PHYTOCHROME‐MEDIATED STIPE ELONGATION IN THE KELP <i>NEREOCYSTIS</i> (PHAEOPHYCEAE)¹

Abstract

ABSTRACT Preliminary evidence is presented which indicates that far‐red irradiation promotes and near‐red inhibits rapid stipe elongation in Nereocystis luetkeana (Mertens) Postels &amp; Ruprecht. Laboratory results showed afar‐red reversal of red inhibition, but a red/far‐red reversal was not evident in field experiments. The effects of changing ratios of red and far‐red irradiation brought about by selective water absorption are discussed in relation to stipe elongation of Nereocystis .