Potential of exogenously sourced kinetin in protecting Solanum lycopersicum from NaCl-induced oxidative stress through up-regulation of the antioxidant system, ascorbate-glutathione cycle and glyoxalase system

Abstract

The protective role of exogenously applied kinetin (10 μM KN, a cytokinin) against the adverse effects caused by NaCl-induced (150 mM) stress in Solanum lycopersicum was investigated. Application of KN significantly enhanced growth and biomass production of normally grown plants (non-stressed) and also mitigated the adverse effect of NaCl on stressed plants to a considerable extent. Among the examined parameters, chlorophyll and carotenoid contents, photosynthetic parameters, components of the antioxidant system (both enzymatic and non-enzymatic), osmotica accumulation, and mineral uptake exhibited a significant increase following the application of KN. Furthermore, KN application reduced the generation of reactive free radical hydrogen peroxide, coupled with a significant reduction in lipid peroxidation and an increase in membrane stability. The activities of antioxidant enzymes, and glyoxylase system were found to be promoted in plants exposed to NaCl, and the activities were further promoted by KN application, thereby protecting S. lycopersicum plants against NaCl-induced oxidative damage. Further strengthening of the antioxidant system in KN supplied plants was ascribed to regulation of ascorbate-glutathione cycle, phenols and flavonoids in them. The levels of proline and glycine betaine increased considerably in KN-treated plants, thereby maintaining relative water content. Moreover, exogenous KN application reduced the inhibitory effects of NaCl on K+ and Ca2+ uptake, which resulted in a considerable reduction in tissue Na+/K+ ratio.

Exogenous Nitric Oxide Mitigates Nickel-Induced Oxidative Damage in Eggplant by Upregulating Antioxidants, Osmolyte Metabolism, and Glyoxalase Systems

“…Increased antioxidant functioning due to NO application prevents the oxidative effects on the structure and function of chloroplast thylakoids [17]. In the present study, NO-mediated enhancement in the APX and GR activities and synthesis of AsA and GSH reflects in improved electron transport through maintenance of NADP [12]. Such effects of exogenous SNP were evident as increased photosynthetic rate.…”

“…Compared to Ni-stressed and control, SNP-treated exhibited declined accumulation of MG, thereby preventing the possible toxic effects of MG on cellular stability. Earlier upregulation of glyoxalase-I due to kinetin [12] and NO [9] application has been demonstrated to mitigate salinity and cadmium mediated growth decline. However, reports discussing the effect of SNP on glyoxalase under Ni stress are not available.…”

“…Another important mechanism i.e., glyoxalase system includes two key enzymes: glyoxalase I and II mediating the detoxification of methylglyoxal (MG) [9]. Exogenous supplementation of phytohormones strengthen the tolerance mechanisms and improve tolerance of crop plants to a variety of stresses [5,8,[12][13][14].…”

Beneficial role of acetylcholine in chlorophyll metabolism and photosynthetic gas exchange in Nicotiana benthamiana seedlings under salinity stress

“…; Ahanger et al . ). Studies have confirmed that Na + competes with K + for binding sites, thus reducing the uptake and accumulation of K + in plants (Hasegawa ).…”

Combined Kinetin and Spermidine Treatments Ameliorate Growth and Photosynthetic Inhibition in Vigna angularis by Up-Regulating Antioxidant and Nitrogen Metabolism under Cadmium Stress

“…The damaging effects of Cd at physiological and biochemical levels have been largely attributed to the excessive generation of ROS resulting in protein degradation, nucleic acid damage, photoinhibition, and membrane damage [5][6][7]. Indigenously occurring tolerance mechanisms that include the antioxidant system, the accumulation of compatible osmolytes, and secondary metabolites are employed to counteract the damaging effects of stresses [6,8].The antioxidant system is comprised of enzymatic and non-enzymatic components [9,10]. Efficient working of the antioxidant system, osmolyte, and secondary metabolite metabolism results in the quick elimination of ROS from different cellular components for better stress amelioration and growth maintenance [2,10].…”