New geographic distribution records and assumed microcyclic life cycle of Triphragmiopsis jeffersoniae (Pucciniales)

Triphragmiopsis jeffersoniae was found on Jeffersonia dubia in Sapporo, Japan, in 2003. This was the first geographic distribution record of the fungus out of its native distribution range in continental Far East Asia. This fungus was found also in Nikko, Japan, in 2011. Triphragmiopsis jeffersoniae formed Aecidium-type sori and tripartite teliospores subtended by a pedicel. In the early spring, the fungus formed telia with or without Aecidium-type sori on petioles of emerging host leaves. Subsequently clusters of Aecidium-type sori were formed on the abaxial leaf surface. These sori did not repeat; but they were soon densely surrounded by telia. Both the Aecidium-type sori and telia were densely crowded and no small isolated telia were formed. The assumption that the spores from Aecidium-type sori do not have infective ability was confirmed by inoculation experiments and microscopic observations for the Japanese materials. The Aecidium-type spore germlings failed to invade the Jeffersonia leaf either directly or through a stoma under the experimental conditions. Thus, T. jeffersoniae was assumed to have microcyclic life cycle, comprising the functional teliospores and the non-functional Aecidium-type aeciospores.