Effects of daylength and irradiance on the formation of reproductive organs in two algae: acrosymphyton purpuriferum (J.Ag.) Sjöst. (Rhodophyceae) and Sphacelaria Rigidula Kütz. (Phaephyceae)

This thesis deals with effects of daylength and irradiance on the formation of reproductive organs in two algal species: the red alga Acrosymphyton purpuriferum (J.Ag.) Sjöst. and the brown alga Sphacelaria rigidula Kütz. Acrosymphyton is a shortday plant for the formation of its tetrasporangia, Sphacelaria is a long-day plant for the formation of its gametangia. The general introduction states the criteria for identification of a genuine photoperiodic response, it reviews the photoperiodic responsed known in red and brown algae an it summarizes the data on environmental regulation of the life histories of Acrosymphyton and Sphacelaria. ... Zie: Summary Zie: summary.