First report of Melampsora ferrinii (Pucciniales) on Babylon willow (Salix babylonica) in Iran

As an agroforestry resource willow species (Salix spp.) becoming increasingly important in the protection of riverbanks, recovery of floodable lands, soil bioremediation, biomass production, and wicker furniture manufacture, Babylon willow (Salix babylonica) is widely planted all over the world and is found throughout Iran as part of the rural landscape and is mostly planted for ornamental or bioremediation purposes. Rust fungi in the genus Melampsora usually cause disease on Salix species. Identification of Melampsora species is often complicated because there are few differences in spore morphology and little is publicly available in comparative sequence data. Willow trees in Iran have been reported to be infected by 15 Melampsora species; however, most of these records are based on morphological characterization. During surveillance activities carried out in June 2007, a rust species was detected on isolated Babylon willow trees in an area in Northern Iran. Both the rust fungus and the host plant were identified on the basis of morphological features and DNA sequencing. Based on a combination of morphology, large subunit (LSU) rDNA sequencing and phylogenetic analyses, our rust specimen was identified as Melampsora ferrinii, which is newly reported from Iran on Salix babylonica. Melampsora ferrinii was originally described from the Americas and this is the first time that this rust has been observed on its telial host, Babylon willow, in Asia. The documentation of the rust fungus was performed using both scanning electron microscopy (SEM) and light microscopy. Additionally, an identification key for Melampsora species reported on Salix spp. in Iran is included.