The study investigates the effect of cadmium (Cd), salinity (NaCl), and combined stress on rhizosphere pH, growth parameters, membrane leakage, and genotoxicity in Vicia faba. Germinated seeds were exposed for 48 h to 0.01 mM Cd(NO3)2 (Cd), 50 mM NaCl (S50), 150 mM NaCl (S150), and Cd-NaCl (CdS50 and CdS150). An accumulation of Cd and Na was found essentially in Vicia roots under each single stress factor associated with variations in rhizosphere pH. Additional NaCl in metallic solution significantly dropped the rhizosphere pH and decreased Cd concentrations in roots by 2.3 and 3.8 times for CdS50 and CdS150, respectively. Growth parameters (root length and fresh and dry matters), mitotic activity, and micronucleus formation were not influenced by Cd and low concentration of NaCl when applied separately or together, while 150 mM of NaCl, alone or combined with Cd, affected negatively all the studied parameters, as well as chromosome and nucleus stability. V. faba seems to reduce the transport of Cd in saline conditions and therefore salinity (50 mM) may act as a protection against Cd accumulation.
Keywords: Cd; Combined stress; Genotoxicity; Growth parameters; Membrane permeability; NaCl; V. faba.