Presence of “flavescence dorée” phytoplasma in grapevine lignified canes and effectiveness of different sanitation methods

Control of propagation materials in nursery for the presence of “flavescence dorée” (FD) phytoplasma, a quarantine pathogen of grapevine, is of the greatest importance to avoid long-distance spreading of FD. Three different sanitation methods were tested on Glera variety scions. Hot water treatment proved to be the best, though a few FD-infected grafted plants were found in one trial. At the same time, PCR analyses of mature canes, suitable for grafting, from infected plants in vineyard showed that lignified canes with symptomatic leaves were very infected (97.3%), while also lignified canes with asymptomatic leaves from the same Glera plants harboured FD phytoplasma (from 9.8 to 26.0%).