Abstract:
In this study, the ability of Nepeta cataria L. to grow and synthesize bioactive compounds on
soil treated with different salt concentrations was tested to evaluate the opportunity of cultivating
it in soils affected by salinization. N. cataria L. was grown in soil containing specific amounts of
NaCl, Na2SO4, and their mixture. After harvesting, the plants were analyzed from the morphological
and physiological point of view. Salinity stress inhibited the growth, with the highest decrease of
the plant yield up to about 70% in the case of salt mixture, and smaller values for the separate salt
treatments. In the same time, as a defense mechanism, there was an increase of granular trichomes’
density, as observed with the scanning electron microscope. For mild concentrations of salt, the
amount of chlorophyll pigments was enhanced, while for stronger salinity stress, it decreased. The
opposite behavior was evidenced for the polyphenol content, as antioxidant activity was used as a
protective mechanism against reactive oxygen species produced under salinity stress. The antioxidant
activity was considerably higher for separate NaCl and Na2SO4 treatments than for the salt mixture
variants. The results showed that the species Nepeta cataria L. reacts well to high salinity levels, with
an increased content of bioactive compounds and antioxidant activity even for the highest studied
salinity conditions.
