Abstract:

【Objective】The objective of the paper is to study the roles of pathogen-originated hydrogen peroxide (H2O2) in the interaction between plant and pathogen.【Method】Localization of H2O2 accumulation was investigated in the non-host interaction between rice and Xanthomonas campestris pv. phaseoli (Xcp) by using histochemical analysis under electron microscopy. 【Result】The lack of Alkyl hydroperoxide reductase subunit C led to compensatory increase in the activities of H2O2 scavenging, and always resulted in significant decrease of endogenous H2O2 accumulation in ahpC mutant strain compared with the wild-type strain of Xcp, which has impact on the mean level of H2O2 accumulation in this interaction during the interaction with plant.【Conclusion】The results suggest that bacterial pathogen is a potential source for the H2O2 accumulation in the interaction between rice and Xcp. In addition, the H2O2 produced by bacteria may be an important cause for plant cell injury undergoing the HR during non-host resistance.

Key words: alkyl hydroperoxide reductase subunit C gene (ahpC), hydrogen peroxide, non-host interaction, Xanthomonas campestris pv. phaseoli