Estudio de la diversidad de hongos endófitos asociada a la endósfera foliar de especies forestales nativas y exóticas usando técnicas dependientes de cultivo.

Abstract

The diversity of endophytic fungi associated with the foliar endosphere of two native forest species was studied: Yellow Laurel (Ocotea heterochroma Mez and Sodiro) and Cedar (Cedrela montana Moritz ex Turcz) and two exotics: Eucalyptus (Eucalyptus globulus Labill) and Pine (Pinus radiata D. Don.). This research was conducted in the province of Chimborazo, in the town of Penipe, in El Altar zone. A total of 360 leaflet fragments from 12 individuals were seeded in Potato Dextrose Agar (PDA) culture medium, resulting in 37 morphotypes of endophytes and fungi that were evaluated every 7, 14 and 21 days. After this process, they were individualized for molecular analysis by means of Deoxyribonucleic acid (DNA) of thirty ones that appeared only once were discarded. Sequence assembly was performed, and phylogenetic trees were constructed from nucleotide sequences extracted from the Translation Elongation Factor (TEF) 1-alphagene region. The presence of 9 genera and an order of endophytic fungi was determined, of which the most diverse were Xylaria, Colletotrichum, Pestalotiopsis, Diaporthales with a relative abundance of 72.09%. On the other hand, the remaining 27.91% belonged to the genera Trichoderma, Penicillium, Pyrenochaeta, Coniochaeta and Phaeoacreamonium. The richness index analysis, the Shannon and Simpson Diversity calculation indicated that the diversity of endophytic fungi was found to be present in a higher proportion in native forest species.