Rescue of the rdn1 phenotype with Medtr5g089520 (RDN1) cDNA. Mean nodule number per plant ± se on seedlings with transformed hairy roots. Nontransformed roots (DSRed negative) were trimmed off prior to inoculation. A17 with empty vector (EV), n = 18; rdn1-1 with EV, n = 25; rdn1-1 with 35Spro:RDN1, n = 10; rdn1-2 with EV, n = 25; rdn1-2 with 35Spro:RDN1, n = 38.