Southward Spread of Pepper Necrotic Spot Orthotospovirus into Chile: Identification and Characterization

During the 2020 through 2024 growing seasons, pepper fruits exhibiting symptoms typically associated with spotted wilt were observed in the Arica y Parinacota region, in northern Chile. As this region is a key winter supplier of vegetables to southern Chile, the present study aimed to identify and characterize orthotospoviruses infecting local pepper crops. Species-specific and generic primers targeting orthotospoviruses were used in RT-PCR assays for virus identification, and thrips vectors were characterized both morphologically and by PCR using ITS- and MtCOI-specific primers. Tomato spotted wilt virus (TSWV; Orthotospovirus tomatomaculae) and the putative new orthotospovirus, pepper necrotic spot virus (PNSV) were detected in samples collected from four production fields in Arica y Parinacota. Among the known orthotospovirus vectors, only Frankliniella occidentalis was identified at sampled sites. While TSWV is already endemic in Chile, this represents the first report of PNSV in the country. Given that PNSV has been previously reported in Peru, the geographic proximity of Arica y Parinacota raises concern for its continued southward spread into Chile. This finding underscores the need for further epidemiological studies on PNSV and the development of strategies to mitigate its dissemination within the country.