Diversidad y composición de la comunidad de Hongos micorrízicos en tres poblaciones de Stelis superbiens, la especie de orquídea epífita más común en un bosque tropical del Sur de Ecuador.

Abstract

Biotic interactions play essential roles in the composition and stability of biotic communities. Specifically, mycorrhizal interactions are important for the diversity and distribution of orchids. However, it is little known about the factors that determine the structure of the mycorrhizal fungi communities. We analyzed the community of mycorrhizal fungi associated with Stelis superbiens in three sites located in two tropical forests in southern Ecuador. For the characterization of these fungal communities, operational taxonomic units (OTUs) were delimited from the ITS2 region of the ADNnr, using the Illumina MiSeq technology. We obtained 171 OTUs from mycorrhizal fungi, corresponding to Serendipitaceae (59 OTUs), Ceratobasidiaceae (56 OTUs), Tulasnellaceae (49 OTUs) and Atractiellales (7 OTUs). The highest number of mycobionts was present in site 2 and significant differences were found among the mycorrhizal fungal communities from the three sites / populations studied. A group of mycobionts (27 OTUs) was shared among all three sites, whitout specific preference in the orchid-fungal interaction. Our results suggest that S. superbiens is a generalist species, whose fungal communities are site dependent.