Fig. 7.

Local longitudinal velocities throughout the distal zone of lupin roots, relative to the root apex. Roots were either unpressurized (0 kPa) or pressurized to 15 kPa for 47 h. Terminal velocities observed at points further than 10 mm from the root apex are thus equivalent to the elongation rate of the root axis. Observations are means ± s.e. The non-linear regression of logistic curves fitted was highly significant (P < 0·001); the two fitted logistic curves (for 0 kPa and 15 kPa roots, respectively) were significantly different (P < 0·001) and explained 98 % of the variance.