Isolation of Cherry Leaf Roll and Brome Mosaic Viruses from European Beech and Transmission to Beech Seedlings. JOACHIM HAMACHER, Associate Professor, Institute fur Pflanzenkrankheiten, Rheinische Friedrich-Wilhelms-Universitat, Nussallee 9, 53115 Bonn, Germany. ANDREA QUADT, Research Associate, Institut fur Pflanzenkrankheiten, Rheinische Friedrich-Wilhelms-Universitat, Nussallee 9, 53115 Bonn, Germany. Plant Dis. 78:849-853. Accepted for publication 16 May 1994. Copyright 1994 The American Phytopathological Society. DOI: 10.1094/PD-78-0849.

Cherry leaf roll virus (CLRV) and brome mosaic virus (BMV) were transmitted from foliage of European beech to herbaceous plants and then back-transmitted to beech seedlings. Beech sampling sites were located in a nature reserve in Northrhine-Westfalia for CLRV and near the village of Hilberath, between the borders of the states of Rhineland-Pfalz and Northrhine-Westfalia, for BMV. Viruses were identified by bioassay, enzyme-linked immunosorbent assay, and immune electron microscopy. Transmission succeeded when seedlings in the four-leaf stage were inoculated by stem slashing. Infection rates averaged 24% for BMV and 17% for CLRV. Injection of concentrated BMV suspension into stratified beechnuts resulted in 15% infected seedlings 1 yr after infection. Symptoms developed in some inoculated beech seedlings about 4 wk after inoculation. Electron microscopy of infected tissue showed ultrastructural alterations.