A pot experiment based on complete block design was carried out to investigate the effect of salinity on growth traits and essential oil content of chamomile (Matricaria chamomilla L.). Four levels of salinity including control (0 mM), 50, 150 and 250 mM Nacl and CaCl2 in 5:1 molar ratio were used. Result indicated that increased salinity caused reduction in plant height, number of branches per plant, number of flowers per plant. Increased salinity also significantly decreased plant dry weight, flower dry weight and essential oil content. The highest values of growth traits such as number of flower per plant, flower dry weight and essential oil content were observed under control condition (non-salinity stress). The effect of salinity on flower dry weight is greater than other traits. Flower dry weight of plants at low (50mM) level of salinity was decreased 12.2% compared to control (non-stressed plant) while essential oil content increased 18.2% at the same salt concentration. At the highest level of salt stress (250mM) flower dry weight and essential oil content was decreased by 79.8 and 45.5% compared to non stressed plants, respectively. Number of flower per plant was decreased by 16.1 and 69.2% at lowest (50 mM) and highest (250 mM) salinity concentration respectively. Salinity affects flowering time of plants. Flowering time of non-stressed plants started 50 days after plant transplanting while flowering time of plants treated by 250 mM salinity started 64 days after seedlings transplanting to pots.

Keywords