Detection of Alfalfa mosaic virus in laurustinus in Apulia

Laurustinus (Viburnum tinus L.), an evergreen shrub of the Mediterranean scrub, is widely used in Italy as an ornamental in private and public gardens. In the spring of 2014, conspicuous interveinal yellow spots and mottling were observed on the foliage of a V. tinus plant cv. Eve Price growing in the Campus of the University of Bari (Italy). Since Alfalfa mosaic virus (AMV) has been reported from V. tinus and related species (V. opulus and V. lucidum) in several countries, and in northern Italy (De Sanctis and Quacquarelli, 1985; Parrella et al., 2011), the symptomatic plant was tested by RTPCR for the presence of this virus. The specific primer set CPAMV1/CPAMV2, designed in the viral RNA3 sequence (Finetti-Sialer et al., 1997) amplified the expected 754 bp fragment, spanning the whole coat protein gene and the 3'- UTR. There was no amplification from symptomless plants. The amplified fragment was cloned into pSC-A-amp/kan, custom-sequenced (Macrogen Europe, The Netherlands) and the sequence was deposited in GenBank as accession No. KP233749. The cloned sequences were BLAST compared with those of a Chilean strain of AMV from V. tinus and a Spanish isolate from V. lucidum, with which an identity at the nucleotide level of 99% and 94%, respectively, was found. These results demonstrate the presence of an AMV strain in laurustinus in southern Italy.