First report of Canna yellow mottle virus (CaYMV) in Italy and in The Netherlands

During 2005 a survey was done to investigate a yellow mottling of Canna sp. observed in some gardens in Campania and Latium, Italy and in some nurseries in The Netherlands. Symptoms consisted of veinal yellowing and chlorotic mottle of leaves (Fig. 1) often combined with streaking of the stem and flowers (Fig. 2). These symptoms are similar to those described for Canna yellow mottle, a disease reported in North America and Japan (Yamashita, 1985; Lockhart, 1988, Momol et al., 2004) and associated with Canna yellow mottle virus (CaYMV), a Badnavirus of the family Caulimoviridae, often found in mixed infection with Cucumber mosaic virus (CMV) and an unidentified flexuous rod-shaped virus (Lockhart, 1988). Extracts from 12 Canna plants (8 from Italy and 4 from The Netherlands) with and without symptoms were checked by transmission electron microscopy and immunosorbent electron microscopy, using a broad spectrum antiserum (Nodwora and Lockhart, 2000), which revealed the presence of badnavirus-like particles in 11/12 plants (8 from Italy and 3 from The Netherlands) with and in 3/4 plants without symptoms.

CaYMV presence in plants both with and without symptoms was confirmed by PCR using CaYMV-specific primers (Momol et al., 2004) that amplified a product of expected size (565 bp). Sequences of PCR products from the Italian plants were deposited in GenBank (Accession Nos. EF156357 to EF156364) and compared with the original CaYMV sequence (Momol et al., 2004) to which they had a > 96% similarity. Many samples containing CaYMV were also found to be infected with a potyvirus which is being characterized. To our knowledge, this is first report of the occurrence of CaYMV in Italy and The Netherlands.