Exogenous Salicylic Acid Modulates the Response to Combined Salinity-Temperature Stress in Pepper Plants (Capsicum annuum L. var. Tamarin)

Abstract

Growers in the cultivated areas where the climate change threatens the agricultural productivity and livelihoods are aware that the current constraints for good quality water are being worsened by heatwaves. We studied the combination of salinity (60 mM NaCl) and heat shock stress (43 °C) in pepper plants (Capsicum annuum L. var. Tamarin) since this can affect physiological and biochemical processes distinctly when compared to separate effects. Moreover, the exogenous application of 0.5 mM salicylic acid (SA) was studied to determine its impacts and the SA-mediated processes that confer tolerance of the combined or stand-alone stresses. Plant growth, leaf Cl− and NO3− concentrations, carbohydrates, and polyamines were analyzed. Our results show that both salinity stress (SS) and heat stress (HS) reduced plant fresh weight, and SA only increased it for HS, with no effect for the combined stress (CS). While SA increased the concentration of Cl− for SS or CS, it had no effect on NO3−. The carbohydrates concentrations were, in general, increased by HS, and were decreased by CS, and for glucose and fructose, by SA. Additionally, when CS was imposed, SA significantly increased the spermine and spermidine concentrations. Thus, SA did not always alleviate the CS and the plant response to CS cannot be directly attributed to the full or partial sum of the individual responses to each stress.

Plants’ Physio-Biochemical and Phyto-Hormonal Responses to Alleviate the Adverse Effects of Drought Stress: A Comprehensive Review

“…Applying Salicylic acid (SA) to the leaves has induced plant stress tolerance. Several studies have found that Salicylic acid (SA) has beneficial effects on plants in terms of resistance to salinity, drought, and high temperatures [105,180,181]. The previous results suggested that Salicylic acid (SA) helps plants adapt to abiotic stresses [182].…”

Modulation of salt-induced stress impact in Gladiolus grandiflorus L. by exogenous application of salicylic acid

“…It might be ascribed to SA induced intensification Cl − ions in plants on account of increase in oxidative damage during high salt concentration. Accumulation of toxic anion (Cl −) in the leaves may possibly have compromised the photosynthetic machinery, which negatively alters growth 22 .…”

Molecular Regulatory Mechanism of Exogenous Hydrogen Sulfide in Alleviating Low-Temperature Stress in Pepper Seedlings

“…Capsicum is very sensitive to low temperatures, and low-temperature stress can seriously affect its growth and development, limiting its yield and quality [12]. Many exogenous substances, such as brassinolide (Br), salicylic acid (SA), and 5-aminolevulinic acid (ALA), can alleviate the stress caused by low temperatures in capsicum [22][23][24]. The effect of H 2 S on low-temperature stress in pepper mostly remains at the physiological level, and data on the signaling pathway in response to low-temperature stress remain limited.…”