Phytophthora blight is one of the most serious threats to production of oriental melon in Guangxi province recently. It usually reduces the quality and yield of oriental melon. In this study,the causal organism of oriental melon blight was identified by pathogenicity,morphology and ribosomal DNA-ITS. The results showed that the isolated fungus was used for infecting healthy oriental melon fruit. Disease symptoms after inoculation were the same as that on the collected samples,which showed the fungus was the...