Fig. 2From: Integrative physiological, metabolomic, and transcriptomic analysis reveals the drought responses of two apple rootstock cultivarsEffect of drought stress on the superoxide anion (\({O}_{2}^{\stackrel{-}{\bullet }}\)) production rate (A), malondialdehyde (MDA) content (B), superoxide dismutase (SOD) activity (C), and proline (Pro) content (D) of ‘Jizhen-2’ and ‘ZC9-3’Back to article page