Xylella fastidiosa bacteria, causal agent of CVC,
in the interior of a xylem
vessel of a Rangpur lime citrus root. Transveral section above, 11,000X and
longitudinal section below, 3,000X. The presence of the bacteria in this root system
indicates their descending, longitudinal translocation in the xylem, since inoculation
occurred in the aerial parts of the plant. Ascendant translocation, however, is
probably many times more efficient, being the normal direction of flow of xylem sap.
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