed morphological adjustments at the leaf level in order to maintain constant solar radiation interception. For yield, there were no significant variations, so the yield was similar for all of the evaluated treatments. The best treatment was 87,500 plants ha-1, with a yield of 9,916.66 ± 1,078 kg ha-1 and a profitability of 58%.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen El uso de altas densidades poblacionales en cultivos de maíz se considera una práctica de manejo muy usada para incrementar el rendimiento del cultivo; este método de siembra aumenta la competencia intraespecífica por radiación solar, nutrientes y agua, por lo que el rendimiento por planta se ve reducido, pero se compensa por el mayor número de plantas cosechadas. Sin embargo, los diferentes híbridos de maíz tienen un comportamiento diferencial pues algunos son tolerantes o susceptibles a esta condición. Esto es determinado por la plasticidad del material para ajustar su morfología y fenología. El objetivo de este trabajo fue identificar la densidad poblacional óptima en términos técnicos y económicos, para un nuevo hibrido de maíz 30K73 YG RRFlex, del que no se conocía una recomendación a nivel de trópico. Este trabajo fue realizado en el departamento del Tolima, municipio del Valle de San Juan, Colombia, usando un diseño en bloques completos al azar en parcelas divididas; allí se evaluaron cinco densidades poblacionales determinadas por seis arreglos espaciales dados por dos distancias entre surcos (0.7 m y 0.8 m) y tres números de plantas por metro lineal (7, 8 y 9). Allí se encontró que los tratamientos no generaron deficiencia de nitrógeno en las plantas. Además este hibrido desarrolló un ajuste morfológico a nivel foliar para mantener constante la intercepción de radiación solar. En cuanto a rendimiento se encontró que no se presentaron variaciones significativas, por lo que el rendimiento fue similar para los tratamientos evaluados, de tal forma que el mejor tratamiento fue de 87,500 plantas ha-1 con un rendimiento de 9,916.66 ± 1,078 kg ha-1 y una rentabilidad del 58%.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[seeding density]]></kwd>
<kwd lng="en"><![CDATA[nutritional status]]></kwd>
<kwd lng="en"><![CDATA[crop yield]]></kwd>
<kwd lng="en"><![CDATA[growth]]></kwd>
<kwd lng="es"><![CDATA[densidades poblacionales]]></kwd>
<kwd lng="es"><![CDATA[estado nutricional]]></kwd>
<kwd lng="es"><![CDATA[rendimiento de cultivo]]></kwd>
<kwd lng="es"><![CDATA[crecimiento]]></kwd>
</kwd-group>
</article-meta>
</front><back>
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