Oxidative markers in five Iranian alfalfa (Medicago sativa L.) cultivars under salinity stress . Nader Chaparzadeh1* and Faramarz Mehrnejad2

Five alfalfa (Medicago sativa L) cultivars from different areas of Iran were evaluated for oxidative markers under salinity conditions. Plants were grown in hydroponic condition by Hoagland nutrient solution containing different amounts of NaCl (control, 50 and 100 mM). Relative growth rate, membrane stability, lipid peroxidation, proline, hydrogen peroxide and relative water contents were determined. Results indicated that salinity decreased membrane stability, relative water content and growth parameters and increased lipid peroxidation, proline and hydrogen peroxide contents. Important variation was observed for all traits by increasing salinity. There were significant differences between cultivars in amounts of decrease or increase in the measured traits. In general, low membrane stability was observed in Sahand ava cultivar. Regarding salt stress, Yazdi cultivar was successful in maintaining membrane stability and relative growth rate.  Keywords:  Abbreviations:  AOS: activated oxygen species; MSI: membrane stability index; RGR: relative growth rate; RWC: relative water content; TBARS: thiobarbituric acid reactive substances    Chaparzadeh, N., F. Mehrnejad, 2013. 'Oxidative markers in five Iranian alfalfa (Medicago sativa L.) cultivars under salinity stress'. Iranian Journal of Plant Physiology 3 (4),793-799