Fig. 7. Longitudinal mosaic of peach stem inoculated with L. persoonii. Note masses of hyphae in periderm and cortical regions (large arrows) and in the gum duct zone of the newly differentiated xylem (small arrows). Colonization proceeding from top to bottom. Note gum (G), vascular cambium (VC), and dark deposits in older xylem. The vascular cambium in this region will redifferentiate into a suberized periderm-like layer. x420.