The primary objective of this study was to investigate the beneficial effects of seed priming and foliar spray of potassium silicate on antioxidant activities under different salinity levels, thereby potentially improving wheat growth. Seeds were soaked into solutions containing potassium silicate (K 2 SiO 3 , 1.5 mM) for 6 h, while foliar spray with K 2 SiO 3 (4 mM) was applied at the early and the late stages of tillering. Lake Urmia water was used to prepare salinity levels of 0, 3, 5, 8, 10, 12, and 14 dS m 21 . For such traits as anthocyanin, catalase, ascorbate peroxidase, guaiacol peroxidase, and superoxide dismutase activity, an initial increase was observed at lower salinity levels; higher salinities subsequently decreased these traits or they remained mostly constant. Salinity also increased phenol, malondialdehyde, hydrogen peroxide, and polyphenol oxidase, but decreased flavonoid, nitrate content, and nitrate reductase activity. Seed priming and foliar spray provided effective approaches to reduce reactive oxygen species (ROS) manifestation in wheat grown under saline conditions. The improved antioxidant defense abilities by seed priming and foliar spray alleviated the oxidative damage of proteins and lipids and improved nitrate content and nitrate reductase activity.
Context Salinity is a major cause of yield loss in wheat globally. Aims and Methods To investigate the potential of silicon to minimise the effect of salinity in wheat, experiments were conducted using outdoor pots subjected to seven salinity treatments. Silicon (as potassium silicate K2SiO3) was applied as both a priming agent and foliar spray. Selected response functions were used to quantify wheat response to salinity as affected by silicon application. Key results Concentration of chlorophyll a, chlorophyll b and carotenoid decreased by 4.2, 3.6 and 1.4 mg/g FW respectively with increasing salinity up to an electrical conductivity of 14 dS/m. Increasing salinity levels increased maximum variable chlorophyll fluorescence yield in a dark-adapted state and decreased the photochemical quenching coefficient, the nonphotochemical quenching coefficient, non-photochemical quenching, actual quantum yield of PSII electron transport in the light-adapted state, and the apparent photosynthetic electron transport rate. The maximal efficiency of PSII photochemistry in the dark-adapted state was not significantly influenced by salinity. The response functions showed that the salinity threshold value and the salinity at which a given trait was reduced by 50% (EC50) were 5.7 and 12.1 dS/m, respectively. Conclusions The combined treatment of silicon (priming × foliar spray) was found to be the most effective, increasing salinity threshold value and EC50 by 32 and 2% respectively. Implications These findings give insight into the effects of salinity on wheat and demonstrate the potential of silicon applications to promote crop health in saline environments.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.