In recent years, Yam black spot caused by Alternaria dioscoreae Vasant Rao became more prevalent throughout the hill yam growing area in the east part of Liaoning province, China. Study of biological characteristics of the pathogen showed that the optimal temperature and pH for its colony growth were 25-30℃ and 6-8 respectively; the optimal temperature, RH, pH and carbon source for conidium germination were 20-25℃,100%,6-7 and saccharose respectively. The conidium lethal temperature was 48℃.
