1. CNRS-Université Pierre et Marie Curie, UMR 7139 Marine Plants and Biomolecules (A.L.B., B.B., N.K., M.G., S.S., D.S., J.M.C., B.C.), and Platform of Cytology, CNRS FR2424 (S.L.P.), Station Biologique de Roscoff, 29682 Roscoff cedex, France; Department of Forest Genetics and Plant Physiology, Umeå Plant Science Centre, Swedish University for Agricultural Sciences, S–901 83 Umea, Sweden (M.K., K.L.