Abstract A description is provided for Phytophthora erythroseptica . Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Potato, asparagus, cineraria, tomato, pea, raspberry, tulip, Zantedeschia , sugarcane, vetch. DISEASE: Pink rot of potato; shanking of tulip; rhizome rot and leaf blight of Zantedeschia ; sugarcane seed-piece rot; raspberry root rot; tomato buckeye rot. GEOGRAPHICAL DISTRIBUTION: Europe (UK, Irish Republic, Belgium, Bulgaria, France, Greece, Italy, Netherlands, Poland, Switzerland, USSR, Yugoslavia); Asia (India, Indonesia, Iran); Africa (Egypt); N. America (Canada, USA); Central America (Cuba); S. America (Venezuela, Peru); Australia; New Zealand. (CMI Map 83, ed. 4, 1973). TRANSMISSION: Soil-borne, oospores disseminated from diseased potato stems and roots persisting for many years. In the field tubers are generally infected through the stolon, but direct infection through eyes may occur in field and storage under moist conditions (13, 180; 19, 40). Transmission during storage, and survival of inoculum in apparently healthy tubers, was shown to be possible (57, 758). Tulip bulbs were invaded from the soil through the roots to the basal plate and flowering stem (18, 183).