Primi dati sulla distribuzione di batteri luminosi nel lago di Ganzirri (Messina)

The luminous bacteria present in the water column (free-living bacteria) are frequently isolated by several Authors from various habitats; nevertheless, their ecological role remains unknown. The taxonomy of luminous bacteria comprises the following species: Vibrio harveyi, Photobacterium phosphoreumn, Photobacterium leiognathi and Vibrio fischeri. In this study we reported the preliminary results of a research carried out on the spatial and temporal distribution of the luminous bacteria present in the brackish waters of the Ganzirri lake (ME). The numerical estimation on SWC Agar and the taxonomical identification of this bacterial aerobic flora, on the basis of the physiological and diagnostical criteria, were undertaken in order to register variations in the quantitative and qualitative distribution of various species. Among the 200 strains isolated, 75% were V. harveyi; this species occurs in environments with higher temperatures, whereas strains of Photobacterium are prevalent in the winter months.