Effect of Salinity and Heat Stresses on Rosmarinic Acid Content and Gene Expression in Peppermint (Mentha piperita L.)

Rosmarinic acid (RA) is a valuable medicinal compound which can be produce through the phenil propanoid biosynthesis pathway. An experiment was carried out in order to study the effect of three levels of salinity (۰, ۶۰ and ۱۲۰ mM of sodium chloride) and two levels of thermal stresses (۲۵°C and ۳۵°C) on Rosmarinic Acid Content and expression of RAS gene in Mentha piperita L. in a completely randomized design with three replications. The result showed that the temperature, salinity, time, and their interaction had significant effects on changes in the levels of Rosmarinic Acid Content and expression of RAS gene at a ۱% level (P ≤ ۰.۰۱), the Rosmarinic Acid Content and expression of RAS gene decreased with increasing temperature and salinity. The comparison of the corresponding treatments between ۲۵˚C and ۳۵˚C indicated that the simultaneous effect of salinity and temperature compared to the salinity stress resulted in a smaller reduction in the amount of rosmarinic acid.

Keywords:

medicinal plant , Mentha piperita L. , salinity , heat , real-time , Rosmarinic Acid.