Virescence of tenweeks stock associated to phytoplasma infection in Sicily

In April 2007, a severe disease occurred in Sicily (Italy) in a glasshouse cultivation of tenweeks stock belonging to the cultivar White-Beach. Plants were stunted and rosetted, and the flowers were of small size and characterized by virescence symptoms. Phytoplasma presence and identity was detected by applying PCR/RFLP techniques and sequencing of 16S ribosomal gene. Phytoplasmas were identified as belonging to ribosomal subgroup 16SrII-A, never reported before in Italy and showed 99% of homology with 'Candidatus Phytoplasma aurantifolia' and related phytoplasmas. This is the first report of a phytoplasma disease of tenweeks stock. Considering that this Brassicaceae ornamental species is widely grown in Italy, it could play an important role in spreading these phytoplasmas, new for Italy.