The life cycle of Gyrodinium instriatum (Dinophyceae) in culture

摘要: SUMMARY The life cycle events of an unarmored dinoflagellate Gyrodinium instriatum Freudenthal et Lee has been investigated using clonal cultures. After the inoculation vegetative cells into fresh medium, clumping gametes was observed after a period 10 days. In clumps, number were to be swimming in close contact with each other, pairing successively and then forming plano-zygote. This behavior is considered useful performance sexual reproduction, particularly event low cell density, because it increases chance fusion. Gametes this species most often isogarnous, although apparent amsogamous fusions occasionally observed. When planozygotes isolated placed they enlarged their size finally divided two cells. The daughter continued multiply by binary fission produced Thus, G. alternative between zygotes without hypnozygote stage. However, cysts transformed from large motile (pre-cyst cells) which are oblong dorso-ventrally flattened shape. These mottle pre-cyst have longitudinal flagella, may indicate that zygote origin. On basis these results, relationship pre-cysts discussed. Excystment enhanced dark cold treatments prior incubation for germination experiments success rate 26–64%. Encystment greatly inhibited lack treatments.