VIEW ARTICLE

Peach Stem Pitting: Transmission and Natural Spread. Srecko M. Mircetich, Research Plant Pathologist, Crops Research Division, ARS, USDA, Beltsville, Maryland 20705; H. W. Fogle(2), and E. L. Civerolo(3). (2)(3)Horticulturist, and Research Plant Pathologist, respectively, Crops Research Division, ARS, USDA, Beltsville, Maryland 20705. Phytopathology 60:1329-1334. Accepted for publication 23 March 1970. DOI: 10.1094/Phyto-60-1329.

Peach stem pitting was transmitted by buds or root chips from naturally infected peach trees into peach seedlings in both greenhouse and nursery experiments. Pitting and grooving of the lower trunk, resembling that in naturally infected trees, developed in the inoculated peach seedlings within 12 months after inoculation. Apricot seedlings on Elberta peach seedling rootstocks and inoculated with buds from naturally infected peach trees did not pit, but the peach rootstock developed typical symptoms. Natural spread of peach stem pitting was demonstrated by annual surveys in a densely planted peach seedling orchard. Typically, disease spread from an infected tree to adjacent healthy trees, and no random occurrence of newly infected trees in the orchard was observed. Attempts to transmit a virus mechanically from naturally infected peach trees to various herbaceous plants failed. The relation of peach stem pitting to pitting in other Prunus spp. is discussed.