Endophytic fungi in roots of native orchids of rupestrian grasslands (campos rupestres) in Serra do Cipó, Brazil

Abstract

Root endophytic fungi are essential to the life cycle of orchids. Many of them act as growth promoters of the host plant and mycorrhizal endophytes are indispensable to seed germination. This study aimed to evaluate the cultivable endophytic fungal richness of five native orchids of rupestrian grasslands (campos rupestres) in Serra do Cipó, Brazil. Healthy roots were sampled and the endophytes isolated, from which total DNA was extracted and the Internal Transcribed Spacer (ITS) region amplified and sequenced. Analysis of 32 fungal sequences permitted the identification of 25 species of the phyla Ascomycota and Basidiomycota. Nine isolates belonged to the Basidiomycota genera Sebacina Tul. & C. Tul. and Tulasnella J. Schröt., which contain important mycorrhizal endophytes of orchids. Same fungal species were obtained from different orchids growing on distinct substrates. Fungal molecular identification indicates high endophyte richness supporting the life cycle of orchids in rupestrian grasslands.