Table 2. Changes in GSH homeostasis.

Treatment	GSH (nmol·g−1 FW)		GSSG (nmol·g−1 FW)		GSH/GSSG
	ZD958	ZJY1	ZD958	ZJY1	ZD958	ZJY1
Control	39.3 ± 2.6D	28.3 ± 2.4D	56.7 ± 3.3b	49.5 ± 3.4c	0.69	0.57
CH4	37.6 ± 2.5D	24.2 ± 2.1D	68.2 ± 4.2a	57.3 ± 3.8b	0.55	0.42
PEG	103.4 ± 5.9A	74.4 ± 3.8C	48.6 ± 3.3d	43.2 ± 3.1d	2.12	1.72
PEG + CH4	98.7 ± 4.3B	69.8 ± 3.7C	52.1 ± 3.9c	49.4 ± 3.1c	1.89	1.41

5-d-old maize seedlings of ZD958 and ZJY1 were pre-incubated in the solution containing 0.65 mM CH₄ for 1 d, and then transferred to half-strength Hoagland solutions with or without 20% PEG-6000 for 2 d. Afterwards, GSH and GSSG contents in the seedling roots were determined. Control seedlings were incubated in Hoagland solution alone. Data are presented as means ± SE (5 root parts per experiment performed three times). Within each set of experiments, bars with different letters denote significant differences according to multiple comparisons (P < 0.05).