Visualization of X. oryzae pv. oryzae expressing GFP in planta. TP309 (A and C) and TP309-XA21 (B and D) were inoculated with PXO99GFP, harvested at 12 DAI, and then visualized under Zeiss Axiophot fluorescence microscope (Jena, Germany). Transverse sections (A and B) and leaf surface (C and D) were observed with excitation from 450 to 490 nm and emitted light collected at 520 nm at × 40 (A and B) and × 10 (C and D) magnification. Bars in A and B, 50 μm. Bars in C and D, 10 μm.