Field and Laboratory Studies on some Photosynthetic Bacteria in Aswan High Dam Lake. II. Isolation and Identification of Purple Non-sulfur Bacteria (Rhodospirillaceae)

485 isolates were recorded from different localities between summer 1984 and spring 1985. These isolates comprise five different genera with eight different species of purple non-sulfur bacteria- Rhodopseudomonas was the most common genus at all sites and was represented by three species. R. acidophila, R. blastica, R. palustris. Rhodomicrobium was the second in frequency and was represented by R. vannielli only. This species was only recorded for khor sites. Rhodocyclus was represented by two species, R. gelatinosus and R. tenuis. Rhodobacter and Rhodospirillum were represented by one species each, Rhodobacter capsulatus and Rhodospirillum rubrum. Khor sites were richer in number of isolates and genera of purple non-sulphur bacteria than the main body of AHDL. Some species were more common in winter and spring while others predominate in summer and autumn.