Chemical Protection of Almond Pruning Wounds from Infection by Phytophthora syringae. M. A. Doster, Graduate Research Assistant, Department of Plant Pathology, University of California, Davis 95616. R. M. Bostock, Associate Professor, Department of Plant Pathology, University of California, Davis 95616. Plant Dis. 72:492-494. Accepted for publication 8 January 1988. Copyright 1988 The American Phytopathological Society. DOI: 10.1094/PD-72-0492.

Application of fosetyl-Al (Aliette 80WP) (3 and 30 g a.i. L^-1) to almond tree (Prunus dulcis) pruning wounds prevented the formation of pruning wound cankers caused by Phytophthora syringae and was effective during the time period that nontreated wounds were susceptible to infection. Application of cupric hydroxide (Kocide 101 77WP) (1.8, 18.3, and 740 g a.i. L^-1) to pruning wounds before inoculation with P. syringae resulted in the formation of fewer cankers than in nontreated wounds for most trials, but wounds treated with cupric hydroxide frequently showed at least one of the following signs of phytotoxicity: formation of clear gum, xylem discoloration, excessive inner bark dieback, and abnormal wound-induced lignification.