Bacterial Impact on H₂O₂ Accumulation during the Interaction between Xanthomonas and Rice

Abstract

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.