Table II.

Rapid effects of root addition of Hg ions on growth rate and L in water-stressed rice

Treatment	Growth Rate	L
	μm min−1	min−1 MPa−1 × 10−3
+PEG
− Hg	3.5  ± 0.2	2.3  ± 0.3
+ Hg	1.8  ± 0.1 (49)	1.3  ± 0.2 (43)

Seedlings of paddy rice (cv IR20) were stressed for 24 h by exposure to PEG 6000 (−0.2 MPa water potential) prior to also adding Hg (0.5 mm HgCl₂) to the aerated root medium. Growth rates and L were assayed using the osmotic-jump method after 20 min of Hg treatment (means ± se, n = 6). Numbers in parentheses are percentage reductions caused by Hg ions.