Colonización y estructura de la comunidad de hongos micorrízicos arbusculares en Alsophila firma (Cyatheaceae) en bosque mesófilo de montaña en Veracruz, México

• DOI: 10.15517/rbt.v62i4.13324
• Publication Date: 2015-02-27T16:20:04Z
• Authors: Luis A. Lara-Pérez; Juan Carlos Noa-C...; Ángel De Jesús La...; Sergio Hernández-...; Iván Oros-Ortega; Antonio Andrade T...
• Keywords: 0106 biological sciences; secundaria y conservada; QH301-705.5; Biología; número de esporas; tree fern; colonización micorrízica; 15. Life on land; number of spores; 01 natural sciences; índice de diversidad; mycorrhizal colonization; vegetación alterada; diversity index; helecho arborescente; secondary and conserved vegetation; disturbed; Biology (General); Helecho arborescente; Glomeromycota

<p><em>Alsophila firma</em> is a tree fern that is distributed mainly in tropical montane cloud forest (TMCF) and is considered as a threatened species. Arbuscular mycorrrhizal fungi (AMF) have been proposed as an alternative in rescue programs of endangered species. However, our knowledge about diversity of AMF and mycorrhizal status of the species of TMCF is limited. In Mexico TMCF shows different degrees of conservation because of fragmentation and land use change. In this study, we evaluated the level of colonization, richness and abundances of spores of AMF in three fragments with different conservation status: conserved (100 years), secondary vegetation (17 years) and disturbed. For this, soil samples and roots were collected from five individuals of <em>A. firma</em> per site, with at least 100m away from each other; a total of 100cm of roots were analysed per site. Root samples showed AMF and occasionally dark septate fungi (DSF) colonizations. For the overall study, 19 species of AMF were recorded: <em>Gigaspora</em> (7), <em>Acaulospora</em> (4), <em>Glomus</em> (4), <em>Funneliformis</em> (2),<em> Sclerocystis</em> (1) and <em>Scutellospora</em> (1). The dominant species in the three sites were<em> Funneliformis geosporum </em>and<em> Acaulospora scrobiculata. </em>The highest diversity (H’) and evenness (J’) (p&lt;0.05) were found in the conserved site (H’=1.7, J’=0.66), when compared to the secondary vegetation (H’=1.5, J’=0.61), and the disturbed site (H’=0.74, J’=0.41). Statistical analysis showed that the AMF degree of colonization was significantly higher (p&lt;0.05) in the conserved site; although, the disturbed site showed low richness and abundances of AMF, the degree of root colonization did not differ statistically (p&lt;0.05) with the secondary vegetation site. Chao2 (Richness estimation model) showed that the number of analysed samples were sufficient to represent the structure of the AMF communities with values &gt;90%. The present study confirmed that <em>A. firma</em> is a mycorrhizal species that exhibits high levels of colonization even in disturbed sites. We suggest that <em>F. geosporum</em> and <em>A. scrobiculata</em> may have the potential to inoculate the gametophyte and young sporophyte of <em>A. firma, </em>to support restoration programs, because of their abundances and high tolerance to disturbed sites.</p>