Effects of Light Intensity and NaCl Salinity on Yield and Uptake of Some Elements in French Tarragon (Artemisia dracunculus L.)

Salinity is the most important factor limiting plant growth; light intensity is also a prominent factor affecting the response of plants to salinity stress. In order to investigate the effects of light intensity and salinity on yield and concentrations of some elements of tarragon plant, an experiment was carried out. The experiment was laid out in split plots with a randomized complete blocks design at 4 replications in soilless culture. Treatments consisted of two light intensities as main plots and five NaCl levels (0, 20, 40, 60 and 80 mM) as subplots. At the beginning of flowering, plants were harvested and shoot fresh and dry weights and elements concentrations were measured. The results showed that the salinity increase and in light intensity decrease led to shoot fresh yield and dry weight decrease. With increase of salinity more than 20 mM sodium chloride in solution, sodium concentration in leaves increased and this increment in shade was more than that in full light conditions. In the shadow conditions, first, increasing salinity caused K+ concentration to remain constant; then it decreased. Salinity reduced leaf nitrogen concentration, which was more pronounced in lower light conditions. Leaf P concentration was reduced under saline conditions. Salinity levels higher than 20 mM led to leaf calcium concentration to be reduced.