Areca palm necrotic ringspot virus, classified within a recently proposed genus 'Arepavirus' of the family Potyviridae, is associated with necrotic ringspot disease in areca palm.

Areca palm (Areca catechu L.), one of the two most important commercial crops in Hainan, China, has been severely damaged by a variety of pathogens and insects. Here, we report a new disease, tentatively referred to as areca palm necrotic ringspot disease (ANRSD), which is highly epidemic in the main growing regions in Hainan. Transmission electron microscopy observation and small RNA deep sequencing revealed the existence of a viral agent of the family Potyviridae in a diseased areca palm plant (XC1). The virus was tentatively named areca palm necrotic ringspot virus (ANRSV). Subsequently, the positive-sense single-stranded genome of ANRSV isolate XC1 was completely determined. The genome annotation reveals the existence of two cysteine proteinases in tandem (HC-Pro1 and HC-Pro2) in the genomic 5' terminus of ANRSV. Sequence comparison and phylogenetic analysis suggested the taxonomic classification of ANRSV into the recently proposed genus 'Arepavirus' in the family Potyviridae. Given the close relationship of ANRSV with the other newly reported arepavirus (ANSSV), the exact taxonomic status of ANRSV needs to be further investigated. Eventually, a reverse-transcription (RT)-PCR assay for ANRSV-specific detection was developed and a close association between ANRSV and the disease was found.