Resumo

MORALES, Eduardo A. et al. Hypothesis: the union Microcystis aeruginosa Kütz.-Nitzschia palea (Kütz.) W. Sm.-bacteria in Alalay Pond, Cochabamba, Bolivia is symbiotic. RevActaNova. [online]. 2015, vol.7, n.2, pp. 122-142. ISSN 1683-0789.

A bloom of Microcystis aeruginosa Kütz. is reported from the plankton of Alalay Pond, a brackish, urban and highly eutrophic ecosystem. The cyanobacterial colonies were in turn colonized by the diatom Nitzschia palea (Kütz.) W. Sm. This co-occurrence has been previously reported only twice in the literature. As part of the grouping, pleomorphic bacteria were also observed, but their identity could not be established. Field and laboratory observations, as well as a literature revision, suggest that the association of the three types of organisms is symbiotic, assuring a continuous supply of nutrients of exogenous and endogenous origin. Besides obtaining nutrients, Nitzschia palea also benefits from suspension in the upper part of the photic zone, where availability of light and nutrients is higher. In this manuscript, diverse arguments to support the symbiosis hypothesis are explored as a first step towards the physiological and molecular investigation of the association.

Palavras-chave : Bacillariophyta; contamination; Cyanobacteria; eutrophy; plankton; Sphingomonadales; urban pond.