Identification of Pathogenic Fusarium Species Isolated from Potato Tubers in Kurdistan Province

Members of Fusarium species are common pathogens of potato¡ causing dry rot in Iran and entire the world. Therefore¡ the objectives in this study were to isolate and identify disease-causing Fusarium spp. from infected potato tubers in Kurdistan province wet markets based on the morphological and molecular characteristics. Fifty-five isolates of Fusarium were obtained from potato tubers collected from the wet market in different cities of Kurdistan province in Iran. All isolates belonged to F. incarnatum¡ F. oxysporum¡ F. acuminatum¡ F. graminearum¡ and F. solani through morphological characters. All of the isolates were evaluated for their pathogenicity on healthy potato tubers in the planthouse. The tubers rot symptoms were observed on the 21th day after inoculation of Fusarium isolates on the tubers tested. In the tubers inoculation tests¡ lesion sizes were quite variable. Based on the sequence data from translation elongation factor (EF-lα) gene analysis¡ 10 pathogenic Fusarium isolates were divided into five major groups. Although the data obtained from morphological and molecular studies sufficiently supported each other¡ the resulting phylogenetic trees based on TEF-1α dataset clearly distinguished closely related species and distinctly separated all morphological taxa. This is the first report on molecular identification of Fusarium spp. strains isolated from potato tubers in Iran and F. incarnatum was reported for the first time in Iran and F. graminearum was isolated for the first time from potato tubers inIran.