15 research outputs found
Multilocus sequence analysis reveals the genetic diversity of European fruit tree phytoplasmas and the existence of inter species recombination
Multilocus sequence analysis reveals the genetic diversity of European fruit tree phytoplasmas and supports the existence of inter-species recombination
The genetic diversity of three temperate fruit tree phytoplasmas ‘Candidatus Phytoplasma
prunorum’, ‘Ca. P. mali’ and ‘Ca. P. pyri’ has been established by multilocus sequence analysis.
Among the four genetic loci used, the genes imp and aceF distinguished 30 and 24 genotypes,
respectively, and showed the highest variability. Percentage of substitution for imp ranged from 50
to 68% according to species. Percentage of substitution varied between 9 and 12% for aceF,
whereas it was between 5 and 6% for pnp and secY. In the case of ‘Ca P. prunorum’ the three
most prevalent aceF genotypes were detected in both plants and insect vectors, confirming that
the prevalent isolates are propagated by insects. The four isolates known to be hypo-virulent had
the same aceF sequence, indicating a possible monophyletic origin. Haplotype network
reconstructed by eBURST revealed that among the 34 haplotypes of ‘Ca. P. prunorum’, the four
hypo-virulent isolates also grouped together in the same clade. Genotyping of some Spanish and
Azerbaijanese ‘Ca. P. pyri’ isolates showed that they shared some alleles with ‘Ca. P. prunorum’,
supporting for the first time to our knowledge, the existence of inter-species recombination
between these two species