Identificación molecular de pelotones de hongos micorrízicos de orquídeas tropicales del Sur de Ecuador

Abstract

Abstract: Mycorrhizal fungi are fundamental in the symbiosis with orchids, as they promote seed germination and nutrient supply. Their inoculation is essential for the conservation and production of these plants, ensuring seedling development. However, the lack of information and standardized protocols for isolating truly mycorrhizal fungi limits their cultivation under controlled conditions. The objective of this research was to isolate and molecularly identify platoons of mycorrhizal fungi present in the roots of tropical orchids from southern Ecuador. Forty root samples of Stanhopea tigrina, Epidendrum secundum, and Pleurothallis kashi-menkakarai were collected from a secondary forest in San Pedro de Vilcabamba, Loja province. Of these, 25 showed colonization by platoons after methylene blue staining. The root cuttings were cultured in YPD and PDB liquid media, achieving mycelial growth in 51 cultures. Seven isolates showed microscopic features compatible with Basidiomycota, and five were confirmed by PCR of the ITS and RPB2 regions. This work expands our knowledge of the fungal diversity associated with tropical orchids and proposes a novel protocol for the identification of mycorrhizal fungi.