Genetic variability among flavescence dorée phytoplasmas from different origins in Italy and France.
Flavescence dorée is a devastating disease of grapevine widespread in several countries in EU such as France, Italy and Spain. Genetic variability among 17 Italian and 3 French FD strains was investigated by RFLP analyses based on a fragment of the ribosomal protein operon and on the non-ribosomal DNA fragment FD9. RFLP analysis of the PCR amplified ribosomal protein fragment, coding for the 3' end of rpl22 and the entire rps3 genes, differentiated 4 rp-subgroups among the FD strains and 4 subgroups among the reference strains belonging to elm yellows group (16SrV). Sequencing and phylogenetic analysis of the same ribosomal protein DNA fragment validated the delineation of 4 distinct FD strain types derived by RFLP analyses. The results supported the differentiation based on analysis of the non-ribosomal DNA fragment FD9. The phylogenetic analysis further revealed relationships and a probable evolutionary trend among the FD strains and the other representatives of elm yellows group. All the FD strains together with the reference strains ALY, RuS and JWB formed a cluster very well distinct from the EY/ULW cluster. Moreover, ALY was shown to be more closely related to three FD strain types: the Lombardia/Piemonte, the French FD70, and the French FD88/Italian FD-D strain clusters.
Martini
M
M
DiSTA, Patologia Vegetale, University of Bologna, Italy.
Botti
S
S
Marcone
C
C
Marzachì
C
C
Casati
P
P
Bianco
P A
PA
Benedetti
R
R
Bertaccini
A
A
D004269:DNA, Bacterial / Q000032:analysis; D004275:DNA, Ribosomal / Q000235:genetics; D005602:France; D014644:Genetic Variation; D007558:Italy; D008969:Molecular Sequence Data; D009174:Mycoplasma / Q000145:classification / Q000235:genetics*; D009876:Operon; D010802:Phylogeny; D010935:Plant Diseases / Q000382:microbiology*; D012150:Polymorphism, Restriction Fragment Length; D016415:Sequence Alignment; D027843:Vitis / Q000382:microbiology*
D004269:DNA, Bacterial; D004275:DNA, Ribosomal