NIN and infection: As expected, the application of SymCEP7 to the roots of nin, dmi2, or cra2 failed to increase nodule number (Supplemental Figure 2B), whereas in the wild type, SymCEP7 application to the roots increased the number of nodules (Figure 2C; Supplemental Figure 2B) as well as infection threads and infection pockets (Supplemental Figure 4A–C).