摘要：Nitric oxide (NO) is a key signaling molecule having various physiological functions in plants. Additionally, hydrogen peroxide acts as signaling molecules in plants. The second messenger, cGMP is a significant molecule for many different processes in plants. In the present study, the effects of drought stress and also sodium nitroprusside (SNP) and hydrogen peroxide (H2O2), externally applied at different concentrations, on nitric oxide (NO) levels, nitric oxide synthase (NOS) activity, cyclic GMP (cGMP) levels and hydrogen peroxide (H2O2) content in root tissues of the tolerant (Triticumae stivum L. Dogu-88) and sensitive (Triticum aestivum L. Yildirim) wheat plants were investigated. According to the results, NO level and NOS activity increased in both species. cGMP and NO levels increased. H2O2 content decreased in Dogu-88 plant but increased in Yildirim plant. All data revealed that the results were different in both wheat varieties. The results of the study, including the response of plant root tissues against stress and signal transduction, were found to be different. High NO levels can promote the adaptation to stress.
