Observation of phytoplasmas in grapevines affected by a yellows disease in Italy
Electron microscopy studies have been carried out in Italy on tissues from Vitis vinifera plants grown in Emilia-Romagna, and naturally infected with a yellows disease similar to grapevine flavescence dorée phytoplasma (EPPO A2 quarantine pest). In this region, though the symptoms are similar to flavescence dorée, its vector (Scaphoideus titanus) is not present. Pleomorphic phytoplasmas were clearly seen, in varying concentrations, in mature sieve tube elements of leaf veins. These results support the phytoplasma-like etiology of the grapevine yellows observed in Emilia-Romagna.
Credi, R. (1994) Mycoplasma-like organisms associated with a grapevine yellows disease occurring in Italy.
Journal of Phytopathology, 141(2), 113-224.