MLOs are associated with a grapevine yellows disease 'Vergilbungskrankheit' in Germany
Studies have been carried out in Germany to confirm the assumption that, as in the case of other yellows diseases of grapevine, MLOs were associated with 'Vergilbungskrankheit' (VK) which is of increasing importance in some viticultural regions of Germany (e.g. Mosel valley). MLOs could be detected in tissues of symptomatic grapevines by PCR that amplified a sequence of the 16S rRNA gene. A preliminary characterization of the MLO from the infected grapevine (by RFLP) revealed a close relationship with the MLO causing stolbur disease of solanaceous plants. The authors also found that the VK agent is distinct from flavescence dorée MLO (EPPO A2 quarantine pest). This could explain some of the differences observed between these two diseases, such as susceptibility of cultivars and the non-transmission of VK by Scaphoideus titanus (vector of grapevine flavescence dorée). The authors concluded that further studies on the epidemiology of this disease and its relation with other European grapevine yellows which are not transmitted by S. titanus are needed.
Sources
Maixner, M.; Ahrens, U., Seemüller, E. (1994) Detection of mycoplasmalike organisms associated with a yellows disease of grapevine in Germany.
Journal of Phytopathology, 142 (1), 1-10.