Effects of salicylic acid on photosynthetic activity and chloroplast morphology under light and prolonged darkness

Abstract

Salicylic acid (SA) is a key component of plant defence, which exerts a concentration-dependent effect on photosynthesis under multi-faceted influence of light. Photosynthetic activities and chloroplast morphology were studied in tomato plants after treatment with a sublethal, 0.1 mM, and a cell death-inducing, 1 mM concentrations of SA under normal photoperiod during light phase and after a prolonged dark phase. SA (1 mM) decreased the maximal (Fv/Fm) and effective quantum yields of PSII [Y(II)] and PSI [Y(I)] under both environmental conditions, however, the photoprotective processes were not significantly different between light and dark samples. Decrease in grana height, thylakoid dilation and deformation of lumen were also observed in the light. In contrast to illuminated samples, 0.1 mM SA decreased Y(II) and Y(I) after dark incubation, but nonphotochemical energy dissipation and cyclic electron flow increased, suggesting that the photoprotective mechanisms could be activated in plants exposed to prolonged darkness. fluorescence yield in dark-adapted state; FM -fresh mass; Fv/Fm -maximum quantum yield of PSII; HR -hypersensitive response; LEF -linear electron flow; PN -net photosynthetic rate; qL -estimates the fraction of open PSII centres; qP -photochemical quenching; RC -reaction centres; ROSreactive oxygen species; SA -salicylic acid; TEM -transmission electron micrograph; Y(I) -effective quantum yield of PSI; Y(II)effective quantum yield of PSII; Y(CEF) -yield of cyclic electron flow around PSI; Y(NA) -the quantum yield of nonphotochemical energy dissipation in PSI due to acceptor side limitation; Y(ND) -quantum yield of nonphotochemical energy dissipation in PSI due to donor side limitation; Y(NO) -quantum yield of nonregulated nonphotochemical energy dissipation; Y(NPQ) -quantum yield of regulated nonphotochemical energy dissipation.

Time-Dependent Effects of Bentazon Application on the Key Antioxidant Enzymes of Soybean and Common Ragweed

“…Excess energy in PSII under light condition can lead to the production of ROS, which can destroy the electron transport components and PSII structure, causing more ROS production and initiation of cell death [60,61]. In accordance, photoinhibition in common ragweed plants and the significant decrease in NPQ after all bentazon treatments cannot dissipate excessive pressure accumulated in PSII reaction centres and cannot protect PSII under light conditions, which could result in high ROS production in chloroplasts of herbicide-treated leaves [62].…”

Timing of salicylic acid application affects the response of maize (Zea mays L.) hybrids to salinity stress

“…Application of SA to the rooting medium increased A, E, g s , C i and yield of two maize genotypes under salt stress in a dose-dependent manner, with marked genotypic variability (Tufail et al., 2013; Vazirimehr et al., 2014). In general, the influence of SA on tomato seedlings has been demonstrated to be dose-dependent; with moderate levels (0.1 mM) can be beneficial to photosynthetic efficiency but high levels (1 mM) may be toxic (Poór et al., 2019).…”

“…To alleviate the impact of abiotic stress on plant performance, several plant growth promoters as well as beneficial amendments such as SA and glycinebetaine have been examined in different modes of application, ranging from seed presoaking to foliar spray at different stages of plant development (Chen and Murata, 2008; Banu et al., 2010). It is likely that the effect of exogenous SA depends on several factors, including the dose, plant species, developmental stage and the mode of application (Horváth et al., 2015; Poór et al., 2019). The present work was conducted to resolve the role of timing of SA application to maize in alleviation of salt stress during the vegetative stage.…”

The Multifaceted Roles of Plant Hormone Salicylic Acid in Endoplasmic Reticulum Stress and Unfolded Protein Response

“…ROS generation by ER luminal oxidoreductase 1 (ERO1), the mitochondria-, and/or plastid-originated ROS [54] and NADPH-oxidase activity-dependent ROS [55] suggest a potential link between ER and other organelles in the oxidative processes. In this relation, SA could be an important signaling compound because SA has a significant effect on ROS production in a time- and concentration-dependent manner in these cell compartments [56,57,58]. However, the direct effects of SA on ERO1 and the relationship between ER and other organelles, which generate ROS, is not known.…”