Changes in growth, pigment content and antioxidants in the root and leaf tissues of wheat plants under the influence of exogenous salicylic acid

Abstract

The effect of various concentrations of salicylic acid (SA) on the growth, pigment content and the activity of antioxidants was investigated in the laboratory grown wheat plants. The root and shoot growth was affected at higher concentration of SA in early days of growth. The activities of catalase (CAT), ascorbate peroxidase (APX) and guaicol-specific peroxidase (POX) declined with the application of SA (50, 500 and 1000 µM), the decrease being more pronounced with the increase in SA concentrations both in the root and leaf tissues. On the other hand superoxide dismutase (SOD) activity increased with the application of SA. At low concentrations, SA has no effect on the activities of these enzymes in vitro. Salicylic acid at higher concentrations (5-and 10 mM) though inhibited CAT activity, the activities of APX and POX remain unchanged. High concentration of SA increased the level of H 2 O 2 and malondialdehyde both in root and leaf tissues. Thus, SA though has been reported to be a signal molecule for inducing various physiological and morphological attributes in plants, this study indicated the negative effect of the compound on growth and the activity of major enzymatic antioxidants.

Alleviation of Osmotic Stress Effects by Exogenous Application of Salicylic or Abscisic Acid on Wheat Seedlings

“…Supplementing SA or ABA to the medium (PEG + SA or PEG + ABA) caused a decrease of these seedling parameters for both cultivars. Similar observations were presented in a study by Sahu and Sabat [15], where SA was added to the culture of wheat seedlings in the early stage of growth under salinity stress conditions. ABA application significantly decreased dry shoot biomass and significantly increased leaf mass per area, root/shoot ratio, and fine root/total root ratio in Picea asperata [39].…”

“…PEG + ABA treatment caused a further increase of this parameter for susceptible SQ1 while it remained on the same level for resistant CS. Similarly, in investigations by Sahu and Sabat [15], it was noticed that exogenously applied SA increased MDA content in wheat plants, though only when applied in higher concentration. They concluded that SA in low concentration can regulate the activities of intracellular antioxidant enzymes and increase plant tolerance to environmental stresses.…”

“…[14], high ABA levels were maintained in SA treated wheat seedlings, which induced anti-stress reactions, such as the maintenance of proline accumulation. Sahu and Sabat [15] reported a negative effect of SA on growth and activity of major enzymatic antioxidants.…”

“…They have been proposed as a new category of plant growth regulators that can be involved in a large spectrum of physiological processes, and in addition, they have been shown to be an integral part of plant stress response [6,15,32]. Liu et al .…”

Effect of erythromycin exposure on the growth, antioxidant system and photosynthesis of Microcystis flos-aquae

“…Erythromycin can affect the membrane system; changes in MDA content can be used to gauge this effect. MDA is a peroxidation product of fatty acids of membrane lipids and is commonly considered as an important index of lipid peroxidation to reflect cellular oxidative damage under environmental stress [46,47]. In this study, the MDA contents were significantly higher in high erythromycin concentration treatments compared to the control, indicating that high erythromycin concentrations induced stronger peroxidation and caused more serious damage to the cell membrane.…”