Physiological responses of tobacco plants (Nicotiana rustica) pretreated with ethanolamine to salt stress

Plant exposure to stress results in the decomposition of their cell membrane phospholipids, and therefore it can elevate the level of EA (ethanolamine) in the cell, and this elevated level of EA induces an alarm response that activates cellular resistance and tolerance mechanisms. In the present study, in vitro cultured tobacco plants (Nicotiana rustica L.) were pretreated with ethanolamine (EA) before salt treatment. After 3 weeks of salt treatment (200 mM NaCl), the plants pretreated with exogenous EA showed the elevated levels of SOD, CAT and APX activity compared with unpretreated plants. Furthermore, total antioxidant capacity, fresh and dry weight and the content of photosynthetic pigments were also increased. In contrast, H₂O₂content decreased under similar conditions. According to the results of this study, it can be suggested that EA pretreatment increased salt tolerance of tobacco plants at least partly by stimulation of antioxidative responses.