شناسايي گونه‌هاي فوزاريوم بيماري‌زا جدا شده از غده‌هاي سيب‌زميني در استان كردستان

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

گونه‌هاي فوزاريوم ازجمله قارچهاي بيماريزا در دنيا و ايران هستند كه بر روي سيب­ زميني ايجاد پوسيدگي خشك ميكنند. بنابراين هدف از انجام اين تحقيق شناسايي گونههاي بيماري­ زاي فوزاريوم بر روي سيب­زميني در سطح مغازههاي تره­ بار فروشي موجود در شهرهاي مختلف استان كردستان بود. در اين تحقيق 55 جدايه قارچ فوزاريوم جدا شده از غدههاي آلوده سيبزميني مورد بررسي قرار گرفت كه براساس بررسيهاي ريخت شناسي متعلق به گونههاي Fusarium incarnatum، F. oxysporum،F. acuminatum ،F. graminearum و F. solani بودند. آزمون بيماري­ زايي همه جدايه‌ها بر روي غدههاي سيب­ زميني سالم (رقم مارفونا) ارزيابي شد. از ميان جدايههايي كه بيماري­ زا بودند، ده جدايه براي مطالعات مولكولي انتخاب شدند. بررسي­ هاي مولكولي براساس مقايسه توالي ژن TEF-1α انجام گرديد. بر اين اساس همه ده جدايه در پنج گروه فيلوژنيتيكي قرار گرفتند. در اين تحقيق گونه F. incarnatum براي اولين بار از ايران گزارش و بيماري­ زايي گونه F. graminearum بر روي سيب ­زميني براي اولين بار از ايران گزارش ميشود.

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.