The Effect of Norflurazon on Green and Brown Hydra

Individuals of green (sort S1J-J1) and brown (sort S1M-K1) hydra were treated with five concentrations of aqueous solution of norflurazon (2x10-4, 2x10-5, 2x10-6, 2x10-7 and 2x10-8 mol/L; SAN 9789, Sandoz, Switzerland) in the laboratory conditions (21o C, photoperiod 10 hs daylight and 14 hs dark) in subacute exposure for 21 days. They were compared to the control groups of organisms. For morphological analysis binocular light microscope Carl Zeiss, Jena was used. For cyto-histological analysis hydras were fixed in Bouine fixative 24, 48 and 72 hs after the beginning of the experiment. Preparations were dyed with 0.1 % toluidine blue pH 4.4 and hämalaun-eosine (he). Micrographs were made by using Reichert and Nikon Eclipse E600 microscopes, Pentax and Nikon DXM1200 cameras.