Analyses of orthotospovirus populations and dispersion under different environmental conditions in Brazil and in the Dominican Republic

Abstract

Orthotospoviruses (genus Orthotospovirus, family Tospoviridae) are amongst the most devastating plant viruses worldwide, causing severe damage to many economically important vegetable crops, such as tomato and sweet pepper. Monitoring virus populations is an important step for estimating virus damage and epidemiology, and gaining insights into the adaptation processes undergone by orthotospoviruses. Here, we studied the orthotospovirus populations infecting vegetable crops in Brazil and the Dominican Republic, including species diversity, genome comparison and phylogenetic analyses. Comparisons of virus populations showed that in Brazil, which is considered a center of orthotospovirus diversity, groundnut rinspot virus (GRSV) is prevalent, infecting 41% of the plants, whereas tomato spotted wilt virus (TSWV) and tomato chlorotic spot virus (TCSV) were present in 4% and 9% of the samples, respectively. In the Dominican Republic, which can be considered an environment with low orthotospovirus diversity, 55% of the samples were infected with TSWV, 11% showed TCSV infection and no GRSV was detected. The occurrence of mixed infection was low in Brazil, at only 5%, but no mixed infection was detected in the Dominican Republic. The low rates of mixed infections may prevent the emergence of genomes resulting from reassortment. Indeed, no reassortant viruses were detected in either country, except for TCSV, recently proposed as representing a reassortant orthotospovirus species.

Survey of viruses and vectors in tomato plants, alternative hosts and weeds in the state of Santa Catarina, Brazil

“…This pattern was also found by Martínez et al. (2019), in a study that analysed the TCSV and GRSV populations in Brazil and the Dominican Republic.…”

“…Interestingly, the complete sequence of the TCSV M segment (isolate RDS31) revealed that it was equally similar to that of isolates SA-05 of GRSV and BR-03 of TCSV, thus corroborating the results obtained by Silva et al (2019), where both isolates were compared and it was revealed that they share the same M segment, thereby concluding that TCSV may have incorporated the GRSV M segment through a reassortment event. This pattern was also found by Martínez et al (2019), in a study that analysed the TCSV and GRSV populations in Brazil and the Dominican Republic.…”

“…Groundnut ringspot virus is the most abundant species of the spotted wilt disease complex in the midwestern and north‐eastern regions of Brazil (Ávila et al., 1996; Martínez et al., 2019; Nagata et al., 1995). However, our results reveal a different pattern in the state of Santa Catarina, with the predominance of TCSV.…”

“…To date, the orthotospoviruses CSNV, zucchini lethal chlorosis virus (ZLCV), TSWV, TCSV, GRSV, iris yellow spot virus (IYSV) (Bezerra et al, 1999), and bean necrotic mosaic virus (BeNMV) have been reported in Brazil (de Oliveira et al, 2012). Among these, GRSV is the most abundant in the horticultural regions of midwestern and north-eastern Brazil (Martínez et al, 2019). Furthermore, insect vector surveys have been conducted in Brazil.…”

La Peste Negra Del Tomate Y Morrón: Aportes Experimentales Para Su Manejo Integrado

“…Vinculado con lo anterior, se comprobó que algunas de las nuevas especies, corresponden a eventos naturales de reordenamiento, en los que, virus muy relacionados intercambian información genética aumentando su diversidad (Qiu et al, 1998;Martínez et al, 2019) y formaría parte de una adaptación evolutiva a huéspedes, vectores y zonas geográficas (Tsompana et al, 2005;Tentchev et al, 2011). Eso explicaría por qué el genoma de algunos aislados de TCSV está compuesto por los segmentos L y S de GRSV y uno M propio, que a su vez tiene alta homología con el correspondiente de GRSV (Qiu et al, 1998;Webster et al, 2011;de Breuil et al, 2016).…”