Figure 4.

Phylogenetic analyses of 16 strains of X. albilineans spanning the genetic diversity of this species and belonging to different PFGE groups: A: MLSA dendrogram obtained with 16 strains of X. albilineans from diverse geographical origins and rooted with X. albilineans strain XaS3 (outgroup). Strain XaS3 was isolated in Guadeloupe from the surface of a sugarcane leaf and failed to induce symptoms in sugarcane after plant inoculation [16]. The tree was constructed with concatenated sequence of the PCR fragments of seven housekeeping genes (gyrB, groEL, atpD, dnaK, efp, glnA and recA) using the maximum likelihood method and GTR as substitution model. Strains on a grey background correspond to strains Xa23R1, HVO082, GPE PC73 and XaFL07-1 used for SSH comparative in silico analysis. B: PFGE groups assigned to each X. albilineans strain, data from Davis et al. (1997) [24] and Rott P. (unpublished data). PFGE groups on a grey background are groups corresponding to strains Xa23R1, HVO082, GPE PC73 and XaFL07-1 used for SSH comparative in silico analysis. C: Pathogenicity in sugarcane rated as disease severity and extent of stalk colonisation (data from [25,130]; Rott P, unpublished data): H = highly aggressive group, L = low or nonaggressive group and nd = no data. Groups on a grey background are groups corresponding to strains Xa23R1, HVO082, GPE PC73 and XaFL07-1 used for SSH comparative in silico analysis