Concepts and issues of population genetics in seaweeds

The aim of this paper is to highlight the questions raised by a population genetics approach in order to discuss them in the context of seaweed popula tions studies. First, basic concepts of population genetics and their appli cation in conservation biology are briefly reviewed. Second, we rapidly sur vey the methods for analysing the genetic structure of populations : these methods estimate parameters that characterise mating systems, quantify gene flow and evaluate genetic drift. To illustrate these points, examples take n from studies on algal populations are presented and discussed.