Effect of salt stress on some defense mechanisms of transgenic and wild potato clones (Solanum tuberosum L.) grown in vitro

Genetically modified plants (GMPs) proved to be a promising solution for many of biotic and abiotic stresses which affect food production. Great attention was given to the evaluation of growth, nutritional quality and safety of GMPs before release and commercialization. In this study, we targeted physiological and biochemical evaluation of transgenic potato plantlets under salt stress conditions. In vitro evaluation of salinity effects on transformed and non-transformed clones was investigated with four NaCI (0, 30, 60 and 90 mM). On exposure to NaCl for one month, the shoots height, fresh and dry weight of transformed clone showed significant decrease than those of non-transformed clone. Different biochemical parameters such as proline accumulation, lipid peroxidation, pigments content, ascorbate, and glutathione contents were tested in order to put forward the relative tolerance of both clones to salinity. Constitutive levels of these parameters were almost not similar between both clones. Additionally, electrophoretic analysis of total soluble protein (SDS-PAGE) and some isoenzymes such as acid phosphatase and esterase have revealed that plant subjected to NaCl showed induction in the synthesis of new polypeptides and isoformes. Our finding suggest that, the response of potato plantlets to salt stress may be accomplished by increasing the capacity of antioxidative system and the synthesis of new protein and isoenzymes which could be in turn contribute to select a salt resistant in potato. [Amal A. Mohamed, Mohamed A. Matter and Mahmoud M. Saker. Effect of salt stress on some defense mechanisms of transgenic and wild potato clones (Solanum tuberosum L.) grown in vitro. Nature and Science 2010; 8(12):181-193]. (ISSN: 1545-0740). http://www.sciencepub.net.