Table III.

5OP and thiol concentrations in BSO-treated oxp1-1 seedlings

BSO was added to liquid culture at 1 mm for the indicated days. All plants were 14 d old when harvested. Where indicated, BSO was added 1 to 4 d before the plants were harvested and the metabolites were measured. The 40% decrease in the 5OP concentration in the oxp1-1 mutant was caused by the 2.4-fold increase in plant biomass (1.19 ± 0.07 g per 30 plants at 10 d, 2.86 ± 0.10 g per 30 plants at 14 d; n = 6) during the of BSO treatment but not by 5OP metabolism in the oxp1-1 mutant. The means ± sd of five biological replicates are shown. N.D., Not detected.

Treatment	5OP	GSH	γ-EC	Cys
	nmol g−1 fresh weight
No BSO	5,280 ± 450	369 ± 55	12.2 ± 2.4	37 ± 5
1 d	4,990 ± 570	71 ± 26a	5.6 ± 1.9a	57 ± 4a
2 d	4,740 ± 240a	36 ± 5a	N.D.	52 ± 10a
3 d	3,970 ± 390a	27 ± 3a	N.D.	62 ± 9a
4 d	3,160 ± 280a	31 ± 4a	N.D.	64 ± 5a

^aSignificant difference from nontreated plants (one-tailed Student's t test, P < 0.05).