Effect of salinity on germination and seedling growth of Trigonella foenum-graecum, Dracocephalum moldavica, Satureja hortensis and Anethum graveolens

Abstract Salinization is increasing on a global scale, and tolerance to salinity during germination is critical for the establishment of plants and growing in saline soil. A laboratory experiment was carried out to assess the germination and early seedling growth response to salinity stress of four species, which are common medicinal species in Iran. Seeds of fenugreek ( Trigonella foenum-graecum L.), dragonhead ( Dracocephalum moldavica L.), savory ( Satureja hortensis L.), dill ( Anethum graveolens L.) were treated with various concentrations of NaCl (0, 40, 80, 120 and 160 mM L −1 ). In all species, an increasing NaCl concentration led to a decrease in germination and seedling growth, and maximum reduction was found at the highest salt level (160 mM L –1 ). All medicinal species were moderately tolerant to salinity up to 40 mM NaCl, but varied in degree of salt tolerance as salinity increased. Among four plant species, dragonhead has the most potential for successful germination and establishment in the saline environments.