Plant resistance to water deficiency is related to metabolic
changes and functional and structural rearrangements
of photosynthesizing tissues. These changes are
coordinated by regulatory systems, of which the most
important for processes of plant adaptation are those
involving cytokinins and other phytohormones. Cytokinins,
which regulate multiple functions in plant cells,
were shown to control the induction and stimulation of
synthesis of critical plant proteins and increase the stability
of the photosynthetic apparatus during water defi-
ciency and under other unfavorable conditions