First report of white mold caused by Sclerotinia sclerotiorum on Echium (Echium vulgare).

Echium, also known as common viper's bugloss, is a member of the botanical family Boraginaceae. Echium is being evaluated for its potential use as an oilseed crop in North Dakota. In 2003, 40% of echium plants in a field in Cass County were observed showing classical symptoms of infection by Sclerotinia sclerotiorum. Plants in advanced stages of infection were dead. Stems of dead plants peeled off easily when touched and numerous cylindrical, black sclerotia that were 2 to 3 mm in diameter and 4 to 7 mm long were found in the pith. Younger stem lesions were watery soft, many of them with a white cottony growth on them. Sclerotia and infected stem tissues collected from the field were surface disinfested in a 0.5% NaOCl solution for 30 s, rinsed with sterile distilled water, and air dried before plating on potato dextrose agar (PDA). Samples were incubated at room temperature for 1 week. White mycelium and black sclerotia, characteristic of S. sclerotiorum (Lib.) de Bary, were produced in all dishes. Koch'...