Isolation and Identification of Maple Tar Spot Pathogen in Acer velutinum Trees in Dr. Bahramnia Educational and Research Forest

Maple tap spot is one of the fungal diseases which has been infected maple trees. Early deciduous, the disappearance of leaf, reduction of growth, seed and wood production of maple trees are resulted due to this disease. The objective of this research was isolation and identification of the pathogen on leaves of Acer velutinum in Dr. Bahramnia educational and research forest (Shast-Kalateh of Gorgan). After sampling and culture of explants in PDA medium, growing of fungal pathogen was white delete and fluffy shape. Pathogenic fungi were identified after purification and isolation and characterization of spore, color, shape and disease symptoms. In PDA liquid medium, a scus of fungi was white and a clubbing shape with the fiber shape and linear ascospores was observed inside them. Upon the results, the identified fungal pathogen was Rhytisma acerinum on maple trees in this area.