Abstract
Phytophthora blight of southern star (Tweedia caerulea) occurred in Kanagawa Prefecture in September 2008. The causal agent was identified as Phytophthora citrophthora.
Phytophthora blight of southern star caused by P. palmivora already had been known. However, symptoms caused by these two pathogens were not distinguishable from each other. Therefore, P. citrophthora should be added as another causal agent of the disease in Japan.