Invasive Species Compendium

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Abstract

First report of pepper cryptic virus 2 infecting pepper (Capsicum annum) in Slovakia.

Abstract

In an effort to unravel the virome present in a symptomatic sweet pepper (C. annuum) from western Slovakia (locality Čachtice), a plant of cultivar Promotor (coded N65) showing leaf chlorosis, mottling, and deformation was sampled in August 2017 and subjected to high-throughput sequencing (HTS). BLASTn analysis of the generated contigs (~16,000 contigs >500 bp) revealed a complex viral infection involving cucumber mosaic virus (CMV), watermelon mosaic virus, bell pepper endornavirus, and pepper cryptic virus 2 (PCV-2). Because PCV-2 was previously unreported from the central European region, to confirm its presence in the N65 plant and to assess further the virus presence in Slovakia, 35 leaf samples obtained from various symptomatic sweet pepper and chili plants were tested in 2018 and 2019 by reverse transcription PCR (RT-PCR). BLASTn analysis indicated that all the Slovak PCV-2 isolates shared high nucleotide identity (97 to 100%) with the corresponding portions of N65 isolate, resulting in low average nucleotide divergence (0.1% for RNA1 and 0.5% for RNA2). Fifteen PCV-2-infected pepper and chili samples were further tested for the presence of two main common pepper viruses in Slovakia: CMV and potato virus Y (PVY). Both RT-PCR and double antibody sandwich ELISA tests revealed mixed PCV-2/PVY (n=9), PCV-2/CMV (n=2), or PCV-2/PVY/CMV (n=4) infections. As a consequence, the symptoms observed (mosaics, leaf mottling, and deformations) could not be attributed to a particular virus or to synergism between these viruses. This is thought to be the first report of PCV-2 infection of pepper in Slovakia.