FIG 3.

Role of polygalacturonase A (PglA) on Xylella fastidiosa vector transmission. (A) The pglA mutant was inoculated into artificial diets if cells were grown in medium supplemented with galacturonic acid (Gal. acid), but not with pectin. Furthermore, the transmission efficiency over time for the pglA mutant was similar to that of the wild type. The ratio of the P value and coefficient of determination (r²) for linear regressions between time and transmission efficiency for the various strains in panel A are as follows: wild type in gal. acid (0.010/0.918), pglA mutant in gal. acid (0.007/0.933), wild type in pectin (0.003/0.960), and pglA mutant in pectin (0.260/0.390). (B) The pglA mutant was not vector transmissible from plant to plant. (C and D) When artificial diets were used for pathogen acquisition, pglA cells grown in media supplemented with pectin (C) or galacturonic acid (D) were not transmitted to plants, while the wild type was transmitted in both cases.