No abstract

Salinity is a major factor limiting plant growth and crop productivity (Allakhverdiev et al. 2000). Salt damage to plants is produced by a combination of several causes, including mainly osmotic injury and specific ion toxicity (Munns et al. 1995) that affect a wide variety of physiological and metabolic processes in plants. Significant ABSTRACTCabbage seedlings were grown hydroponically to study the effects of different concentrations of seawater on the seedling growth, ion content under one-fourth strength Hoagland's nutrient solution in the greenhouse. The biomass of various organs of cabbage seedlings as well as the whole plants was significantly higher in the treatments with 1 g and 2 g sea salt/L than the no-salt control, but the treatments with 4, 5 or 6 g sea salt/L caused a decrease in growth. Root/shoot ratio remained at the level of control regardless of the sea salt treatment. Na + and Cl -concentration in different parts of cabbage seedlings increased significantly, whereas K + and Ca 2+ concentration generally increased at low concentrations of sea salt and then decreased with increasing seawater concentration. Sodium and K + concentrations were significantly higher in the stems than roots and leaves regardless of the sea salt treatment. The sea salt treatment increased Mg 2+ concentration in stems and leaves of cabbage seedlings. An increase in Na + and Cl -concentration in roots, stems and leaves of cabbage seedlings was the main contributor to declining ratios of K + /Na + , Ca 2+ /Na + and Mg 2+ /Na + . The obtained data suggest that cabbage seedlings have strong ability to sustain seawater stress by the regulation of transport and distribution of ions.