Characteristics of Diatom Communities Epiphytic on Brown Algae Padinagymnospora (Kutzing) Sonder, from Central West Coast of India

Epiphytic diatoms among marine microalgae are of special interest for their environmental, biochemical and biotechnological applications. However, seaweeds particularly from the tropics have remained unexplored for their epiphytic flora. Diatom flora associated with Padina gymnospora were evaluated for their community structure. Diatom communities were highly diversified and were represented by 53 species, observing dominant genera Navicula, Rhizosolenia, Nitzschia, Grammatophora and Caloneis from relatively less or non-polluted localities. Composition from polluted areas typically supported one community hypothesis, with dominance of Biddulphia and Licmophora. Species diversity was found to be inversely related with nutrient concentrations in ambient waters. The present study proved that epiphytic diatoms on seaweeds could serve as reliable ecological indicators.