Poster: Diseases of Plants: New & Emerging Diseases
Viral metagenomics of Caladium x hortulanum (Araceae) in Florida
R. ALCALA BRISEÑO (1), M. Londoño (1), J. Polston (1); (1) University of Florida, U.S.A.
Viral metagenomics and high-throughput sequencing were used to identify novel viruses present caladiums (Caladium x hortulanum, Araceae), collected from Lake Placid, Florida in 2013. Caladium cultivars showing viral-like symptoms were sequenced, reads were assembled and contigs were analyzed using BLASTX showing homology with viral species in the Potyviridae, Rhabdoviridae and Caulimoviridae. The bioinformatic results were validated by reverse transcription (RT)-PCR for RNA viruses and PCR for DNA viruses. Only two potyvirus species, Dasheen mosaic virus (DsMV), and Konjac mosaic virus (KoMV) were able to be confirmed by RT-PCR amplification and sequencing of the coat protein region (CP). DsMV was previously reported from caladium in Florida, however this is the first report of KoMV in Florida as well as North America. In order to explore the abundance and diversity of these viruses, 315 plants from 15 caladium cultivars were screened using RT-PCR with CP primers. DsMV was present in 69.5% of tested plants and in all cultivars. KoMV was present in 11% of tested plants, and in eight out of 15 cultivars. Sixty-one and thirteen CP sequences of DsMV and KoMV were sequenced, respectively. Pairwise comparison analysis indicated sequence similarity of 87.4% and 96.5% among isolates of DsMV and KoMV, respectively. The low diversity, abundance and phylogenetic analysis are consistent with a single introduction event for both DsMV and KoMV.