The effect of drought stress on growth parameters, essential oil yield and constituent of Peppermint (Mentha piperita L.)

Abstract

5 Abstract: Peppermint (Mentha piperita L.) is one of the most important plants producing essential oil. An experiment was carried out using a randomized complete block design with 3 replications to study the effect of salinity stress on growth parameters, essential oil constituents and yield of peppermint. Full-strength Hoaglund's solution containing 0, 50, 100 and 150 mmol L NaCl was applied in irrigation plantings for 4 1 months in a greenhouse. The results showed that salinity stress significantly affected Stem length, root length, shoot wet weight, root wet weight and shoot dry weight, root dry weight, Internodes length, stolon length, biomass, Essential oil yield and Essential oil percent in P < 0.05. An increase in the salinity lead to reduce in length of stem and root, fresh weight of stem and root, dry weight of stem and root, internodes length, total biomass and essential oil percent and yield. It is necessary to mention that peppermint did not tolerate 150 mmol L NaCl and died under this condition. The highest values of growth parameters and essential 1 oil percent and yield were observed under non-salinity condition (control). Also, the highest values of Mentone were obtained under non-salinity condition (control) by using GC-MS.