بررسی تأثیر تنش شوری بر خصوصیات رشد ومیزان تجمع یونی در گیاه اشنان

The effect of salt stress on the growth and ion accumulation in Seidlitzia rosmarinuswas determined by growing plants in soils receiving different percentages of a composed salt. Saltwort (S. rosmarinus) plantswere grown under controlled greenhouse conditions. Growth parameters were progressively declined by increasing soil salinity percentage. Saltwort, a perennial halophyte, exhibits significant reduction in height and biomass under saline stress conditions. Leaf sodium (Na+) content increased when plants were subjected to saline conditions. Such a trend was also observed for color anion (Cl-). On the contrary cations such as Ca+, Mg+ and K+ decreased with increasing in soil salt content. Low levels of salinity (0.25 and 0.5% salt kg dry soil) did not cause substantial inhibition of growth (root and stem) but increasing concentrations of salt induced a progressive decline in fresh and dry weights of the plants. Salt stress induced a significant decrease in leaf (fresh and dry) weight. Significant effects of salinity stress on K+ and Mg+ were not found in roots. Another possible conclusion is that improved tolerance to salt stress may be accomplished by alteration in growth parameters and ion accumulation. Based on achieved findings the tolerant saltwort can be grown in moderately saline soils.