Overexpression of () Promotes Potato Tolerance to .

Reactive oxygen species (ROSs) represent one of the first lines of plants' biochemical defense against pathogens. Plants' respiratory burst oxidase homologs (RBOHs) produce ROSs as byproducts in several cellular compartments. In potato tubers, respiratory burst oxidase homolog (StRBOHs) are involved in suberization and healing of wounded tissues. StRbohA has been tested in the model plant , which led to enhanced plant defense against the soilborne pathogen . Here, we showed that overexpressing in potato plants increases plant tolerance to the oomycete , the causal agent of late blight disease. Transgenic potato plants expressing showed reduced disease symptoms (necrosis) compared with the wild type. In parallel, the expression of pathogenesis-related genes (); ; antioxidation-related genes , , , , and ; and genes involved in the biosynthesis pathways of jasmonic and salicylic acids (, , , , , and ) exhibited significant increases in transgenic plants in response to infection. After higher expression of , ROSs accumulated more in inoculation sites of the transgenic plants. ROSs act as signals that activate gene expression in the salicylic acid (SA) biosynthesis pathway, leading to the accumulation of SA and triggering SA-based defense mechanisms. SA-responsive showed higher expression in the transgenic plants, which resulted in the restriction of pathogen growth in plant tissues. These results demonstrate the effective role of StRbohA in increasing potato defense against .