Effects of lead (Pb, 150 and 300 µM) alone or in combination with methyl jasmonate (MJ, 0.5 and 1 μM) on the contents of reduced ascorbic acid (AsA, A), oxidized ascorbic acid (DHA, B), reduced glutathione (GSH, C) and oxidized glutathione (GSSG, D) and the ratios of AsA/DHA (E) and GSH/GSSG (F) in rice leaves. Values (means ± SD, n = 5) followed by the same letter are not significantly different (P < 0.05; LSD test)