An Efficient Rice Virus-Induced Gene Silencing System Mediated by Wheat Dwarf Virus

The virus-induced gene silencing (VIGS) technique can effectively inhibit systemic viral infection by down-regulating plant endogenous gene expression, and it has become an important tool to study plant gene function. However, few studies have reported that wheat dwarf virus (WDV), which enables high-throughput gene silencing, could be used in a rice VIGS system. In this study, a VIGS vector system was constructed based on WDV, and successfully silenced the Phytoene desaturase gene and the rice blast resistance gene Pi21 in rice. Pi21-silenced plants showed significantly increased resistance to rice blast, significantly reduced lesion area, and did not show high disease symptoms (grade 8–9). In addition, the WDV vector has the advantages of rapid infection, high proliferation, and an unconformity genome, and has little influence on rice growth and development. This study validates the effectiveness of the WDV-VIGS system in rice gene function studies and provides a new gene silencing tool for blast resistance breeding.