Characterization of fungal agents associated with black locust dieback and decline in Ardabil city

 Ornamental trees decline is an important disease that threatens many ornamental and forest trees in the world, including ash, acacia, black locust, maple, elm and ornamental palms. In the present research, in order to characterize the fungal agents associated with black locust decline in Ardabil, samples were collected from black locust trees with typical dieback and canker symptoms from green spaces. 150 fungal isolates were isolated and purified using routine plant pathology methods. Identification of species was carried out using morphological and molecular sequence data of the ITS regions or TEF gene. In this study, 10 fungal species including Fusarium oxysporum, F. solani, Acremonium sp., Cytospora chrysosperma, Camarosporidiella elongata, Nigrospora sp., Alternaria alternata, Epicoccum nigrum, Chaetomium sp. and Sordaria macrospora were identified. It seems that Camarosporidiella elongata, Cytospora chrysosperma, Fusarium oxysporum and F. solani are likelyinvolved in the vascular obstruction, dieback and eventually black locust trees decline in green space of Ardabil. This is the first study on the occurrence of black locust decline in Iran. Among the identified isolates, Ca. elongata is reported for the first time in Iran. Acremonium sp. and S. macrospora are new reports on black locust host worldwide.