A root rot disease on pansy geranium (Pelargonium tricolor × P. ovale ssp. ovale ‘Splendide’) was found in Shizuoka Prefecture, Japan in June 2003. A fungus was isolated and used to inoculate cuttings to reproduce the root rot symptoms. It was identified as Thielaviopsis basicola. This disease is the first record in Japan and is named black root rot (Kurone-byo) on pansy geranium.
