Journal of Plant Pathology Archive

Abstract:

Different aged shoots of X-disease cherry trees (Prunus avium cv Bing) collected in spring (June) or summer (August) were assayed using fruit spurs or bud chips from current, 1-, 2- and 3-year old shoots. Ten to 20 single t-grafts were made onto indicator trees of Bing scions on mahaleb (P. mahaleb) rootstocks. Spring collections, irrespective of shoot age, produced transmission rates of 10%. In contrast, over half of the indicators were infected with summer collections, which when t-bud propagated onto mazzard (P. avium) seedlings resulted in 90% diseased progeny trees. Results showed that biologic assays for cherry X-phytoplasma were optimized using summer collections. Besides cherry sources, index-transmissions and propagations of scion buds from X- and peach yellow leaf roll- (PYLR) peach trees produced high rates of transmission (both diseases) and high numbers of diseased progeny (PYLR).