Molecular characterization of 16SrII-D phytoplasmas infecting tomato

Nucleic acid samples from tomato plants exhibiting witches’ broom symptoms were employed to characterize the identified phytoplasmas at a multigene level. Preliminary assays using PCR, restriction fragment length polymorphism analyses and sequencing on a fragment of the 16S rRNA gene allow the clustering of this phytoplasma within strains classified in subgroup 16SrII-D. Furthermore, RFLP characterization of phytoplasma tuf and rp genes confirmed that the restriction patterns of phytoplasmas from tomato samples were identical to each other and to those of strains in subgroup 16SrII-D. A primer pair designed on a RAPD amplicon sequence from a 16SrII-A phytoplasma strain resulted to specifically amplify the DNA of the tomato samples as well as phytoplasma strains in subgroups 16SrII-A and 16SrII-D specifically detecting and identifying the presence of this phytoplasma. This fragment could be useful for the rapid screening of the presence of this phytoplasma in tomato and other crops of economic importance.