Sphenospora kevorkianii on the orchids Epidendrum paniculatum and Stanhopea graveolens newly reported in Argentina

Abstract

Plants of Epidendrum paniculatum and Stanhopea graveolens were collected in May 2007 as part of a native orchids preservation project in Baritú National Park, a protected area of the Yungas subtropical forest located in the province of Salta (Northwestern Argentina). The causal agent of the rust diseases was identified as Sphenospora kevorkianii. Urediniospores were ovoid yellowish and echinulate. The telia observed on E. paniculatum were subepidermal and erumpent, in which numerous clavate paraphyses were found besides the pedicelated teliospores, longitudinally one-septate, hyaline and thin walled. This is the first report of Sphenospora kevorkianii infecting E. paniculatum and S. graveolens in Argentina.