Orthotospovirus disease epidemic: molecular characterization and incidence in peanut crops

DE BREUIL, SOLEDAD; DOTTORI, CAROLINA; BEJERMAN, NICOLÁS; NOME, CLAUDIA; GIOLITTI, FABIÁN; LENARDON, SERGIO

JOURNAL OF PLANT PATHOLOGY

EDIZIONI ETS

Año: 2020

1125-4653

Argentina is one of the main peanut (Arachis hypogaea L.) exporting countries with the major peanut-growing area located in theprovince of Córdoba. During the 2015?2016 growing season, severe outbreaks of an orthotospovirus-like disease occurred in anumber of commercial peanut fields. The aim of this work was to determine the prevalence of orthotospoviruses and theirincidence in peanut. In DAS-ELISA, all samples collected from symptomatic plants reacted with antisera to groundnut ringspotvirus/tomato chlorotic spot virus (GRSV/TCSV) and tomato spotted wilt virus (TSWV). RT-PCR was performed with a singlepair of primers for conserved regions of the GRSV, TCSV and TSWV nucleoprotein (N) genes, and digestion with restrictionenzymes, allowed the identification of the pathogen as GRSV. The results were confirmed by sequencing of the N gene. Diseasedpeanut plants were observed in 30 out of 81 surveyed fields located in the north-central region of the peanut-growing area. In thatregion, the disease incidence was evaluated in four commercial fields, recorded values from 3% to 47.25% with a mean diseaseincidence of 18.69%. Our study reported for the first time a significant outbreak of GRSV in peanut in Argentina and provideinformation on the occurrence and distribution of some Orthotospovirus species.