Salicylic Acid Induction of Flavonoid Biosynthesis Pathways in Wheat Varies by Treatment

Abstract

Salicylic acid is a promising compound for the reduction of stress sensitivity in plants. Although several biochemical and physiological changes have been described in plants treated with salicylic acid, the mode of action of the various treatments has not yet been clarified. The present work reports a detailed comparative study on the effects of different modes of salicylic acid application at the physiological, metabolomic, and transcriptomic levels. Seed soaking and hydroponic treatments were found to induce various changes in the protective mechanisms of wheat plants. The possible involvement of the flavonoid metabolism in salicylic acid-related stress signaling was also demonstrated. Different salicylic acid treatments were shown to induce different physiological and biochemical processes, with varying responses in the leaves and roots. Hydroponic treatment enhanced the level of oxidative stress, the expression of genes involved in the flavonoid metabolism and the amount of non-enzymatic antioxidant compounds, namely ortho-hydroxycinnamic acid and the flavonol quercetin in the leaves, while it decreased the ortho-hydroxycinnamic acid and flavonol contents and enhanced ascorbate peroxidase activity in the roots. In contrast, seed soaking only elevated the gene expression level of phenylalanine ammonia lyase in the roots and caused a slight increase in the amount of flavonols. These results draw attention to the fact that the effects of exogenous salicylic acid application cannot be generalized in different experimental systems and that the flavonoid metabolism may be an important part of the action mechanisms induced by salicylic acid.

Salicylic acid‐enhanced biosynthesis of pharmacologically important lignans and neo lignans in cell suspension culture of Linum ussitatsimum L

“…These results indicate that SA showed positive impact on biosynthesis of TFC. Similarly, some researchers have reported positive impact of SA on flavonoid biosynthesis in various plant species which endorse our results . The accumulation of flavonoids in these studies were related to high expression of genes and enzymes involved in biosynthesis of flavonoids which might be in our case here as well.…”

Characterization, culture medium optimization and antioxidant activity of an endophytic vitexin-producing fungus Dichotomopilus funicola Y3 from pigeon pea [Cajanus cajan (L.) Millsp.]

“…As an important signal molecule, salicylic acid may stimulate the flavonoid biosynthesis pathway (Gondor et al . ). Metal ions belonged to the abiotic elicitors.…”

Pre‐véraison treatment of salicylic acid to enhance anthocyanin content of grape (Vitis vinifera L.) berries

“…Plants also produce anthocyanins as a protective mechanism in stress conditions. They accumulate in plant tissues under the influence of environmental stimuli …”

“…Salicylic acid, a natural phenolic compound and a signaling molecule with ubiquitous distribution in plants, is found in many plant tissues . This compound is considered as a plant hormone .…”

“…They accumulate in plant tissues under the influence of environmental stimuli. 12,13 Phenylalanine ammonia-lyase (PAL) (EC 4.3.1.24) is an essential enzyme in the phenolic biosynthesis pathway that catalyzes the conversion of L-phenylalanine to trans-cinnamic acid and ammonia. 14 Thus, PAL is the first and decisive step in the phenylpropanoid pathway and is therefore involved in the biosynthesis of phenolic compounds in the plants.…”