شیوع بیماری پوسیدگی طوقه و ریشه درختان انجیر(Ficus carica) در شهر کرمان

Crown and root rot is one of the most important diseases of fig (Ficus carica) trees caused by Phytophthora species. Phytophthora species infecting broad range of plants, including forest trees, oil crops, vegetables, fruit, and ornamental plants worldwide. So far, different species of phytophthora including P.cinammomi, P. nicotianae, P. niederhouserii, P.palmivora and P. parasitica have been reported from the world and P.parsiana and P. cryptogea have been reported from Iran as the cause of crown and root rot of fig trees. During a survey in June 2022, following observation of yellowing and wilting of fig leaves in Kerman city, sampling was conducted from trees with crown and root rot symptoms. After washing with sterile distilled water and drying on filter paper, the infected tissue were cultured onto CMA based medium enriched with antibiotics: penicillin, ampicillin, rifampicin plus PCNB. Pure cultures were obtained by transferring hyphal tips to water-agar medium. Moreover, morphological features were investigated and sporangia were persistent, had one or two papillae and the shape of the sporangia were spherical, ovoid or reversed pear-shape. The pathogenicity test was performed on cut fig branches under laboratory conditions using stem under-bark inoculation assay. Two weeks post inoculation, production and extension of lesions was recorded. The results of examining the morphological characteristics of isolates and also sequencing the ITS rDNA region, confirmed that isolates belong to Phytophthora nicotianae.