Septoria oenotherae . [Descriptions of Fungi and Bacteria

Abstract

Abstract A description is provided for Septoria oenotherae . Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. DISEASE: Leaf spot. In seed stocks, conidiomata are usually encountered on fragments of pods, stems or leaves, and only rarely on the seeds (SIMPSON et al., 1995). Development of S. oenotherae leads to severe blight, with drying of all the leaves starting from the bottom of the plant. This reduces vitality of the plant, and may cause its death. HOSTS: Calylophus sp., Camissonia sp., Gaura sp., Godetia grandiflora, Ludwigia sp., Oenothera biennis (syn. : Onagra biennis ), Oenothera decumbens, O. lamarkiana, O. muricata, O. odorata, O. sinuata (Onagraceae). [Type host - Oenothera biennis .] GEOGRAPHICAL DISTRIBUTION: Asia: Armenia, Azerbaijan, Republic of Georgia, Kazakhstan, Korea, Russia (Far East). Australasia: New Zealand. Europe: Belgium, Czech Republic, Denmark, Estonia, Germany, Italy, Hungary, Latvia, Lithuania, Moldova, Netherlands, Poland, Portugal, Romania, Russia, UK, Ukraine. North America: Canada (Ontario), USA. TRANSMISSION: By air-borne or splash dispersed conidia from infected plant débris and seed stocks. Septoria oenotherae can be transmitted by infected débris in evening primrose seed stock; disease progress may then be influenced by variety, sanitation and chemical fungicides; further, the low rL (apparent infection rate) values can be taken as indicative of a primarily rain-splash spread disease (SIMPSON et al , 1999).