First report of natural infection of beetroot with Beet soil-borne virus.
A symptomatic beetroot sample was collected in October 2018 from a small field (c. 200 m2) in Rhineland-Palatinate, Germany, where several plants displayed virus-like symptoms. The sample submitted displayed necrosis, reduced size and in particular root proliferation (bearding) resembling the symptoms of rhizomania. Results of RNA sequence analysis revealed two causal agents, i.e. Beet soil-borne virus (BSBV) and Beet cryptic virus-2 (BCV-2). The sequences of the BSBV and BCV-2 isolates were submitted to Genbank (MK731954-MK731959). Sequence analysis revealed that the BSBV isolate shares 97.3-98.5% nucleotide identity with the reference genome (German isolate NC_003518-NC_003520). The BCV-2 isolate shares 98.7-99.7% nt nucleotide identity with the reference genome (Hungarian isolate NC_038845-NC_038847). This work provides the first suggestion that BSBV naturally infects beetroot.