Biodiversity and paclitaxel synthesis capability of endophytic fungi of hazelnut trees in Fandoghlou forest of Ardabil

Endophytes are a large and various group of microorganisms that live in the plant tissues without any appreant disease symptoms. Endophytes play an important role in protecting the plants against the biotic and abiotic stresses. The objectives of this study were to isolate and identify the endophytic fungi of hazelnut (Corylus avellana) tree and evaluate the possible effects of the hazelnut different tissues on their communities. Healthy samples (fruit including nut, shell and involucre, leaf, stem and root) were collected from hazelnut tree of Fandoghlo forest in Ardabil, Iran. After surface sterilization, the endophytic fungi were isolated using standard culture methods and identified based on morphological characteristics. Representatives of each taxon were identified by sequencing of ITS1-5.8S-ITS2 rDNA region. Tissue colonization frequency, species isolation rate and diversity indices were calculated. In total, 79 endophytic fungal isolates were isolated from fruits (29.9%), leaves (9.1%), stems (54.5%) and roots (9.1%). The isolates belonged to the taxa of Clonostachys sp., Briansuttonomyces sp., Chaetomium sp., Colletotrichum sp., Fusarium sp., Curvularia sp., Epicoccum sp. and Biscogniauxia sp. Accordingly, 15.2% isolates (12 isolates) were not identified due to lack of sporulation. The stem and leaf of the hazelnut tree showed the highest and the lowest colonization frequency, respectively. The indices of diversity of leaf and fruit endophytes were higher than those of roots and stems. The results of thin layer chromatography analysis and polymerase chain reaction (with DBAT gene primer) showed that three isolates are probably able to produce paclitaxel.