Abstract

Peroxidase (Prx)-related genes are reported to be involved in the metabolism of hydrogen peroxide (H2O2) in plants. Here, we found that the expression of thePdePrx12gene was upregulated in wild-type (WT) poplar line NL895 infected with the pathogensBotryosphaeria dothideastrain 3C andAlternaria alternatastrain 3E. ThePdePrx12gene was cloned in the poplar line NL895 and its overexpression (OE) and reduced-expression (RE) vectors were constructed. OE and RE transgenic lines were then generated. The H2O2content in the leaves was measured by DAB staining and spectrophotometric analysis, and the data revealed that the OE line had a reduced H2O2content, whereas the RE line had an increased H2O2content. These transgenic and WT plants were also inoculated with the 3C/3E pathogens. The leaf area infected by pathogen 3C/3E was determined and the OE line was found to have a larger area of infection, whereas the RE line was found to have a smaller area of infection. This result suggestedPdePRX12is involved in disease resistance in poplar. Given these results, this study demonstrated that when poplar is infected by pathogens, the expression ofPdePrx12is inhibited, leading to an increase in H2O2content, thereby enhancing disease resistance.Keywords:PdePrx12gene;Class III peroxidase;disease resistance;NL895 poplar