Fiziol. rast. genet. 2020, vol. 52, no. 1, 3-30, doi:

Cytokinins in cereals ontogenesis and adaptation

Vedenicheva N.P., Kosakivska I.V.

  • M.G. Kholodny Institute of Botany, National Academy of Sciences of Ukraine  2 Tereshchenkivska St., Kyiv, 01601, Ukraine

Cytokinins are one of the most important components of the phytohormonal complex. They are involved in the regulation of all vital functions of the organism, including cell division, formation of meristems, responses to the negative effects of the environment, photosynthesis and aging, absorption of macro- and microelements etc. The vast majority of the data were obtained as a result of studies using dicotyledonous plants, which differ in morphology and physiological characteristics from monocotyledonous plants. This makes the comparative analysis of regulatory systems in plants of these two classes relevant. The modern literature data concerning the characteristics of the cytokinin metabolism in cereals were analyzed, the specificity of the cytokinins role in controlling the processes of formation, dormancy and seed germination, the development of inflorescences and roots, organism aging, the formation of adaptive responses to abiotic and biotic stresses were considered, and the anti-stress effect of the hormones were described. Relationship between the productivity of cereal plants and the level of various forms of endogenous cytokinins or exogenous treatment with them was emphasized. The effect of gene modifications on the productivity of rice, wheat, barley, and maize is disscused as well as on their tolerance to different environment factors. Particular attention is paid to the involvement of highly specific protein promoters in the regulation of biosynthesis, metabolism, and cytokinin signaling genes. The information presented on cereals is compared with data obtained on dicotyledonous plants. The conclusion is drawn on the need to alter researches from model objects that are not of practical interest to an in-depth study of plants having good prospects for use.

Keywords: cytokinins, cereals, growth, development, adaptation, productivity

Fiziol. rast. genet.
2020, vol. 52, no. 1, 3-30

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