<?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>1405-0471</journal-id>
<journal-title><![CDATA[Madera y bosques]]></journal-title>
<abbrev-journal-title><![CDATA[Madera bosques]]></abbrev-journal-title>
<issn>1405-0471</issn>
<publisher>
<publisher-name><![CDATA[Instituto de Ecología A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1405-04712020000200214</article-id>
<article-id pub-id-type="doi">10.21829/myb.2020.2621716</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Ensayos de tensión y flexión en raíces de dos especies tropicales]]></article-title>
<article-title xml:lang="en"><![CDATA[Tension and bending tests in roots of two tropical species]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Valdés-Rodríguez]]></surname>
<given-names><![CDATA[Ofelia Andrea]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Jiménez Alonso]]></surname>
<given-names><![CDATA[Ángel Eduardo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Servín Martínez]]></surname>
<given-names><![CDATA[Alberto]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Tejero Andrade]]></surname>
<given-names><![CDATA[José]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,El Colegio de Veracruz  ]]></institution>
<addr-line><![CDATA[Xalapa Veracruz]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Tecnológico Nacional de México  ]]></institution>
<addr-line><![CDATA[Veracruz Veracruz]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2020</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2020</year>
</pub-date>
<volume>26</volume>
<numero>2</numero>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S1405-04712020000200214&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S1405-04712020000200214&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S1405-04712020000200214&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen  Las raíces de las plantas permiten evitar la pérdida del suelo al formar mallas que lo retienen, especialmente en suelos arenosos debido a la poca cohesión de estos sustratos; sin embargo, la literatura técnica sobre la ejecución de las pruebas para caracterizar raíces es escasa, por lo que se requiere documentar su caracterización. Los objetivos de este trabajo fueron documentar y caracterizar las propiedades mecánicas de dos raíces de especies tropicales mediante pruebas de tensión y flexión. Para ello se diseñaron dispositivos especiales para sujetar raíces de Jatropha curcas L. y Ricinus communis L. extraídas de suelos arenosos. Las raíces se sometieron a pruebas de tensión y flexión y se estimaron sus módulos de Young en tensión, así como los esfuerzos máximos de flexión. Los módulos de Young en tensión obtenidos variaron en intervalos de 6.27 MPa a 334 MPa para R. comunis y de 4.56 MPa a 271 MPa para J. curcas, con diámetros entre 0.5 mm y 6.8 mm para ambas especies; en las pruebas de flexión las raíces nunca alcanzaron el punto de ruptura, pero los esfuerzos máximos registrados fueron de 21 MPa y 28 MPa, para Ricinus y Jatropha, respectivamente. Se concluye que las raíces de Jatropha y Ricinus poseen módulos de elasticidad muy bajos, similares a otras raíces de especies herbáceas y arbóreas, con una muy alta flexibilidad y comparables con las propiedades del polietileno de baja densidad.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract Plant roots help to avoid soil loss since they form meshes that retain it, especially in sandy soils with low cohesion. However, technical documentation over the execution of tests to characterize roots is scarce; therefore, a detailed approach is required in order to perform reliable studies. The objectives of this work are to document and characterize the mechanical properties of the roots of two tropical species through tension and bending tests. To this end, special devices were designed to hold roots of Jatropha curcas L. and Ricinus communis L. extracted from sandy soils. The roots were subjected to tension and bending tests and their corresponding modulus of Young were estimated, as the maximum bending stresses. The Young tension moduli varied between 6.27 MPa to 334 MPa for Ricinus and 4.56 MPa to 271 MPa for Jatropha , with diameters between 0.5 mm and 6.8 mm for both species; during the bending tests, the roots never reached the breaking point, but they registered maximum stress values of 21 MPa and 28 MPa for Ricinus and Jatropha respectively. It is concluded that roots of Jatropha and Ricinus have low moduli of elasticity values, similar to other herbs and trees roots, with a very high flexibility, comparable to low density polyethylene.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Jatropha curcas]]></kwd>
<kwd lng="es"><![CDATA[módulo de Young]]></kwd>
<kwd lng="es"><![CDATA[Ricinus communis]]></kwd>
<kwd lng="es"><![CDATA[suelos arenosos]]></kwd>
<kwd lng="en"><![CDATA[Jatropha curcas]]></kwd>
<kwd lng="en"><![CDATA[Ricinus communis]]></kwd>
<kwd lng="en"><![CDATA[Young modulus]]></kwd>
<kwd lng="en"><![CDATA[sandy soils]]></kwd>
</kwd-group>
</article-meta>
</front><back>
<ref-list>
<ref id="B1">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Azcón-Bieto]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<name>
<surname><![CDATA[Talón]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<source><![CDATA[Fundamentos de Fisiología vegetal. Universitat de Barcelona]]></source>
<year>2013</year>
<volume>1</volume>
<edition>2a</edition>
