Response of coriander to salinity stress

Salinity in the soil and irrigation water is an environmental problem and a major constraint for crop production. Coriandrum sativum as a leafy vegetable is great interest for vegetable producers in the world. However, due to gradual increase in soil and water salinity, especially in Northwest Iran, the production of this vegetable has been faced with many constraints. This experiment was conducted to study the effect of salinity on some morphological and physiological traits of Coriandrum sativum. The factors were arranged as factorial based on randomized complete block design with five NaCl levels (0, 50, 100, 150 and 200 mM NaCl) and local ecotypes (Tabriz, Malayer) with three replications. The results revealed that there was interaction of salinity levels with ecotypes in terms of proline content and relative water content. The highest amounts for proline content (77 μg^-1 FWt) was recorded for Tabriz clone under 200 mM NaCl. The greatest relative water content was obtained by Tabriz clone × NaCl 0 and Malayer × NaCl 0 and 50 mM combinations. The highest dry weight of leaves, K^+/Na^+ ratio and K^+ belonged to the non-salinity condition. Highest amounts of Na^+ accumulation, MDA and H2O2 level and ion leakage were attained with 200 mM NaCl level. Soluble sugars content were affected by both salinity and ecotype. The highest content of soluble sugars was achieved by Malayer ecotype. With increasing salinity level, the content of soluble sugars increased and the highest amount of soluble sugars content was recorded at 200 mM NaCl.