Figure 5. Exogenous ABA can reduce stomatal aperture and inhibit foliar bacterial growth under high RH.

A, Stomatal aperture in V. faba leaves dip-inoculated with mock or DH5α (10⁸ CFU/ml) supplemented with the indicated concentrations of ABA under ambient and high RH conditions. Results represent means of three replicates ±SEM, (n = 120 stomata). “+” and “−” represent presence or absence of DH5α cells in the inoculum. Asterisks denote significant differences as analyzed by two-tailed t-test (**, P<0.01; ns, no statistical difference); B, Bacterial population in V. faba leaves at day 3 after dip inoculation with DH5α. “+” and “−” represent presence or absence of ABA (20 µM) in the inoculum.