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In the neighbouring regions Basilicata, Campania, and Calabria of southern Italy, diseased trees of European field elm (Ulmus minor) were examined for phytoplasmal infection using polymerase chain reaction (PCR) technology. All affected trees examined tested positively. Using a primer pair specific for the EY phytoplasma group and restriction fragment length polymorphism (RFLP) analysis of PCR‐amplified ribosomal DNA, the organism detected was identified as the elm yellows (EY) phytoplasma. RFLP analysis of PCR‐amplified ribosomal DNA was also employed to attempt differentiation within the EY group which includes, in addition to the EY agent, phytoplasmas infecting Rubus, alder, eucalypts, Spanish broom, and grapevine. Following separate digestion with AluI, RsaI, Sau3AI, MseI, HhaI, and KpnI, all PCR‐products from EY‐group phytoplasmas examined had similar RFLP profiles. When the same …