Effect of Salinity on Osmotic Adjustment, Yield and Essence of Local Landraces Ajowan (Trachyspermum ammi L)

Ajowan is one of the most important medicinal plants in Zahedan region. Salinity and drought are the main causes of yield reduction of plants in Sistan and Balochestan. To evaluate the effect of salinity on yield and quality of ajowan a factorial experiment with randomized complete block design with three replications was conducted at the greenhouse of the Payam Noor University of Agriculture in Zahedan in 2016. Treatments were two populations of ajowan: C1: local and C2: Pakistani which were considered as the first factor and five salinity levels 0, 2, 4, 6 and 8 d/ms as the second. The results of this experiment showed that highest root length, stem height, plant fresh weight and plant dry weight and yield of essence belonged to local population under saline condition. Increasing salinity levels beyond 4 ds/ms decreased quantitative traits significantly but increased essential oil content and concentrations of osmotic regulants (prolin and carbohydrate) as compared to that of control. This may indicate that ajowan is tolerant to salinity.