Yeast communities associated with different plant resources in sandy coastal plains of southeastern Brazil

Abstract

The distribution of yeasts was studied in different plant substrata of beach and restinga ecosystems in southeastern Brazil. Candida sonorensis, Clavispora opuntiae, Pichia barkeri, Pichia cactophila and Geotrichum sp. were generally prevalent in yeast communities associated with necrotic tissues of the cacti Cereus pernambucensis, Selenicereus rizzini, Opuntia vulgaris and Opuntia sp. Cactus yeast communities were unique and no cactophilic yeast species were isolated from plant substrata other than cacti in these ecosystems. Flowers of the cactus Cereus pernambucensis had a highly specific yeast community composed almost exclusively of Pichia sp. C, a Candida domercqii -like species and Candida sp. C. Flowers of Ipomoea litoralis and Ipomoea pes-caprae , and extrafloral nectaries of Senna australis and Senna bicapsularis had communities composed predominantly of basidiomycetous yeast anamorphs. Insect vectors, the chemistry of each plant resource, and environmental conditions of these microhabitats are among the most important factors determining the species composition of these communities.