Figure 1 Growth of GSB pathogenic fungi and accumulation of H2O2 and O2- in leaves of PI511890 and Payzawat. A : Growth of GSB pathogens on the leaves of Payzawat and PI511890 (40 ×). Co, Gt, Ap, Hy, Ih, and S represent conidium, germ tube, appresorium, hyphae, infection hyphae, and stoma, respectively. B : Leaves of Payzawat and PI511890 stained by diaminobenzidine at different time points afterS. cucurbitacearum inoculation. Payzawat-control and PI511890-control are the control groups sprayed with ddH2O. Payzawat-treatment and PI511890-treatment are the treatment groups sprayed with the GSB suspension of 5 × 105 spores/mL. C : Leaves of Payzawat and PI511890 stained by nitroblue tetrazolium at different time points afterS. cucurbitacearum inoculation. D : Boxplots for H2O2 accumulation quantified by Image J at different time points after S. cucurbitacearum inoculation.E : Boxplots for O2- accumulation quantified by Image J at different time points after S. cucurbitacearuminoculation. Least significant difference method was used for multiple comparisons of the means after ANOVA analysis. Ns represents no significance (p > 0.05). * represents p < 0.05. ** represents p < 0.01. *** represents p < 0.001.