Evaluation of Wall Deposits in Phloem Cells to Detect Little Cherry Disease in Sweet Cherry Trees. J. T. Slykhuis, Research Station, Agriculture Canada. S. C. Li, Research Station, Agriculture Canada, and J. Yorston, British Columbia Ministry of Agriculture, Summerland, British Columbia V0H 1Z0. Plant Dis. 64:664-666. 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, 1980. DOI: 10.1094/PD-64-664.

Wall deposits that were stained with acridine orange were found in phloem cells of petioles from 83% of sweet cherry trees with symptoms of little cherry disease and in about 20% of trees with normal fruit. They were found in 16 of 21 trees with symptoms that indexed positive and in four of seven that indexed negative on Sam indicator trees. Wall deposits in petioles collected in late summer from trees that bore normal fruit in orchards where diseased trees had been removed in midsummer of 1977 did not correlate with the development of little cherry symptoms in 1978 or in 1979. Although frequently associated, wall deposits in petioles may not be specifically related to the little cherry disease.