Salinity Impact on Growth, Essential Oil Content and Composition of Coriander (Coriandrum sativum L.) Stems and Leaves

The influence of salt stress on vegetative growth, essential oil content, and composition of Tunisian coriander (Coriandrum sativum L.) grown in hydroponic culture was investigated. The volatile constituents of stems and leaves were isolated by hydrodistillation and analyzed by GC and GC/MS. Seedlings were treated with different levels of salt stress (25 mM, 50 mM and 75 mM NaCl). Results showed that the stein and leaf biomasses were not affected Under 25 mM NaCl, compared to the control, although it decreased significantly at 50 mM and 75 mM. Essential oil content was 1762.64 mu g/g DW (0.18%) and 1255.77 mu g/g DW (0.12%) in stems and leaves, respectively. At low and moderate stress, a significant difference in the essential oil content was developed between sterns, with a significant decrease, and leaves, with an increase up to 43%. Under high salinity, the oil content of both organs decreased significantly. The major volatile compound of stems and leaves was (E)-2-decenal with 24% and 52%, respectively. Other important components were decanal, (E)-2-dodecenal, dodecanal, (E)-2-undecenal, (E)-2-tridecenal and (E)-2-undecanal. Further, the content of these compounds were affected differently by the treatment level and by the organ type.