Fiziol. rast. genet. 2022, vol. 54, no. 3, 251-269, doi:

The role of amino acids in the regulation of stress resistance of the cereal crops

Romanenko K.O., Babenko L.M., Kosakivska I.V.

  • M.G. Kholodny Institute of Botany, National Academy of Sciences of Ukraine

Free amino acids are the precursors and components of proteins that are active participants in metabolic and physiological processes at different stages of cereal ontogenesis. Under the action of abiotic and biotic stressors, their content increases significantly, which allows us to consider amino acids as biomarkers of the stress state. The research results indicate a correlation between the ability to accumulate endogenous amino acids and stress resistance of plants. Hypersynthesis of amino acids contributes to the maintenance of cell turgor, osmotic balance, and stabilization of membranes. Such protective effects prevent the leakage of electrolytes from the cells; reduce the content of reactive oxygen species, prevent oxidative explosion. The review discusses the multiplex role of amino acids in plants exposed to abiotic stresses, with particular attention to the activation of antioxidant defense systems. Metabolic regulation involving amino acids is considered as the main strategy for the protection and survival of plants under unfavorable living conditions. The review provides examples of the successful use of exogenous amino acids and their derivatives to improve the stress resistance and productivity of cultivated cereals and the use of amino acid preparations in crop production.

Keywords: amino acids, proline, glycine betaine, abiotic stresses, resistance, cereals

Fiziol. rast. genet.
2022, vol. 54, no. 3, 251-269

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