First report of Potato virus s naturally infecting arracacha (Arracacia xanthorrhiza) in Peru.
Using newly designed universal primers confirmed to amplify fragments of the RdRp region of carlaviruses from potato and sweet potato, a 340-bp band could be amplified from an asymptomatic arracacha (Arracacia xanthorrhiza) plant collected on August 2011 from a smallholder in Cajamarca, Peru. The fragment was sequenced, revealing closest nt similarity of 76% with a sequence of Potato virus S (PVS) (JQ647830.1) available in GenBank. A total of 20 arracacha accessions from the CIP Germplasm bank were then tested with the same primers and detected one positive plant (CIP204060; isolate Pasco), originally from Oxapampa, Peru, whose PCR fragment had 83% nt identity to the previous fragment isolated and 79% nt identity with a PVS sequence from GenBank (CAA75715.1). This is thought to be the first report of PVS naturally infecting arracacha in Peru.