Wound response and regeneration in Coelarthrum opuntia

Coelarthrum opuntia (Rhodophyta) is frequently wounded by epiphytic growth, herbivore-attack and/or wave-action. Wound-repair involved cell divisions in the cortical region just below the wound-site to form a mass of cells. T he wound-site was veneered by a thick and protective extracellular mucilagi nous cover rich in carboxylated and sulphated polysaccharides. Medullary ti ssue contributed to regeneration of new fronds identical to those of the pa rent thallus. Regeneration capacity was higher in the apical regions wherea s the lower internodal regions revealed proliferation in response to woundi ng. (C) 2000 Elsevier Science B.V. All rights reserved.