The expression of proline production/degradation genes under salinity and cadmium stresses in Triticum aestivum inoculated with Pseudomonas sp.

Soil pollution with heavy metals (such as Cd) and soil salinity are two important problems concerning the agricultural production with negative effect on crop quantity and quality in many parts of the world. Current research evaluated the expression of production/degradation genes in Triticum aestivum var. 'Chamran' inoculated with Pseudomonas sp. and exposed it to salinity (EC = 3, 10, and 16 dS m(-1)) and cadmium (Cd = 0, 25, and 50 mg kg(-1)). This study indicates that the exposure of wheat to salinity and Cd resulted in an increase in Cd2+ and an increase in Na+/K+ ratio of plant tissues as well as an increase in the expression of proline degradation gene. In lower tensions (EC10 and Cd25), an increase in expression of proline biosynthesis genes was observed. An increase in the proline content of plant tissues was also observed; however, in higher tensions (EC16Cd50) a decrease in these genes expression can be remarked. The inoculation of wheat seeds with Pseudomonas sp. diminished the effects of salinity and Cd stresses on plants and resulted in the increase in expression of proline biosynthesis genes, a decrease in expression of proline degradation gene, and a decrease in the Na+/K+ ratio and Cd2+ content in wheat tissues.