Septoria Leaf Speck, a New Disease of Sunflower, Caused by Septoria helianthina sp. nov.

Abstract Many strains of a pathogenic fungus were isolated from diseased sunflower leaf tissue. According to their characteristics they belonged to the genus Septoria. Leaf speck symptoms, characteristic for spontaneous infection, were also reproduced by artificial inoculation of sunflower plants in the greenhouse. Comparing the morphological, cultural and pathogenic properties of the isolated fungus with other sunflower pathogens, it was indicated that the strains, originating from diseased sunflower leaves represented a new, so far not described species. Therefore, for the causal agent of this disease, the name Septoria helianthina Petrov & Arsenijevic was suggested.