Bacterial impact on H2O2 accumulation during the interaction between Xanthomonas and rice [Oryza sativa]

Localization of hydrogen peroxide (H2O2) accumulation during the interaction between rice and Xanthomonas oryzae pv. oryzae (X. oryzae pv. oryzae) was observed by histochemical analysis and electron microscopy. The changes that occurred in an avrXa7 mutant strain of X. oryzae pv. oryzae including the decreased production of endogenous H2O2, impacted on the mean level of H2O2 accumulation during the interaction with the plant. The results of catalase and aminotriazole treatments indicated that the changes of H2O2 accumulation during the interaction are induced by the impairment of endogenous H2O2 accumulation in X. oryzae pv. oryzae. These results suggested that bacterial pathogen is a potential source of the H2O2 accumulated in the interaction between rice and X. oryzae pv. oryzae.