Abstract

Wheat (Triticum vulgaris) plants were grown without NaCl and under salinization levels of NaCl. Salinity decreased the fresh, dry matter, water content, length and leaf area. Phytohormonal treatments with gibberellic acid (GA₃) or indole-3-acetic acid (IAA) caused a marked increase in these parameters; GA₃ was more effective than IAA. This activation was concomitant with the increase of osmotically active solutes, soluble sugars, soluble protein and amino acids. The accumulation of calcium and magnesium in root of plant treated with GA₃ and in shoot of plant treated with IAA may contributed in osmotic defense systems of wheat plants. The data also reveals that ethylene production was increased in salinity treatments. Spraying wheat plants with GA₃ increased the ethylene evolution while spraying with IAA decreased this evolution under salt stress conditions. Finally, it can be concluded that the GA₃ or IAA regulate the disturbances of metabolities and neglicated the negative effects of the accumlation of ethylene especially in plants treated with IAA under stress conditions which in turn resulted in a pronounced alleviated the drastic effects of salt.

Key words: GA_3, IAA, ethylene, salinity, wheat.