Plant Growth Regulators - Cytokinins
Cytokinins are substances close to purine bases (substituted adenins). It is a family of phytohormones essential for the development of the plant as well as auxin, which acts as hormones in plants.
Manufactured at the level of the root apex, they induce bud differentiation, subject to the presence of low doses of auxin. For higher concentrations, auxin inhibits bud differentiation. In high doses, auxin also inhibits bud break.
They are grouped into the same family because of the similarity of their effects. They all consist of an adenine, the difference being made on the side chain (in position 6).
They have activating properties of cell division, but they are also involved in cell growth and differentiation, among other things.
- Activation of chlorophyll production
- Enabling sheet opening
- Promote cell growth
- Promote the formation of young shoots
- Promote the unloading of sweet compounds by the phloem
- Delay foliar senescence
- Conjugated to auxin, they activate cell division (auxin promotes DNA duplication; cytokinins allow chromosome separation)
- Involved in morphogenesis
- Inhibit photosynthesis of C4 plants
- Stimulate the metabolism of young shoot cells (which are not at their maximum metabolism level) in response to an increase in water and available minerals.