Histological studies on the genus Fucus. IV. Regeneration and adventive embryony

Abstract

Regeneration in Fucus vesiculosus L., both under natural conditions and in culture, has been studied histologically.Cut segments of vegetative tissue from mature Fucus specimens were cultured in seawater. Histological sections of this material were prepared at various intervals up to 8 months of culture to follow the development of adventitious branches from the wound surfaces. In both cultured segments and whole, naturally wounded plants, existing filament and cortical cells in the midrib region of wound surfaces differentiate a new epidermis. Several loci on this new epidermis undergo increased rates of periclinal division to produce structures which are morphologically very similar to normal Fucus embryos and which ultimately acquire apical grooves and apical cells and become flattened in the manner of normal vegetative thallus branches. The significance of the wound-healing process and the formation of adventive embryos is discussed.