Fig. 5. Scanning electron microscope (SEM) observation of the upper epidermis ultra-structures of duckweed: (a) SEM image of duckweed frond from the control group in high magnification, bar = 50 μm; (b) SEM image of duckweed frond from the 1.0 × 10−4 mg L−1 abscisic acid (ABA) medium in high magnification, bar = 50 μm; (c) SEM image of duckweed frond from the 1.0 × 10−2 mg L−1 ABA medium in high magnification, bar = 50 μm.
