Fungal parasites of the marine green algae, Cladophora and Rhizoclonium

Abstract

Diseases caused by three fungal parasites in the green algal genus @iCladophora@@ from the beaches of Goa and Lakshadweep islands in Arabian sea in India are described. These are caused by @iSirolpidium bryopsidis, Olpidium rostriferum@@ and @iLabyrinthula@@ sp. Algal species in the genus @iRhizoclonium@@ was also heavily parasitized by @iLabyrinthula@@ sp. A species of @iCoenomyces@@ was found to be associated with @iCladophora repens@@ and @iRhizoclonium@@. The maximum occurrence of these fungi was found to be between July and September which is also the monsoon period in the western coast of India. Optimum salinity for maximum infection to occur under laboratory conditions was found to be between 10 and 15 ppt. Except @iLabyrinthula@@, the other fungi could not be cultured on artificial media. The species of @iLabyrinthula@@ required cholesterol (0.001%) for growth on artificial medium. Most of these parasites were host specific and they could not be cross inoculated on other algae or even other species of @iCladophora@@