Flavescence dorée is a severe grapevine disease in Europe, due to a phytoplasma vectored by the Cicadellidae Scaphoideus titanus. The Flavescence dorée (FD) phytoplasma is classified as a quaran-tine organism and mandatory pest control has been implemented, consisting of uprooting diseased plants, insecticide treatments against the vector and planting healthy plants. Unfortunately, the dis-ease still spreads in Europe and alternative measures are needed. No grapevine resistant to FD has been discovered but there are differences in susceptibility, based on the proportion of infected plants, symptoms and phytoplasma titers. The use of poorly susceptible grapevine cultivars reduces the spread of the disease in vineyards and could be a complementary control measure. To understand better grapevine susceptibility and to look for sources of low susceptibility to FD, we evaluated fourty Vitis vinifera, rootstocks, new hybrid varieties and wild Vitis genotypes in controlled conditions after insect-mediated transmission of the FD phytoplasma. By measuring the proportion of infected plants and the phytoplasma titers, we characterized a range of susceptibilities with con-trasted phenotypes. In particular, by testing the genealogy of Merlot, we made the hypothesis that its poor susceptibility could originate from its mother Magdeleine Noire des Charentes (Mag). To verify this hypothesis, we obtained progenies from crosses with Cabernet Franc (MagxCF, CFxMag) or from self-pollination (MagxMag), and determined the FD susceptibility of a first set of 63 siblings. Our data suggest the transmission and segregation of two traits brought by the Magdeleine in the progeny: resistance to infection and resistance to FD phytoplasma multiplication. Eight poorly sus-ceptible siblings have been transferred and kept in conservatories. New source of low susceptibility to FD phytoplasma have also been sought.< Réduire