Molecular resistance mechanism of phytopathogenic oomycete to several important fungicides

Plant pathogenic oomycetes could cause many devastating diseases. Currently, chemical control is still one of the most effective methods for the control of oomycete diseases. However, many fungicides against oomycetes have generated serious resistance problems because of unreasonable and frequent applications in fields. The mode of action, resistant genetic mechanism and molecular resistance mechanism of several most commonly used fungicides were reviewed, such as phenylamides (PAs), carboxylic acid amides (CAAs), quinone outside inhibitors (QoIs), oxysterol binding protein inhibitors (OSBPIs) and tubulin inhibitors. The current knowledge summaried in this review will contribute to the scientific control of plant pathogenic oomycetes and provide a valuable reference for future research. Existing literature reports demosntaretd that point mutation in target protein could cause resistance to PAs, CAAs, QoIs, OSBPIs and tubulin inhibitors. PAs and tubulin inhibitors resistance were controlled by more than one gene, and QoIs resisitance was maternal inheritance. It was speculated that OSBPIs resistance was controlled by one dominant gene. However, there was distinct difference in genetic mechanism for different CAAs fungicides.