Salinity Stress Effect on Morphological and Physiological Properties in Giant Reed (Arundo donax L.)

Salinity is a significant abiotic stress factor that threatens agriculture in both arid and semiarid environments, affecting over 20% of the world’s irrigated land. In the present study, we have investigated that effects of different salinity levels (0, 50, 100, 150, 200, and 250 mM NaCl) in giant reed (Arundo donax L.). Salt treatment was started as 50 mM and this concentration was increased day after day, and finally 250 mM concentration of NaCl was applied until harvest time. Stress responses of the giant reed were measured in early plant development stage. In conclusion, the giant reed showed large variation in their response to salt tolerance in different salt levels. The morphological parameters were reduced with increasing salt concentrations; important decreases occurred with 100 mM NaCl and the lowest values were obtained with 250 mM. The highest 0-5 symptoms score were determined in 250 mM levels. The fresh and dry weight, fresh and dry root weight decreased 27-60% and 13-77% compared to control groups, respectively. While the relative water content was obtained 85% in control plants, this parameter decreased 52.5% ration in 250 mM salt level. The increasing salt stress caused decreasing in chlorophyll content. With increasing of salt levels, Na ion content increased on the other hand K and Ca ions contents diminished. The results obtained from this experiment show that high salinity reduced plant growth and development in giant reed. In these levels, 150 mM NaCl concentration was determined at critical dose for plant development