Lobelia (Lobelia erinus L.) is a common herbaceous annual used in flower beds and hanging baskets. The plant blooms from early to late summer. In the summer of 2000, Lobelia plants expressing virus-like symptoms were collected from a greenhouse-based production site in Ohio. Affected plants expressed a mild leaf mosaic and stunting. Viral-associated dsRNA was isolated from 7 g of symptomatic leaf tissue (1). Four dsRNAs were observed at 3.9, 3.0, 2.25, and 1.05 kb indicating the presence of a Cucumovirus. A fifth dsRNA at 0.75 kb also was observed, consistent with the presence of a satellite RNA. Enzyme-linked immunosorbent assay (ELISA) analysis (Agdia, Inc., Elkhart, IN) of symptomatic Lobelia tissue confirmed the presence of Cucumber mosaic virus (CMV). A (S)CARNA-5 (-) cDNA clone (American Type Culture Collection #45124) was labeled with digoxygenin (DIG) as per the manufacturer's instructions (Genius II DIG-DNA Labeling Kit, Boehringer Mannheim) and used as a diagnostic probe to detect this satellite RNA. Northern hybridization confirmed the identity of the satellite RNA (2). This is the first report of any satellite RNA associated with a virus infection in Lobelia and the first report of CMV in this host in Ohio.
References: (1) J. R. Fisher and S. G. P. Nameth. HortScience 35:230--234, 2000. (2) R. A. Valverde et.al. Plant Dis. 74:255--258, 1990.