Foliar application of sodium nitroprusside and salicylic acid alleviates the adverse effects of alkaline soil on roses

The purpose of this study was to investigate the effects of exogenous sodium nitroprusside (SNP), salicylic acid (SA) and their combination on some growth characteristics and physiological parameters in Rosa hybrida 'Beverly Watson' under alkalinity conditions. This experiment was conducted as a factorial experiment based on the completely randomized design with two factors in three replications and two pots in each replication. The factors were 4 concentrations of SNP (0, 0.5, 1 and 2 mM) and 5 concentrations of SA (0, 0.25, 0.5, 1 and 2 mM) as foliar application. In order to create alkaline soil, sodium bicarbonate was applied to the soil of pots until to be obtained pH=8. The results showed that 2 mM SA caused increasing in the activity of antioxidant enzymes, and 0.5, 1, and 2 mM SNP has positive effects on these factors. In this study, both SNP and SA increased growth characteristics such as fresh and dry weight of flowers and longevity of flowers on the shrubs and decreased alkaline stress, which may be a result of their role in a significant increase in activation of catalase (CAT), guaiacol peroxidase (GPX) and ascorbate peroxidase (APX). The application of SNP has a positive effect on proline content, but SA does not have any effect on it. As well, it was observed that they had synergistic effects in CAT activity, electrolyte leakage, and MDA content. Thus, the combination of SNP and SA can be a new indicator of a protective mechanism to lower lipid peroxidation, electrolyte leakage, and facilitate membrane transport to detoxify reactive oxygen species (ROS).

Automated summary

The study investigated the effects of exogenous sodium nitroprusside (SNP) and salicylic acid (SA) on growth characteristics and physiological parameters in Rosa hybrida 'Beverly Watson' under alkalinity conditions. Results showed that 2 mM SA increased antioxidant enzyme activity, while 0.5, 1, and 2 mM SNP had positive effects. Both SNP and SA increased growth characteristics and decreased alkaline stress by activating certain enzymes. Additionally, their combination showed synergistic effects in certain parameters, indicating a potential new protective mechanism against oxidative stress.