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

Abstract

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.

Biological and Molecular Characterization of Two Closely Related Arepaviruses and Their Antagonistic Interaction in Nicotiana benthamiana

“…The determination of the complete genome sequence of ANRSV-ZYZ was essentially the same as that of previously reported ANRSV-XC1 ( Yang et al, 2019 ). In brief, nine overlapping fragments covering nearly the whole genome were cloned and sequenced.…”

“…The 5′- or 3′-terminal cDNAs of ANRSV-ZYZ were obtained using 5′ or 3′ RACE kits (Invitrogen). The cloning and sequencing of these resulting polymerase chain reaction (PCR) products were essential, as described previously ( Yang et al, 2019 ).…”

“…Arepavirus is a newly established genus under the family Potyviridae and consists of two virus species, namely, areca palm necrotic spindle-spot virus (ANSSV) and areca palm necrotic ringspot virus (ANRSV) ( Wylie et al, 2017 ; Yang et al, 2018 , 2019 ; Cui and Wang, 2019 ). The two viruses exhibit a distinctive organization in the genomic 5′-terminus that encodes a unique pattern of leader proteases, that is, two cysteine proteases in tandem (HCPro1–HCPro2) ( Qin et al, 2021 ).…”

“…The two viruses exhibit a distinctive organization in the genomic 5′-terminus that encodes a unique pattern of leader proteases, that is, two cysteine proteases in tandem (HCPro1–HCPro2) ( Qin et al, 2021 ). It has been highlighted that both viruses share 76.2 and 88.6% amino acid (aa) identities at the large polyprotein and coat protein (CP) levels, respectively ( Yang et al, 2019 ). In addition, the ANRSV is highly prevalent with an average incidence rate of 19% in the field and is associated with severe necrotic ringspot symptoms.…”

Assessment of the Spatial Distribution and Risk Associated with Fruit Rot Disease in Areca catechu L.

“…Although the production of arecanut is confined to a few states, commercial products are extensively exported across the globe, and approximately 700 million people are dependent on arecanut worldwide [7,8]. Being a perennial crop, arecanut is highly vulnerable to numerous pathogens, including fungi [9][10][11], bacteria [12], phytoplasma [13][14][15], and viruses [16][17][18].…”