Establishment and application of a root wounding-immersion method for efficient virus-induced gene silencing in plants

In the post-genomic era, virus-induced gene silencing (VIGS) has played an important role in research on reverse genetics in plants. Commonly used -mediated VIGS inoculation methods include stem scratching, leaf infiltration, use of agrodrench, and air-brush spraying. In this study, we developed a root wounding-immersion method in which 1/3 of the plant root (length) was cut and immersed in a tobacco rattle virus (TRV)1:TRV2 mixed solution for 30 min. We optimized the procedure in and successfully silenced , tomato ( ), pepper ( L.), eggplant ( ), and phytoene desaturase ( ), and we observed the movement of green fluorescent protein (GFP) from the roots to the stem and leaves. The silencing rate of in and tomato was 95-100%. In addition, we successfully silenced two disease-resistance genes, and , to decrease disease resistance in tomatoes (CLN2037E). The root wounding-immersion method can be used to inoculate large batches of plants in a short time and with high efficiency, and fresh bacterial infusions can be reused several times. The most important aspect of the root wounding-immersion method is its application to plant species susceptible to root inoculation, as well as its ability to inoculate seedlings from early growth stages. This method offers a means to conduct large-scale functional genome screening in plants.