Towards understanding of tree growth regulation.

Many of the regulatory circuits underlying plant growth and development processes still remain to be discovered. However, it has become increasingly clear that basic signal perception and transduction mechanisms (involving cytoplasmic calcium ions) and their associated biochemical cascades play a key role in these phenomena. From this point of view, the regulation of tree growth and shape constitute one of the most challenging issues, not only because of its apparent complexity, but also because of its major impact on many agricultural or forestry problems.