Role of salicylic acid in amelioration of drought stress in Hibiscus sabdariffa

Stress is an external factor, which cause undesirable effects on plant. Plants are continuously exposed to different environmental stress under natural and agricultural conditions. Drought stress, also known as water stress, is a most important of environmental stress. Under unstable conditions, endogenous defense systems may not be enough to cope with the stress. Thus, signal molecules synthesis can be useful in understanding of plant response to the environmental stress. Salicylic acid is one of the signal molecules and endogenous regulators, which have an important role in regulation of some physiological processes including photosynthesis. In the present work, the effects of drought stress with salicylic acid on Hibiscus sabdariffa were investigated. These plants were exposed to three drought levels (0, 0.5, and 1 MPa) with different salicylic acid concentrations (0, 200, and 500 μM) in a factorial design. Results show that drought stress cause decrease in water relative content, pigments, and carbohydrate contents. However, salicylic acid can ameliorate water status and prevent decrease of pigments and carbohydrate contents. Therefore, it can be concluded that salicylic acid can enhance .drought stress tolerance through accumulate soluble sugars and enhanced photosynthetic performance

Keywords:

salicylic acid , drought stress , Hibiscus sabdariffa