Effect of plant growth promoting rhizobacteria and foliar application of silicic acid and amino acids on destruction antioxidant enzyme activity of barley under drought stress

using of Bio fertilizers asplant growth promoting bacteria, silicic acidandamino acids for reducing of drought stress in plants and improving physiological parameters such as antioxidant enzymesand thus raising the level of plant yield in arid and semiarid areas are emergency management for drought control agriculture and also in barley agronomy.Thus, this study was carried out in 2009 in Agricultural Research station, Karaj Islamic Azad University with irrigation factor at two levels, Includes A1:full irrigation and A2:cut irrigation after flowering stage and second experimental treatments at The five levels, includes B1: control, B2: seed inoculated with bacteria, B3: seed inoculated with bacteria + sprayed silicic acid, B4: seed inoculated with bacteria + sprayed amino acids and B5: seed inoculated with bacteria + sprayed silicic acid and sprayed amino acids in randomized complete blocks design with four replicates using analysis of split plot. Analysis of variance showed that the irrigation effect on all traits in the1 percent level is significant. The highest seed yields were related to the normal irrigation. The highest levels of super oxide dismutase, glutathione peroxidase and catalase related to cut irrigation after flowering stage. The interactions showed that the highest seed yield related normal irrigation and seed inoculated with bacteria + sprayed silicic acid and sprayed amino acids, respectively. The highest levels of super oxide dismutase, glutathione peroxidase and catalase belonged to cut irrigation after flowering stage and seed inoculated with bacteria and sprayed silicic acid+ sprayed amino acids (472/8, 156/1 and 222/9 U/ g protein)respectively.