Effect of salt and PEG to antioxidant enzymes activity and MDA concentration of Luffa cylindrical Roem

The activity of anti-oxidant enzymes(Superoxide dismutase(SOD),Peroxidase(POD),Catalase(CAT)),parameters of oxidative stress malondialdehyde(MDA),soluble sugar(SS) and chlorophyll content of shoots were investigated in L.cylindrical.The seedlings of L.cylindrical were treated with varying NaCl(0,50,100,150 mmol/L) and PEG(0,10%,15%,20%) stress.The activities of SOD,POD and CAT showed different developing tendencies with the increase of the concentration of NaCl or PEG in shoots of L.cylindrical,but it was higher under stress conditions than control.MDA concentration of shoots increased than decreased under salt stress condition,but it was higher under stress conditions than control,MDA concentration of shoots decreased under PEG stress condition.SS concentration of shoots increased than decreased under salt stress condition,but it increased with PEG concentration increased obviously.Chlorophyll content of shoots decreased under stress conditions.The stress tolerance of L.cylindrical under salt and PEGr stress condition are probably due to its ability to exhibit high SOD,POD and CAT enzyme activities and osmotic adjust action of soluble sugar.