Table I. Distributional comparison of X. fastidiosa in some exemplary 12-week-postinoculated grapevines with different PD resistances.
The absence or presence of bacterial cells was examined in both inoculated and noninoculated shoots of PD-susceptible grapevine var. Chardonnay (Chardonnay) and grapevine var. Riesling (Riesling) as well as in shoots of PD-resistant V. arizonica X rupestris (89-0908) and V. vinifera X arizonica (U0505-01).
| Internodea | Chardonnay (PD Susceptible) |
Riesling (PD Susceptible) |
89-0908 (PD Resistant) |
U0505-01 (PD Resistant) |
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| Inoculated Shootb | Noninoculated Shoot | Inoculated Shoot | Noninoculated Shoot | Inoculated Shoot | Noninoculated Shoot | Inoculated Shoot | |
| 1 | +c | + | − | − | − | − | − |
| 3 | + | − | + | + | + | − | − |
| 5 | + | + | + | − | + | − | + |
| 7 | + | + | + | + | − | − | − |
| 9 | + | + | − | + | − | − | − |
| 11 | + | + | + | + | − | − | − |
| 13 | + | + | + | + | − | − | − |
| 15 | + | − | + | + | − | − | N/A |
| 17 | + | + | + | + | − | N/A | N/A |
| 19 | + | + | N/A | + | N/A | N/A | N/A |
| 21 | + | N/Ad | N/A | − | N/A | N/A | N/A |
| 23 | + | N/A | N/A | N/A | N/A | N/A | N/A |
a
Internodes are numbered from each shoot base upwards with the first internode at the base as internode 1.
b
Inoculation site was at the sixth internode from the shoot base in all the genotypes except U0505-01 that was inoculated at the fourth internode.
c
+ or − indicates that Xylella cells were observed or not observed in a specific internode.
d
N/A represents unavailability of a specific internode due to the short shoot.