| Abstract: | The method is based on the determination of the number of the nonmotile sperms and/or the lethally damaged sperms with the aid of the fluorescent dye primuline. Incubation takes place at a suspension density of 10.000/mm3… 38.000/mm3, at 40°C or 46 °C for 15… 60 min. During the test with sublimate the loss of motility amounts to 55% at 4 mg/l Hg2+, the LC50 is 7.3 mg/l Hg2+. Phenyl-mercuric acetate causes the total loss of motility with 20 mg/l, the LC50 is above 168 mg/l (equivalent to 100 mg/l Hg2+). The LC50 of sodiumpentadecylmonosulphonate and dodecylpyridinchloride are 11.6 and 15.8 mg/l, resp. Filtrates of blooming of cyanophyceae on Baltic, having been digested by repeated freezing and thawing, with 1.5… 6.4 g/l dry matter showed motility losses of 30… 100 % for Nodularia spumigena, whereas no significant effect was produced by a filtrate of Microcystis aeruginosa with 28.2 g/l dry matter as well as water-blooming of Nodularia spumigena from the Small Jasmund Bodden. |
