Puccinia velutina: A New Caricicolous Rust and a Perfect State of Aecidium elaeagni

Reciprocal inoculations with basidiospores and aeciospores proved that the telial host of Aecidium elaeagni on Elaeagnus species is Carex lenta. Comparative morphology with other caricicolous rusts shows that the rust fungus is new. We name it Puccinia velutina Four Aecidium species parasitic on Elaeagnus were reported in Japan (Ito, 1950; Hiratsuka, 1960). We found Aecidium elaeagni Diet. on Elaeagnus glabra Thunb. at Mt. Tsukuba, Ibaraki, Japan. It was described on E. pungens Thunb. (Dietel, 1898), and is widely distributed in Japan, except Hokkaido, and in Taiwan (Ito, 1950; Hiratsuka, 1960). This rust has been considered as the spermogonial and aecial stage of Puccinia coronata Corda. We therefore collected teliospores of P. coronata on Calamagrostis arundinacea (L.) Roth var. brachytricha (Steud.) Hack. and Brachypodium sylvaticum (Huds.) Beauv. at Mt. Tsukuba, and inoculated Elaeagnus species with basidiospores from teliospores of P. coronata from these collections. However, results were negative. In 1979, we found the telial stage of Puccinia sp. on Carex lenta D. Don near Aecidium-infected E. glabra, and suspected a genetic relation between the rusts on E. glabra and C. lenta. We report here the results of reciprocal inoculations and morphological observations of the rusts, and discuss their taxonomy. INOCULATION EXPERIMENTS