Occurrence and Control of Cherry Stem Pitting Disease. J. K. UYEMOTO, Department of Plant Pathology, University of California, Davis 95616. J. A. GRIESBACH, Oregon Department of Agriculture, Salem 97301, and J. A. GRANT, Cooperative Extension, University of California, Davis 95616. Plant Dis. 79:366-368. Accepted for publication 20 December 1994 . This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1995. DOI: 10.1094/PD-79-0366.

Cherry stem pitting (CSP) is a debilitating disease of sweet cherry trees (Prunus avium (L.) L. ‘Bing’). Symptoms on the tree trunks include thickened bark and prominent pits in the woody cylinder. Eventually, affected trees decline. Surveys of commercial orchards, some of which were established with a mixture of cv. Bing on Colt (P. avium ? P. pseudocerasus), mahaleb (P. mahaleb L.), or mazzard (P. avium) rootstocks, revealed that disease incidence ranged up to 44% but only trees on mahaleb and mazzard rootstocks were symptomatic. All Bing/Colt trees appeared healthy, which indicated that Colt rootstock is likely resistant to the CSP agent. These observations were confirmed in test plots replicated with trees of Bing/ Colt and Bing/mahaleb. Although circumstantial evidence suggests a Soilborne origin and symp-toms resemble those of Prunus stem pitting (PSP), all attempts to detect tomato ringspot virus (the causal agent of PSP) in affected trees by graft-inoculations onto P. tomentosa Thunb. have failed