Abstract
The Rf32 strain isolated from Rhododendorn formosanum was demonstrated to be a species
of Cryptosporiopsis (Dermateaceae, Helotiales) of ericoid mycorrhizal fungi (ERMF), and has the
ability to decompose organic matter. This study further documented the symbiotic ability of the
Rf32 fungal strain in association with 5 Rhododendron species. Inoculation results revealed that
Cryptosporiopsis sp. Rf32-inoculated Rhododendron seedlings all grew vigorously, and the hyphal
complex was found in cortical cells of root associations. This study demonstrated that Cryptosporiopsis sp. had symbiotic ability with R. mucronatum cv. Akemono, R. scabrum, R. kanehirai, R. ellipticum, and R. rubropilosum Hayata var. rubropilosum, and could form ericoid mycorrhiza in vitro with these Rhododendron seedlings.