First Report and Molecular Identification of Pepper Mottle Virus (PepMoV) in Hot Pepper Fields

Abstract

Pepper mottle virus (PepMoV), a member of the genus Potyvirus (family Potyviridae), is an aphid-transmitted RNA virus of significant phytopathological importance capable of inducing severe mosaic patterning, leaf distortion, chlorotic mottling, necrotic streaking, fruit deformation, and substantial marketable yield reductions in hot pepper (Capsicum annuum L.) and related solanaceous crops under conditions of high aphid vector pressure and widespread susceptible cultivar deployment. Although PepMoV has been documented in several pepper-producing regions worldwide, its occurrence in numerous geographically distinct hot pepper production areas remains unreported, and the molecular diversity of circulating PepMoV isolates across newly affected production zones has not been characterized sufficiently to inform diagnostic protocol development or resistance breeding program target selection. This study reports the first confirmed occurrence of PepMoV in commercial hot pepper fields through comprehensive field surveillance, biological characterization, and multilocus molecular identification of recovered virus isolates. Systematic field surveys were conducted across major hot pepper production areas, and symptomatic plants exhibiting mosaic, mottle, leaf curl, and vein banding symptoms were systematically sampled for laboratory analysis. Mechanical inoculation assays on diagnostic host plant species within the families Solanaceae, Chenopodiaceae, and Cucurbitaceae were performed to characterize the host range and symptomatology of recovered isolates under controlled greenhouse conditions. Serological detection using potyvirus-group specific and PepMoV-specific antiserum in enzyme-linked immunosorbent assay confirmed initial virus identification. Molecular characterization was accomplished through reverse transcription polymerase chain reaction amplification of coat protein, cylindrical inclusion, and nuclear inclusion b gene regions using species-specific and genus-degenerate primer pairs, with amplified products subjected to direct Sanger sequencing.