Peanut stripe potyvirus (PStV) has been taxonomically classified as a strain of bean common mosaic virus (BCMV) that infects peanut (groundnut). PStV is spread by aphids and is seedborne in peanut and soybean. Disease incidence and yield losses are high where PStV is endemic. Infected plants display a wide range of leaf symptoms dependent on virus isolate, peanut cultivar and time of infection. These symptoms can overlap with those caused by other viruses that are known to infect peanut, making definitive diagnosis of stipe disease difficult on the basis of symptoms alone. A set of criteria has been developed to assist in the identification of PStV. Biologically distinct isolates have been collected in Indonesia and China and their effect on yield and quality of peanuts, seed transmission rates and pathogenicity has been quantified. PStV isolates cannot be differentiated by serology, but nucleotide sequences of the CP gene and 3’UTR are good discriminators. In a neighbour joining tree of CP nucleotide sequences, all PStV isolates form a closely related cluster with a predicted common ancestor, clearly separated from other strains of BCMV. The isolates are related according to their geographic origin, independent of the symptom type they induce on peanut which indicates that symptomatology is not determined by the CP. Sequence variation reaches up to 3.5% within and 7.3% between geographic groups. Only the Indonesian isolates of PStV appear to be recombinants with another strain of BCMV in the CP/3’UTR junction. PStV appears to have arisen independently in different locations which may happen again in the future.
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