The carbohydrates of bryophytes in relation to desiccation tolerance

Abstract

The major soluble carbohydrate in shoots of the mosses Dicranum majus, Hookeria lucens, Polytrichum commune, Racomitrium lanuginosum, Thuidium tamariscinum and Tortula ruraliformis is sucrose, whose content varied between 100 and 500 f.Lmolg dry weight−1. Sucrose content was unaffected by desiccation. Glucose and fructose are present at less than one-tenth the sucrose cop.tent in each species and, in T. ruraliformis, desiccation causes a decrease in their concentration. Comparison with published data suggests that the above features, along with low levels of starch, are characteristic of mosses. It is suggested that high sucrose content, allied with low levels of reducing sugars, contributes to the desiccation tolerance of mosses.