Fiziol. rast. genet. 2024, vol. 56, no. 2, 130-150, doi:

Рhytohormones in growth regulation and the formation of stress resistance in cultivated cereals

Kosakivska I.V., Shcherbatiuk M.M., Vasyuk V.A., Voytenko L.V.

  • M.G. Kholodny Institute of Botany of National Academy of Sciences of Ukraine 2 Tereshchenkivska St., Кyiv, 01004, Ukraine

The study of abiotic stresses’ impact on the growth, development and productivity of cultivated cereals stands as one of the principal tasks of modern biological science. In response to stressors, plants modify their developmental pathway through morphological, physiological and biochemical reactions, thereby alleviating stress loads, limiting damage, and facilitating recovery processes. Phytohormones play a pivotal role in regulating all stages of the plant life cycle — from seed germination to senescence — under both optimal and stressful conditions. They serve as signaling triggers, initiating cascade of reactions that aid plants in adapting to adverse influences. Therefore, determining their content and localization sites is important for finding ways to control growth rate, development, and stress resistance formation. Among phytohormones, abscisic acid (ABA) is extensively studied for its involvement in responses to abiotic stresses. Stress-induced ABA accumulation, as a mechanism for slowing down metabolism, enables plants to adapt to adverse factors. Cytokinins and auxins also contributed significantly to the formation of adaptive plant responses, with stress-induced changes in their content and distribution being observed in numerous plant species. Gibberellins are closely associated with crucial developmental processes, making them essential for the precise implementation of plant genetic programs. The mechanism of stress resistance formation involving salicylic acid remains complex and not entirely understood. This hormone enhances osmolyte production, antioxidant activity, and interacts with other hormones. A promising strategy to increase the stability and yield of cultivated cereals involves the exogenous application of phytohormonal treatments, which effectively mitigate negative effects. Pre-sowing priming provides optimal conditions for initiating the metabolic processes during germination, minimizing seed quality and structure problems, and ensuring uniform, strong seedlings. Priming triggers metabolic processes that enhance growth and prompts alteration in the balance and distribution of endogenous hormones within plant organs. However, the mechanisms through which priming with exogenous phytohormones enhances seed germination, subsequent plant growth, and development remained insufficiently explored and not entirely understood. This review delves into recent advancements concerning the roles of both endogenous and exogenous phytohormones in regulating growth and fostering resistance to abiotic stresses in cultivated cereals.

Keywords: cultured cereals, phytohormones, growth, stress resistance, signaling systems

Fiziol. rast. genet.
2024, vol. 56, no. 2, 130-150

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