Hamid Reza Miri1 and Mohammad Armin
In order to study the effect of glycine betaine on corn under drought condition an experiment was conducted as split-split plot in the base of randomized complete blocks design. The first factor were irrigation interval cycle (4 and 8 days) and second factor including different concentrations of glycine betaine (50 ppm, 100 ppm,150 ppm) and third was spraying in two times (stem elongation stage and before flowering). Analysis of variance showed that effects of three factors on all of parameters except for carotenoids were significant. However, foliar application of glycine betaine reduced effect of stress conditions on the plant so that extent of chlorophyll (a and b), plant height, yield and 1000 seed weight increased significantly. Spraying by glycine betaine caused improving plant performance in stress conditions, so that in the concentration of 150 ppm produced the highest quality in all of characterizations that preference was more evident before flowering. By considering these results it could be said that spraying with 150 ppm of glycine betaine before flowering in the condition of stress and without drought stress could improve the extent of chlorophyll (a and b), plant height, yield and yield components. Eventually it could be concluded that external glycine betaine with 150 ppm concentration while spraying before flowering had great positive effects and usage of that material is affected by time of application concentration and more stress severity