Notes on powdery mildew of evergreen spindle Euonymus japonicus in Iran

Since the beginning of the 20th</sup> century, several scientific names have been used for the causal agent of powdery mildew on evergreen spindle Euonymus japonicus</em>. The nomenclature of this powdery mildew is reviewed and using Erysiphe euonymicola</em> as current name for the species is suggested. Information on the history of occurrence, natural host range and distribution of E. japonicus</em> powdery mildew in Iran is provided. Morphological differences between E. euonymicola</em> and E. euonymi</em>, a powdery mildew on other species of Euonymus</em> in Europe is discussed.