Primers used for amplification of the tuf DNA barcode.

Two pairs of primer cocktails were used for universal amplification of the tuf barcode from all phytoplasma strains employed in this study in a nested PCR assay. Tuf 340/Tuf890 and Tuf400/Tuf835 primer cocktails were used in direct and nested PCR respectively. Each primer cocktail contained slightly different variants of the same primer mixed in equimolar amounts. The nucleotide sequences of the general sequencing primers M13F and T7 are underlined with a single and a double line, respectively. Primer positions correspond to the positions in the tuf gene of ‘Ca. P. asteris’ strain AY-WB (Genbank accession number CP000061).