Evaluation Effect of Salicylic Acid and Glycine Betaine on Quantitative Properties of Alfalfa (Medicago sativa L.) under Drought Stress Conditions

Fertilizer management plays an important role for obtaining satisfactory yields and to increase crop productivity. One of limitation factor in agricultural plants production in dry areas in the water tension at growth step negative effect of water tension on corn growth depends on the time of tension occurrence, the intensity, plant growth and genotype step. This study was done to assess effect of amino acids on alfalfa crop production under water stress condition. Current research was conducted according split plot based on randomized complete blocks with three replications in Karaj Research Farm. The main factor included water stress (S1: full irrigation, S2: Cut off irrigation from the beginning of flowering until the end of the growing season, S3: Cut off irrigation from 50% of flowering until the end of the growing season) and Foliar application of amino acid (A1: without foliar spraying, A2: 0.5 mM salicylic acid, A3: 1 mM salicylic acid, A4: 10 mM glycine, A5: 50 mM glycine) belonged to sub plots. The difference between the mean of the traits in the treatments of using the reducing agent and not using these substances were considered significant. The results showed the adverse effect of drought stress on all studied traits and the reduction of its destructive effects by stress reducing agents. In determining the yield of wet and dry forage, the simultaneous use of full irrigation and glycine foliar application was the best treatment. According to the results, the use of 10 mM glycine betaine is recommended. In both stress treatments (cessation of irrigation from the beginning of flowering and cessation of irrigation from 50% of flowering) when stress relieving treatments were used, the effect of stress was significantly reduced as in most traits.