Abstract
A description is provided for Phacidiopycnis tl jberivora. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Solanum tuberosum, Alnus, Beta, Escallonia, Eucalyptus, Hoya, Humulus, Medicago, Olearia, Ribes, Syringa, Vaccinium and probably several other plants. DISEASE: Stem-end hard rot or progressive dry rot, or corky rot of potatoes (11, 671; Foster & Macleod, 1932). Symptoms are variable; on mature tubers lesions vary in size from pin heads to those involving the whole tuber. With the progress of infection lesions become sunken, circular with a well defined margin. When immature tubers become infected they become mummified (Foster & Macleod, 1932). GEOGRAPHICAL DISTRIBUTION: Asia (India); Australasia and Oceania (Australia, New South Wales, New Zealand); Europe (UK); North America (Canada, Alberta, Vancouver, British Columbia; USA, Washington). TRANSMISSION: No specific studies reported. Probably by conidia discharged during alternating dry and wet conditions; penetration of tubers through wounds and abrasions.