VIEW ARTICLE

Ecology and Epidemiology

Late Season Water Deficits and Development of Cytospora Canker in French Prune. P. F. Bertrand, Research Assistant, Department of Plant Pathology, University of California, Davis 95616, Present address of senior author: Oregon State University, Mid-Columbia Experiment Station, Rt. 5, Box 240, Hood River, Oregon 97031; Harley English(2), K. Uriu(3), and F. J. Schick(4). (2)Professor, Department of Plant Pathology, University of California, Davis 95616; (3)Pomologist, Department of Pomology, University of California, Davis 95616; (4)Research Associate, Department of Plant Pathology, University of California, Davis 95616. Phytopathology 66:1318-1320. Accepted for publication 28 February 1976. Copyright © 1976 The American Phytopathological Society, 3340 Pilot Knob Road, St. Paul, MN 55121. All rights reserved.. DOI: 10.1094/Phyto-66-1318.

French prune trees subjected to postharvest moisture stresses developed significantly larger cankers following inoculation with mycelium of Cytospora leucostoma than did adequately irrigated trees. Tree water status was monitored in terms of (i) relative water tension with a pressure chamber and (ii) percent bark moisture. The pressure chamber gave a more sensitive evaluation of tree water status and provided data that correlated well with canker development.