Phytochrome-mediated Induction of Phenylalanine Ammonia-Lyase in Mustard Seedlings: A Contribution to Eliminate Some Misconceptions.

The present report shows that the effect of red and far red light on the synthesis of phenylalanine ammonia-lyase can be ascribed to the action of phytochrome Pfr. This is true not only for short term irradiation but also for the action of continuous far red light. In the latter case, the model worked out by Hartmann implicating some excited species of phytochrome has to be taken into account.