The Occurrence of Laminarionema elsbetiae (Phaeophyceae) on Rhodymenia pseudopalmata (Rhodophyta) from the Patagonian Coasts of Argentina: Characteristics of the Relationship in Natural and Experimental Infections, and Morphology of the Epi-endophyte in Unialgal Free Cultures

• DOI: 10.4490/algae.2009.24.4.249
• Publication Date: 2010-02-17T02:38:38Z
• Authors: M. Cecilia Gauna; Elisa R. Parodi; Eduardo J. Caceres
• Keywords: Endophyte; Morphology

The occurrence of Laminarionema elsbetiae (Ectocarpaceae, Phaeophyceae), as epi-endophyte Rhodymenia pseudopalmata (Rhodymeniales, Rhodophyta), described from Santa Isabel, Rawson, Argentina.L. grows in the host tissues forming epi-endophytic relationship epidermal, cortical and medullar layers.Epiphytic thalli L. were unbranched filaments emerging hostís surface.Reproductive structures on absent.On contrary, free cultured individuals formed different reproductive structures.Macrozoosporangia containing a single large motile zoospore originated vegetative cells, they conical to cylindrical shape, 30-50 µm length 18-20 wide.Uniseriate plurilocular zoosporangia 40 10-13 wide.Sexual fusion was not seen.In mixed cultures with R. fronds, infected host, grew natural and, macrosporangia between subcortical cells.Gametophytes diffuse growth, branched branch pattern alternate or opposite.Gametangia plurilocular, uni biseriate lateral.When mature contained 2 6 isogametes.The presence could be defined an relationship.The percentage infection by 34%.A 25% presented low, non-symptomatic level infection, whereas 62% 13% them exhibited respectively moderate high indexes infection.