Table III.

Changes in turgor pressure (MPa) when agar blocks were applied to the surface of the accelerating region of the elongating zone of the root (3 to 4 mm from the apex at the start of the experiment)

Turgor was measured in either the epidermis or exodermis. Measurements were made at the sites at which the agar blocks had been applied, 6 and 20 mm (mature region) from the root apex. Data represent means ± sd (n = 4–8). The asterisk indicates significant difference at the 1% level between treatments (Student's t test).

Region	Water Potential of Agar Blocks	Time after Start of Treatment
		0.5	2	4
	Mpa		h
4 mm from the apex	−0.03	0.51 ± 0.05	0.44 ± 0.08	0.51 ± 0.04
	−1.60	0.29 ± 0.05*	0.47 ± 0.08	0.46 ± 0.09
6 mm from the apex	−0.03	0.50 ± 0.02	0.50 ± 0.04	0.48 ± 0.02
	−1.60	0.49 ± 0.02	0.52 ± 0.03	0.48 ± 0.02
Mature	−0.03	0.46 ± 0.06	0.41 ± 0.03	0.46 ± 0.03
	−1.60	0.39 ± 0.06	0.46 ± 0.05	0.43 ± 0.03