This first photo (Alberto Bressan next to vine) shows "typical" PD symptoms up from the point of inoculation towards the tip of the cane.
For unknown reasons, different vines of the same age, location, and variety will develop somewhat different symptoms.
Here are photos taken in late July 2001 of Merlot vines inoculated with Xylella fastidiosa in April 2001.
(All photos on this page by A.H. Purcell)
This first photo (Alberto Bressan next to vine) shows "typical" PD
symptoms up from the point of inoculation towards the tip of the cane.
The second photo shows leaf discoloration spread almost evenly
throughout the leaf and without distinctive marginal leaf scorching.
The third and final photo shows a rapid and severe scorching with no
yellowing and little reddening preceding the killing and drying of the
margin of the leaf.
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