Uredinales do Parque Ecológico Gunma, Município de Santa Bárbara, Pará, Brasil.

Abstract

Fungi of the order Uredinales are pathogens responsible for plant rusts, with about 130 genera and 6000 reported species. They affect a large number of host plants, causing varied symptoms such as leaf spots and pustules. They are pleomorphic pathogens, highly host-specific and obligate parasites. The present work aimed to collect and identify the rust specimens from Gunma Ecological Park. The study area is located in the municipality of Santa Bárbara (1°13'00.86 "S and 48°17'41.18 "W), Pará State, with an extension of 540 ha, and is considered to have a floristic richness that is very representative of the flora of eastern Amazonia. Ten collections were made in the period from June 23, 2005 to February 16, 2006. The collected material was pressed and dried for further identification. This step was based on the hosts, morphological analyses of fungal microstructures, specialized literature and comparisons with specimens deposited in the MG herbarium. For microscopic observations, semi-permanent slides of sera and spores were prepared, mounted in lactophenol solution and heated. Forty host plant specimens with rust were examined, classified in 18 genera and 14 plant families belonging to the Magnoliophyta division. In the studied specimens, 17 species of Uredinales were identified, classified in 6 families, representing 7 teleomorph genera: Puccinia, Uromyces, Chaconia, Cerotelium, Sphenospora, Porotenus and Coleosporium, and 2 anamorph genera: Uredo and Aecidium. The species Puccinia arechavaletae Spegazzini was the best represented, with 6 specimens identified, followed by Puccinia bambusarum Arthur (5), Puccinia heliconiae Arthur (5) and Chaconia sp. In this paper, the species Uredo philodendri Pardo-Cardona represents the first citation for Brazil. Descriptions, illustrations, identification key, incorporation in João Murça Pires herbarium (MG) and computerization in Brahms program were performed.