Figure 1

Displacement velocity as a function of distance from the root cap junction of primary roots of maize (cv FR697) growing in vermiculite under well-watered (WW; Ψ _w of -0.03 MPa) or water-stressed (WS; Ψ _w of -1.6 MPa) conditions. The spatial distribution of longitudinal expansion rate is obtained from the derivative of displacement velocity with respect to position. Regions 1 to 4, as described in the text, are indicated. Reproduced from Sharp et al. (2004) with permission from Oxford University Press.