Self-Incompatibility (SI) is a self/non-self recognition mechanism by which pistils of flowering plants reject self-pollen to prevent inbreeding and accept non-self pollen to generate genetic diversity. In Petunia inflata, the polymorphic S-RNase gene encodes the pistil determinant, and 17 S-locus F-box (SLF) genes encode the pollen determinant. I have expressed S2-SLF13 fused with Green Fluorescent Protein in S2S3 and S2S7 transgenic plants to determine the interaction relationships between S2-SLF13 and S3-RNase and S7-RNase.