<publisher-loc><![CDATA[Barcelona, España ]]></publisher-loc>
<publisher-name><![CDATA[McGraw-Hill-Interamericana de España]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B2">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Bourrier]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
<name>
<surname><![CDATA[Kneib]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
<name>
<surname><![CDATA[Chareyre]]></surname>
<given-names><![CDATA[B.]]></given-names>
</name>
<name>
<surname><![CDATA[Fourcaud]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Discrete modeling of granular soils reinforcement by plant roots]]></article-title>
<source><![CDATA[Ecological Engineering]]></source>
<year>2013</year>
<volume>61</volume>
<numero>1</numero>
<issue>1</issue>
<page-range>646-57</page-range></nlm-citation>
</ref>
<ref id="B3">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Chao-Bo]]></surname>
<given-names><![CDATA[Z.]]></given-names>
</name>
<name>
<surname><![CDATA[Li-Hua]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
<name>
<surname><![CDATA[Jing]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Why fine tree roots are stronger than thicker roots: The role of cellulose and lignin in relation to slope stability]]></article-title>
<source><![CDATA[Geomorphology]]></source>
<year>2014</year>
<volume>206</volume>
<page-range>196-202</page-range></nlm-citation>
</ref>
<ref id="B4">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Cofie]]></surname>
<given-names><![CDATA[P.]]></given-names>
</name>
</person-group>
<source><![CDATA[Mechanical properties of tree roots for soil reinforcement models]]></source>
<year>2001</year>
<publisher-loc><![CDATA[Holand ]]></publisher-loc>
<publisher-name><![CDATA[Wageningen University]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B5">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Cruz Angón]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<name>
<surname><![CDATA[González Díaz]]></surname>
<given-names><![CDATA[M. E.]]></given-names>
</name>
<name>
<surname><![CDATA[Solís Jerónimo]]></surname>
<given-names><![CDATA[S. J.]]></given-names>
</name>
</person-group>
<collab>Comisión Nacional para el Conocimiento y Uso de la Biodiversidad [Conabio]</collab>
<source><![CDATA[Estrategia para la conservación y uso sustentable de la biodiversidad]]></source>
<year>2013</year>
<edition>1a</edition>
<publisher-loc><![CDATA[Xalapa, México ]]></publisher-loc>
<publisher-name><![CDATA[CONABIO]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B6">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Davalos-Sotelo]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Determination of elastic properties of clear wood by the homogenization method in two dimensions]]></article-title>
<source><![CDATA[Wood Science and Technolog]]></source>
<year>2005</year>
<volume>39</volume>
<numero>5</numero>
<issue>5</issue>
<page-range>385-417</page-range></nlm-citation>
</ref>
<ref id="B7">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Dávalos Sotelo]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Comportamiento de la madera como material estructural: estado del conocimiento]]></article-title>
<source><![CDATA[Ciencia]]></source>
<year>1996</year>
<volume>47</volume>
<page-range>76-91</page-range></nlm-citation>
</ref>
<ref id="B8">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Giadrossich]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
<name>
<surname><![CDATA[Schwarz]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Cohen]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
<name>
<surname><![CDATA[Cislaghi]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<name>
<surname><![CDATA[Vergani]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
<name>
<surname><![CDATA[Hubble]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
<name>
<surname><![CDATA[Stokes]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Methods to measure the mechanical behaviour of tree roots: A review]]></article-title>
<source><![CDATA[Ecological Engineering,]]></source>
<year>2017</year>
<page-range>1-16</page-range></nlm-citation>
</ref>
<ref id="B9">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[López-Amo]]></surname>
<given-names><![CDATA[F.]]></given-names>
</name>
<name>
<surname><![CDATA[Pons]]></surname>
<given-names><![CDATA[J. M.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Método de ensayo para la determinación del módulo inicial de elasticidad de las fibras individuales]]></article-title>
<source><![CDATA[Boletín Intexter del Instituto de Investigación Textil y de Cooperación Industrial]]></source>
<year>1981</year>
<volume>80</volume>
<page-range>15-23</page-range></nlm-citation>
</ref>
<ref id="B10">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Mickovski]]></surname>
<given-names><![CDATA[S. B. S. B.]]></given-names>
</name>
<name>
<surname><![CDATA[Stokes]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
<name>
<surname><![CDATA[van Beek]]></surname>
<given-names><![CDATA[R.]]></given-names>
</name>
<name>
<surname><![CDATA[Ghestem]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Fourcaud]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Simulation of direct shear tests on rooted and non-rooted soil using finite element analysis]]></article-title>
<source><![CDATA[Ecological Engineering]]></source>
<year>2011</year>
<volume>37</volume>
<numero>10</numero>
<issue>10</issue>
