VIEW ARTICLE

Physiology and Biochemistry

Evidence for Xylem Dysfunction by Embolization in Dutch Elm Disease. Dennis Newbanks, Harvard University, Cabot Foundation, Petersham, MA 01366; Arjen Bosch(2), and Martin H. Zimmermann(3). (2)(3)Harvard University, Cabot Foundation, Petersham, MA 01366. Phytopathology 73:1060-1063. Accepted for publication 5 January 1983. Copyright 1983 The American Phytopathological Society. DOI: 10.1094/Phyto-73-1060.

Conducting vessels of elm seedlings were stained by dye uptake from a vacuum container during transpiration. Nonconducting vessels remained unstained or their walls were only stained where in direct contact with conducting vessels. The staining pattern of the vessel network was analyzed by shuttle microscopy over distances of 1,000 transverse sections, spaced 0.1 mm. Nonconducting vessels in infected stems were thus identified before any other visible effect, such as entry of hyphae or gums, could be detected.