First Report of Alfalfa mosaic virus in Viburnum lucidum in Spain.

Abstract

Viburnum sp. is an ornamental shrub widely used in private and public gardens. It is common in natural wooded areas in the Mediterranean Region. The genus includes more than 150 species distributed widely in climatically mild and subtropical regions of Asia, Europe, North Africa, and the Americas. In January 2007, yellow leaf spotting in young plants of Viburnun lucidum was observed in two ornamental nurseries in the Mediterranean area of Spain. Symptoms appeared sporadically depending on environmental conditions but normally in cooler conditions. Leaf tissue from 24 asymptomatic and five symptomatic plants was sampled and analyzed by double-antibody sandwich (DAS)-ELISA with specific polyclonal antibodies against Tomato spotted wilt virus (TSWV) (Loewe Biochemica, Sauerlach, Germany) and Alfalfa mosaic virus (AMV) (SEDIAG S.A.S, Longvic, France). All symptomatic plants of V. lucidum were positive for Alfalfa mosaic virus (AMV). The presence of AMV was tested in the 29 samples by one-step reverse transcription (RT)-PCR with the platinum Taq kit (Invitrogen Life Technologies, Barcelona, Spain) using primers derived from a partial fragment of the coat protein gene of AMV (2). The RT-PCR assays produced an expected amplicon of 700 bp in the five symptomatic seropositive samples. No amplification product was observed when healthy plants or a water control were used as a template in the RT-PCR assays. One PCR product was purified (High Pure PCR Product Purification Kit; Roche Diagnostics, Mannheim, Germany) and directly sequenced (GenBank Accession No. EF427449). BLAST analysis showed 96% nucleotide sequence identity to an AMV isolate described from Phlox paniculata in the United States (GenBank Accession No. DQ124429). This virosis has been described as affecting Viburnum tinus L. in France (1). To our knowledge, this is the first report of natural infection of Viburnum lucidum with AMV in Spain, which might have important epidemiological consequences since V. lucidum is a vegetatively propagated ornamental plant.