POLYOL CONTENT OF BOSTRYCHIA AND STICTOSIPHONIA (RHODOMELACEAE, RHODOPHYTA) FROM FIELD AND CULTURE

Field and culture samples of Bostrychia and Stictosiphonia species were analyzed for D-dulcitol and D-sorbitol that function as osmoregulatory solutes and photoassimilation products. Bostrychia bispora West et Zuccarello, B. calliptera (Montagne) Montagne, B. montagnei Harvey, B. moritziana (Sonder ex Kutzing) J. Agardh, B. pinnata J. Tanaka et Chihara, B. radicans (Montagne) Montagne, B. simpliciuscula Harvey ex J. Agardh and B. tenella (Lamouroux) J. Agardh contain both polyols, except for one isolate of B. radicans (2879/80/81) that contains only D-sorbitol. Bostrychia tenuissima King et Puttock and Stictosiphonia hookeri (Harvey) Hooker et Harvey and S. kelanensis (Grunow ex Post) King et Puttock contain only D-sorbitol. Polyol accumulation is greater in nutrient-stressed culture of B. moritziana than in nonstressed culture. In Stictosiphonia hookeri D-sorbitol accumulation is lower at 15-degrees-C than at 25-degrees-C. Generally, in all species, field samples have much lower polyol concentrations than culture samples.