Detection and characterization of a phytoplasma associated with annual blue grass (Poa annua) white leaf disease in southern Italy

A phytoplasma was detected in annual blue grass (Poa annua L. Fienardo), exhibiting white leaf symptoms, that was grown in the fields near Caserta in southern Italy. Based on restriction fragment length polymorphism analysis of PCR-amplified 16S rDNA sequences, the phytoplasma associated with annual blue grass white leaf disease was identified as a new member of phytoplasma 16S rRNA group XI (16SrXI) (type strain, rice yellow dwarf phytoplasma). The annual blue grass white leaf phytoplasma is most closely related to Bermuda grass white leaf phytoplasma found in Asia. Annul blue grass white leaf and Bermuda grass white leaf phytoplasmas were designated as the third subgroup (16SrXI-C) of group XI. This is the first report that a plant pathogenic phytoplasma belonging to group 16SrXI is present on the European continent.