The antioxidant enzyme activities in cultivated and Tibetan wild barley genotypes.

<p>Barley plants were exposed to alone and combined stresses of drought and salinity on superoxide dismutase (SOD, A) , peroxidase (POD, B), catalase (CAT, C) and ascorbate peroxidase (APX, D) in flag leaves of three barley genotypes during anthesis stage at 4% soil moisture level. Error bars represent SD values (n=4). Different letters indicate significant differences (P<0.05) among the treatments within each genotype. Control, drought, salinity and D+S correspond to normal growth condition without drought and salinity stress, drought stress (D, seedlings were subjected to drought stress for 20 d during anthesis by withholding irrigation until the soil moisture content (SMC) reduced to 4%), salinity stress (S, 1 L 200 mM NaCl solution was added per pot at anthesis stage and then kept humid throughout the experimental period), combined stresses of drought and salinity (D+S, 1 L 200 mM NaCl solution was added per pot at anthesis stage, then subjected to drought stress until SMC reduced to 4%), respectively.