<page-range>1523-32</page-range></nlm-citation>
</ref>
<ref id="B11">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Niklas]]></surname>
<given-names><![CDATA[K. J.]]></given-names>
</name>
</person-group>
<source><![CDATA[Plant Biomechanics: An engineering approach to plant form and function. Brittonia]]></source>
<year>1992</year>
<volume>46</volume>
<edition>1a</edition>
<publisher-loc><![CDATA[Chicago ]]></publisher-loc>
<publisher-name><![CDATA[The University of Chicago Press]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B12">
<nlm-citation citation-type="">
<source><![CDATA[Polietileno baja densidad]]></source>
<year>2015</year>
</nlm-citation>
</ref>
<ref id="B13">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Saifuddin]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Osman]]></surname>
<given-names><![CDATA[N.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Evaluation of hydro-mechanical properties and root architecture of plants for soil reinforcement]]></article-title>
<source><![CDATA[Current Science]]></source>
<year>2014</year>
<volume>107</volume>
<numero>5</numero>
<issue>5</issue>
<page-range>845-52</page-range></nlm-citation>
</ref>
<ref id="B14">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Sanchez-Castillo]]></surname>
<given-names><![CDATA[L.]]></given-names>
</name>
<name>
<surname><![CDATA[Kubota]]></surname>
<given-names><![CDATA[T.]]></given-names>
</name>
<name>
<surname><![CDATA[Cantu-Silva]]></surname>
<given-names><![CDATA[I.]]></given-names>
</name>
<name>
<surname><![CDATA[Yañez-Diaz]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Hasnawir]]></surname>
</name>
<name>
<surname><![CDATA[Pequeño-Ledezma]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Comparisons of the root mechanical properties of three native Mexican tree species for soil bioengineering practices]]></article-title>
<source><![CDATA[Botanical Sciences]]></source>
<year>2017</year>
<volume>95</volume>
<numero>2</numero>
<issue>2</issue>
<page-range>259-69</page-range></nlm-citation>
</ref>
<ref id="B15">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Sánchez-Echeverri]]></surname>
<given-names><![CDATA[L. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Aita]]></surname>
<given-names><![CDATA[G.]]></given-names>
</name>
<name>
<surname><![CDATA[Robert]]></surname>
<given-names><![CDATA[D.]]></given-names>
</name>
<name>
<surname><![CDATA[Rodriguez Garcia]]></surname>
<given-names><![CDATA[M. E.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Correlation between chemical compounds and mechanical response in culms of two different ages of Guadua angustifolia Kunth]]></article-title>
<source><![CDATA[Madera y Bosques]]></source>
<year>2014</year>
<volume>20</volume>
<numero>2</numero>
<issue>2</issue>
<page-range>87-94</page-range></nlm-citation>
</ref>
<ref id="B16">
<nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Segura]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Introducción al desarrollo. Concepto de hormona vegetal]]></article-title>
<person-group person-group-type="editor">
<name>
<surname><![CDATA[Azcón-Bieto]]></surname>
<given-names><![CDATA[J.]]></given-names>
</name>
<name>
<surname><![CDATA[Talón]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<source><![CDATA[Fundamentos de fisiología vegetal]]></source>
<year>2013</year>
<volume>1</volume>
<edition>2a</edition>
<page-range>357-76</page-range><publisher-loc><![CDATA[Barcelona, España ]]></publisher-loc>
<publisher-name><![CDATA[McGraw-Hill-Interamericana de España]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B17">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Tosi]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Root tensile strength relationships and their slope stability implications of three shrub species in the Northern Apennines (Italy)]]></article-title>
<source><![CDATA[Geomorphology]]></source>
<year>2007</year>
<volume>87</volume>
<numero>4</numero>
<issue>4</issue>
<page-range>268-83</page-range></nlm-citation>
</ref>
<ref id="B18">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Valdés-Rodríguez]]></surname>
<given-names><![CDATA[O. A.]]></given-names>
</name>
<name>
<surname><![CDATA[Pérez-Vázquez]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Seedling characteristics of three oily species before and after root pruning and transplant]]></article-title>
<source><![CDATA[Plants]]></source>
<year>2019</year>
<volume>8</volume>
<numero>8</numero>
<issue>8</issue>
<page-range>258</page-range></nlm-citation>
</ref>
<ref id="B19">
<nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Zhang]]></surname>
<given-names><![CDATA[X.]]></given-names>
</name>
<name>
<surname><![CDATA[Guo]]></surname>
<given-names><![CDATA[Q.]]></given-names>
</name>
<name>
<surname><![CDATA[Xu]]></surname>
<given-names><![CDATA[Y.]]></given-names>
</name>
<name>
<surname><![CDATA[Li]]></surname>
<given-names><![CDATA[P.]]></given-names>
</name>
<name>
<surname><![CDATA[Chen]]></surname>
<given-names><![CDATA[C.]]></given-names>
</name>
<name>
<surname><![CDATA[Wu]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Mechanical testing of tomato plant stem in relation to structural composition]]></article-title>
<source><![CDATA[Agricultural Research]]></source>
<year>2016</year>
<volume>5</volume>
<numero>3</numero>
<issue>3</issue>
<page-range>236-45</page-range></nlm-citation>
</ref>
</ref-list>
</back>
</article>
