Mechanical Forces and Signal Transduction in Growth and Bending of Plant Roots

Abstract

The tissues of the root elongation zone consist mainly of cell walls that form a solid deformable framework and of a multitude of intracellular volumes containing fluid under turgor pressure. The fluid exchange takes place in different ways: via the apoplasm that includes extracellular space and cell wall pores, and via plasmodes-mata providing direct communication between intracellular volumes. The cell-file structure of the tissue permits relatively distinct partitioning of longitudinally and transversely oriented walls. This geometrical organization allows one to postulate simple relations between macro- and microparameters for the tissue.