STUDIES ON THE PHOTOBIOLOGY OF <i>BANGIA FUSCOPURPUREA</i>¹

Abstract

SUMMARY In the Rhodophyta there are few reports of light‐mediated responses. In Bangia fuscopurpurea the formation of the fertile cell rows by the Conchocelis phase meets criteria established for the definition of photoperiodism in higher plants. Throughout the life history of the alga maintained in culture, cell fate and cell function fire under photoperiodic regulation. Maintenance and conversion photoperiods are established. Sequential induction studies suggest the absence of metabolic effects operative in the induction, response of fertile cell row formation. Preliminary studies of non‐24‐hr photoperiods suggest the absence of short‐term endogenous rhythms involved in spore formation. A phytochrome response involved in the formation of the fertile cell rows is demonstrated.