First report of Botrytis cinerea and Alternaria alternata on Pelargonium grandiflorum in Iran

Large flowered pelargonium (Pelargonium grandiflorum) is a perspective flowering crop which is distributed around the world. The area of its application is quite wide: from room floriculture to design the gardens and parks. Observation of leaf spot symptoms on this plant, which was collected from Alborz province (Karaj) motivated us to find the causal agent(s) of the disease. So, the symptomatic parts were cultured on the PDA medium after surface sterilization. Two fungal colonies were appeared on the culture medium. They were identified as Alternaria alternata and Botrytis cinerea according to the morphological characterizations. Molecular study using the gapdh for Alternaria and ITS regions and rpb2 gene for Botrytis confirmed the result of the morphological identification. In the pathogenicity tests, the same spots on inoculated plants with Alternaria and the same spots plus gray mold symptoms and fungal body on leaves, buds and stems of the inoculated plants with Botrytis were another confirmation. Based on our knowledge, this is the first report of these two fungal species on the Pelargonium grandiflorum in Iran.