engleski

Effects of aluminium and norflurazon on isolated algae from green hydra (Hydra viridissima Pallas) and related free-living species

Green hydra (Hydra viridissima Pallas, 1766) is a fine classical example of endosymbiotic organism. In its gastrodermal myoepithelial cells it contains unicellular photoautotrophic algae. Microalgae have a significant role as primary producers in aquatic ecosystems and are the basis of many food chains. For the first time performed was test of comparative toxicity of aluminium and norflurazon on isolated algae from green hydra, Desmodesmus subspicatus (Chodat) Hegewald et Schmidt and Mychonastes homosphaera (Skuja) Kalina et Puncochárová, which belong to the group Chlorella zagrebiensis Kovac. et Jelen. and on related free-living species Chlorella kessleri Fott et Novak. [K&H, 1992] strain LARG/1 and Chlorella vulgaris Beij. [K&H, 1992] strain SAG 211 - 11b. From evolutionary and ecotoxicological point of view, researched were cell viability, division, shape and size, level of damage, chloroplast fragmentation, intensity of green color, in relation to the concentrations of toxicants used in the experiment, by use of Chlorella test, light microscopy and morphometry. Today it is known that algal endosymbiotic partner from green hydra can be maintained in a permanent stable lab culture, so the special attention was pointed towards researching the differences between viability of isolated endosymbionts and their free-living relatives. The algae isolated from green hydra survived to the less extent the unfavorable conditions of the microenvironment than their free-living relatives, which showed greater viability and lower level of damages. It seems that separation of endosymbiotic partners left trace on the viability of isolated species. Once isolated, former endosymbiotic algal partner is less adapted to the new microenvironment than its free-living relatives.

symbiosis; algae; green hydra; ecotoxicology

Na kongresu sam sudjelovao i u sekciji Interactive workshop/sharing of living symbiotic systems with experts s izuzetno uspješnom i posjećenom radionicom Hydra symbiosis.