Genetic Manipulation and Strain Improvement in Commercially Valuable Red Seaweeds

Abstract

Over the past twenty years, seaweed cultivation has advanced to a level where there is hardly a single commercially valuable species that isn’t currently being cultivated. The largest cultivation industries for red seaweeds include the production of carrageenans from Eucheuma and Kappaphycus,of agar from Gracilaria and, the largest of all, the production of Porphyra or nori. In most of these cases, future improvements in production will most likely depend more on improving the suitability of the species being cultured than improvements in culture methods. Seaweed strain improvement efforts have traditionally relied upon classical plant breeding techniques (for reviews, see Cheney, 1990; Patwary and van der Meer, 1992), with the single most commonly used method being simple strain selection of wild plants or of new genetic variants produced by mutagenesis, colchicine treatment, and to a lesser extent, the use sexual hybridization. Sexual hybridization hasn’t had much impact with commercially valuable red algae because it has been generally impractical or impossible in most commercially valuable red seaweed (see Cheney, 1990).