جداسازی و شناسایی گونه‌های خانواده Bionectriaceae از درختان گز و تاغ در ایران

Bionectriaceae is known as one of the largest families in the order Hypocreales. Species of this family with vastly diverse ecologies can occur in nature either as endophyte, saprophyte or parasite. During four years of field surveys (2019–2022) conducted on fungal trunk diseases of Tamarisk (Tamarix spp.) and saxaul (Haloxylon spp.) trees in Iran, wood samples were collected from branch and trunk of showing disease symptoms in Kerman, Sistan and Baluchistan, Yazd, Semnan and Hormozgan Provinces. Fungal isolations were made from discolored wood tissues onto potato dextrose agar (PDA). Morphological characteristics along with multilocus analyses of the internal transcribed spacer (ITS) region of nrDNA, the translation elongation factor 1-alpha (tef1-α), β-tubulin (tub2), and RNA polymerase II second largest subunit (rpb2) genes, were used for the identification of the fungal isolates. five species of Bionectriaceae including Clonostachys chloroleuca, Clonostachys viticola, Stilbocrea gracilipes, Stilbocrea macrostoma, and Stilbocrea walteri. Of these, S. macrostoma and Clonostachys viticola were recovered from Tamarix spp. and S. gracilipes and C. chloroleuca were isolated from Haloxylon spp. while, S. walteri was obtained from both tree species. The pathogenicity test was carried out on the branches of Tamarix aphylla and Haloxylon ammodendron. The results of the pathogenicity test showed that the identified species were able to infect, colonise and produce lesions statistically different to those caused by the control treatments. Our work is the first comprehensive study on the fungi associated with trunk disease of tamarisk and saxaul trees worldwide. In addition, all the identified species are also reported for the first time occurring on Tamarix and Haloxylon species