Fig. 5.

Effects of pretreatment with the MAPKK inhibitors PD98059 and U0126 on the expression of ZmrbohA–D in leaves of maize plants exposed to ABA treatment. The detached plants were pretreated with distilled water, U0126 (10 μM) and PD98059 (100 μM) for 6 h, respectively, and then exposed to ABA (100 μM) for 45 min and 105 min, respectively. The plants treated with distilled water under the same conditions during the whole period served as controls for the above. Relative expression levels of Zmrboh genes, analysed by real-time quantitative PCR, are presented as values relative to those of the controls, defined as 1, after normalization to Zmactin transcript levels. Values are means ±standard error (n=3). Means were compared by Duncan's multiple range test at 45 min and 105 min, respectively. Means denoted by the same letter did not significantly differ at P <0.05.