Cell and Tissue Journal

Abstract Aim: In this study, the effect of IAA on salt tolerance of tobacco plants (Nicotiana plumbaginifolia) was investigated under in vitro culture conditions.
Material and Methods: Sterile seeds of N. plumbaginifolia were cultured in MS medium. In vitro propagated seedlings under tissue culture conditions were treated with IAA (mg / l) and salinity (0, 100 and 200 mM) for 4 weeks. Physiological and biochemical parameters including H2O2, chlorophyll, soluble carbohydrate, protein and antioxidant enzyme activity were measured.
Results: Salt stress increased H2O2, proline, catalase, superoxide dismutase and ascorbate peroxidase, while reverse patterns were observed for photosynthetic pigments, soluble carbohydrates and also total protein.  In salt-treated seedlings, application of auxin increased proline, catalase and H2O2, but decreased photosynthetic pigmentation, soluble carbohydrates, total protein and some enzymes such as superoxide dismutase and ascorbate peroxidase.
Conclusion: Auxin treatment in salt-treated tobacco seedlings improved salinity tolerance by changes in some physiological parameters.
 
 

Abstract Aim: In this study we have used two wheat varieties with different tolerance to salt in different concentration of solt.
Material and Methods: Giza 168, Seds 1 plants have been grown for seven days in Hoagland solution and some of them were grown in Hoagland solution supplemented with 200 mM extra salt. Cutted leaf segments from these plants incubated with 600 mM salt. Dark-grown pre-adapted, with 200mM extra salt, plants were illuminated to determine the chlorophyll accumulation in two varieties.
Results: The maximum photochemical efficiency, Fv/Fm, stayed the same for all measurements. Measurement of relative ETR showed that the tolerant variety, Seds 1, had higher values for ETR than the susceptible variety (Giza 168). Also the measurement showed that the salt adapted samples of both varieties better withstood the excess of salt applied than the non-adapted samples.
The chlorophyll content was higher for the tolerant variety compared to the susceptible. The chlorophyll accumulation of the tolerant samples pre-adapted with or without salt showed no dramatic differences. The susceptible sample, Giza 168, however, accumulated more chlorophyll if pre-adapted to salt before being exposed to high salt concentration.
Conclusion: PSII seems to be stable and unaffected at the functional level by salt stress. The tolerant variety is better adapted to salt stress. It seems to be due to the advantage of having a more efficient photosynthetic apparatus.