Table I. Overview of studies used to examine ion uptake and toxicity.

For each study, the pH, total concentration of ions ([I]_t), and the calculated ψ₀^o are reported. The ψ₀^o was calculated for each medium with the standard GCS model.

Species and Source	Experiment No.	pH	[Al]t or [La]t	[CaCl2]t	[Mg]t or [Sr]t	[NaCl]t	ψ0o
			μm	mm	mm	mm	mV
Ca2+ influx into PM vesicles of wheat roots (Huang et al., 1994)	1	7.0	[AlCl3] 0–20	0.01–5.0	[MgCl2] 0–0.5 [SrCl2] 0–0.5		–87.6 to –18.9
Ca2+ influx into PM vesicles of wheat roots (Huang et al., 1996)	2	4.5	[LaCl3] 0–20	0.01–3.0			–34.7 to –5.49
Cu2+ uptake by wheat seedlings (this study)	3	5.1–6.0		0.25–3.8	[MgCl2] 0.26–4.0	1.0	–44.4 to –19.3
Zn2+ uptake by pea seedlings (Wu, 2007)	4	4.3–6.0		0.19–1.8			–57.1 to –14.9
Ca2+ uptake by wheat roots (Davenport et al., 1997)	5	6.5		0–3.1		5.0–150	–86.4 to –6.6
Na+ uptake by wheat roots (Davenport et al., 1997)	6	6.5		0.08–11		5.0–150	–61.4 to –6.6
Cd2+ uptake by pea seedlings (Wu, 2007)	7	4.0–6.0		0.04–1.6			–76.0 to –8.7
Ni2+ uptake by pea seedlings (Wu, 2007)	8	4.0–6.0		0.04–1.8			–76.0 to –8.2
Cu2+ uptake by pea seedlings (Wu, 2007)	9	4.0–6.0		0.04–1.9			–75.9 to –8.3
H2AsO4− uptake by wheat seedlings (this study)	10	4.4–6.0		0.24–4.1	[MgCl2] 0.26–3.7	0.91	–43.8 to –19.1
Cu2+ rhizotoxicity to wheat seedlings (this study)	11	5.1–6.0		0.25–3.8	[MgCl2] 0.26–4.0	1.0	–44.4 to –19.3
Cu2+ rhizotoxicity to wheat seedlings (Parker et al., 1998)	12	4.5–6.0		0.20–4.0	[MgCl2] 0–4.7		–56.6 to –12.7
Cu2+ rhizotoxicity to wheat seedlings (Kinraide, 2006)	13	4.5–5.7		0.50–8.0		0 - 10	–33.4 to –8.7
Al3+ rhizotoxicity to wheat seedlings (Tyler wheat, archived data)	14	4.3	[AlCl3] 0–20	0.40–4.0	[MgCl2] 0–3.6		–25.3 to 0.8
H2AsO4− rhizotoxicity by wheat seedlings (this study)	15	4.5–6.0		0.27–4.3	[MgCl2] 0.26–4.0	0.53–20	–44.1 to –19.1