Fungi diversity in roots of Guarianthe skinneri in urban condition: velamen versus cortex

Abstract

Objective: To Identify the endophytic fungal community of the G. skinneri root in urban populations, showing differences in composition between velamen and cortex to better understand the fungus-root interaction in these orchids.
 Design/Methodology/Approach: We collected tissues from velamen and root from five specimens of G. skinneri growing on urban trees in Tapachuala, Chiapas. We extracted DNA, PCR amplified the ITS marker, sequenced on the Illumina platform followed by diversity analyses and taxonomic assignment.
 Results: We detected 845 OTUs that were assigned to the Fungi kingdom. Velamen and cortex share 403 OTUs, 402 were found exclusively in velamen and 40 in cortex. Besides orchid mycorrhiza forming fungi, we detected other species (e.g Alternaria sp., Beauveria sp., Fusarium sp., Glomus sp. and Tricoderma sp.) that could be involved in root physiology during development and defense against pathogens and predators
 Study Limitations/Implications: Metagenomic studies provide substantial amounts of data that go beyond conventional studies. However, the information generated is still limited regarding the role of each endophyte.
 Findings/Conclusions: Despite these limitations, our work fills a knowledge gap because we detected endophytes that were previously unknown for G. skinneri, leading to new research questions about root-endophyte relationships.