Effect of NaCl on chlorophyll and protein content, and antioxidant enzymes activity in two bryophyte species – Atrichum undulatum (Hedw.) P. Beauv. and Marchantia polymorpha L.

Abstract

Bryophytes are thought to avoid salty substrates, although in few species reported salt tolerance is greater than in non-halophyte tracheophytes. To explore bryophyte salinity tolerance, two species were grown in vitro on half-strenght MS media with added NaCl (concentrations of 100, 250 and 500 mM). Chlorophyll content was measured spectrophotometrically, and protein content, peroxidase and catalase activities were assayed both spectrophotometrically and by PAGE. Chlorophyll content in M. polymorpha decreases rapidly with rising salt concentrations approaching zero at 250 mM, while in A. undulatum it remains high at 100 mM of salt above which decreases. Protein content remains high at 100 mM of salt in both species and decreases at higher salt concentrations (in M. polymorpha several times compared to control values). Peroxidase activity is much higher in M. polymorpha and decreases slightly at high salt concentrations. Catalase activity in A.undulatum remains high at all salt concentrations, in contrast with M. polymorpha whose activity lowers considerably at 250 mM of salt.