The endophytic fungi isolated from oak trees (Quercus brantii Lindl and Quercus infectoria Oliv.)

Fungal endophytes are a known part of biodiversity associated with plants. They can colonize all parts of the host plant tissues and play an important role in enhancing plant health. Also, they can compete with the pathogens for the same niches and thereby reduce disease severity in plant. In order to identify endophytic fungi of oak trees, healthy plant samples including twigs, stems and leaves were collected from forest regions of Kurdistan province. Samples were cut into 2-cm-long segments. Then, pieces of samples were surface sterilized in 5% sodium hypochlorite and 70% ethanol and rinsed with sterile water three times. Then, samples blotted dry on sterilized filter paper and were cultured on Potato Dextrose Agar (PDA) medium amended with Doxycycline antibiotic 25 oC. A total number of 75 isolates were obtained. Based on morphological characteristics and ITS- rDNA regions sequence data, seven different fungal species including Peyronellaea glomerata, Truncatella angustata, Ulocladium botrytis, Microsphaeropsis olivacea, Chaetomium subaffine, Trichoderma citrinoviride and Trichoderma atroviride were identified as endophytic fungi of oak trees in Kurdistan Province. Chaetomium subaffine and Ulocladium botrytis were among the fungi showing the highest colonization frequency (CF%) in all the tissues analysed. The number of isolated taxa was greater in the stem and trunk of oak trees respectively than those in the other organs analyzed.