Effect of salicylic acid on biochemical changes in wheat plants under khat leaves residue

Abstract

Residues of khat (Catha edulis Forskal) leaves in the soil showed an inhibitory effect on the dry mass, pectin and cellulose of wheat shoots and roots and cell wall-associated proteins of roots. The dry mass of shoots and roots significantly reduced and the reduction in roots was greater than in shoots. On the other hand, the contents of hemicellulose and lignin in both shoots and roots and cell wall-associated proteins of shoots were stimulated by the amount of khat leaves added to the soil. Soaking wheat caryopses in salicylic acid (SA) counteracted partially or completely the adverse effect of khat leaves residues on pectin and cellulose composition. The dry mass of wheat shoots and roots increased by SA to about 1.5-3 folds of SA-untreated plants. The content of hemicellulose and lignin of shoots and roots was antagonistically lowered by the application of SA. The application of SA was generally associated with a marked increase in the biosynthesis of cell wall-associated proteins of shoots and roots of wheat plants. Soluble proteins, proline and free amino acids increased significantly in plants growing in soil amended with khat leaves residues; however, SA inhibited this stimulatory effect. Soaking of wheat caryopses in SA had a favorable effect on the accumulation of nutritive cations; it also ameliorated the effect of more distressing ions, especially Na, accumulated in wheat plants due to mixing khat leaves residues with the soil.

Investigation on Allelopathic Effects of Khat Leaves Residues and Alleviative Effects of Salicylic Acid in Wheat Roots

“…Soaking of wheat caryopses in SA such arrangement was changed to be cellulose > pectin > hemicellulose. This is in a good agreement with our previous work on wheat plants [8].…”

“…On the other hand, salicylic acid (SA) acts as a potential non-enzymatic antioxidant, and is used also as an important signal for plant response modifying to environmental stressors. Some earlier reports display exogenous SA can ameliorate the damaging effects of khat leaves residues in wheat [8], drought stress in soybean [9] and salt stress in wheat [10]. The problem of khat in Yemen is that a Salicylic Acid in Wheat Roots considerable area of agricultural lands that must be cultivated with several economic crops is currently replaced by khat plantation.…”

“…The problem of khat in Yemen is that a Salicylic Acid in Wheat Roots considerable area of agricultural lands that must be cultivated with several economic crops is currently replaced by khat plantation. However, our previous study [8] was constrained to exhibit the inhibitory effects of khat leaves residues on the dry mass, cell wall and proteins of wheat plants. Since no detailed investigations on the effect of khat leaves on enzymatic and non-enzymatic antioxidants of plants have been revealed so far, we have devoted the present work to study the allelopathic effect of khat leaves on some biochemical characterization of wheat roots, and to investigate the role of SA in amelioration of these effects.…”

Salicylic Acid-Mediated Alleviation of Cadmium Toxicity in Maize Leaves

“…The pretreatment with SA also significantly increased the ascorbate content. This is well agreed with our results reported earlier [28].…”

Exogenous Application of Salicylic Acid and Nitric Oxide on the Ionic Contents and Enzymatic Activities in NaCl-Stressed Soybean Plants

“…Also, It is reported that NO enhanced salt tolerance in maize seedlings, through increasing K + accumulation in root, leaves and sheathes, while decreased Na + accumulation [25]. Furthermore, treatment with SA could decrease the Na + uptake, while increased the uptake of K + and Ca 2+ in Catha edulis [26]. Ca 2+ is widely accepted as an important second messenger in the intracellular signal transduction from the cell surface to internal compartments of the cell [27].…”