Anthracnose of genus Mandevilla caused by Colletotrichum truncatum and C. siamense in Japan

In 2009, leaf spots on Mandevilla ornamental cultivars Alice Delight and Sun Parasol Milky Pink were found for the first time in Kanagawa Prefecture in Japan. Pathogens isolated from the cultivars were identified as Colletotrichum truncatum and C. siamense based on morphology and molecular data. They reproduced original symptoms on each cultivar after inoculations and were reisolated. Both pathogens were also pathogenic to both cultivars. We propose calling the disease anthracnose, “tanso-byo” in Japanese.