Pathogenicity and virulence test for PXO99
in planta. A. Water-soaked disease lesions on two leaves from TP309 and TP309-XA21 at 12 days after PXO99 or PXO99GFP strains inoculation. B. After culture of PXO99 and PXO99GFP strains on PSA plates containing cephalexin, cells were diluted to 1.0 × 108 CFU/ml, and then inoculated onto rice leaves of TP309 (susceptible) and TP309-XA21 (resistant) lines using the scissor clipping method. Bacteria were recovered from the leaves at 0 (white bar) and 12 (grey bar) DAI and serially diluted, and then spread on PSA plates containing either cephalexin or cephalexin/kanamycin for colony counting. Each bar represents averages ± standard deviation of three sampled leaves per treatment. The experiments were repeated three times with more than ten rice leaves from three individuals each time. Km, kanamycin.