The first report of brown root rot disease caused by Phellinus noxius on Reevesia formosana which raises concerns on the conservation of R. formosana and Formotosena seebohmi (Hemiptera: Cicadoidea) in Taiwan

The first report of brown root rot disease caused by Phellinus noxius on Reevesia formosana which raises concerns on the conservation of R. formosana and Formotosena seebohmi (Hemiptera: Cicadoidea) in Taiwan

Brown root rot disease on Reevesia formosana was firstly found in Chiayi County, Taiwan. The infected trees with foliage wilting, leaf discoloration, brown mycelial mat on root and basal stem, and brown mycelial networks in rotten diseased wood were observed. The infected trees wilted eventually. Phellinus noxius was identified as the causal pathogen by the symptoms and signs shown on the trees. Also, morphological and molecular identification of the fungal colony isolated from the diseased tissue was carried out. P. noxius was inoculated to 6-year-old R. formosana seedlings with P. noxius grown on the oat grain medium in the greenhouse. Inoculated seedlings were infected. The symptoms and signs shown on the seedlings were the same as in the field. The fungus was then re-isolated from the diseased tissue. This is the first report of P. noxius on the host R. formosana in Taiwan. Since R. formosana is the main food source of Formotosena seebohmi, the outbreak of brown root rot disease on R. formosana deteriorates the habitat of F. seebohmi and may threaten the population of F. seebohmi when no proper mitigation is applied.