Effects of salicylic acid on the induction of physiological and biochemical changes in Brassica napus L. under water stress. Maryam Mazaheri Tirani1, 2*, Fatemeh Nasibi1 and Khosro Manoochehri Kalantari 1, 3

Drought stress is considered as a restricting factor in plant production and salicylic acid (SA) has been reported to minimize the harmful effects of many stresses including drought. In this study, salicylic acid was sprayed on the leaves of Brassica napus at the 4-leaf stage at concentrations of 0.5, 1 and 1.5 mM for two days. Plants were subjected to drought stress (withholding water for five days). Drought stress significantly reduced photosynthetic pigments (Chlorophyll and carotenoids) and anthocyanins content but increased lipid peroxidation, proline and ethylene. SA at 1 mM alleviated damage caused by drought stress on all parameters measured. It is concluded that salicylic acid can considerably alleviate damages caused by drought.