Biological and molecular properties of Tomato rugose mosaic virus (ToRMV), a new tomato‐infecting begomovirus from Brazil

Abstract

A viral complex causing golden mosaic and leaf distortion (rugosity) in tomato plants was obtained from viruliferous whiteflies, and named TGV-Ub1. This complex was sap-transmitted from tomato to Nicotiana benthamiana . PCR amplification using universal begomovirus primers yielded two distinct fragments for DNA-A, suggesting that the TGV-Ub1 complex comprised at least two distinct viruses. Clones corresponding to full-length viral genomes were obtained from tomato plants infected with TGV-Ub1. Comparisons of the complete sequences of clones pUb1-49 (DNA-A), pUb1-62 and pUb1-81 (both DNA-B) indicated that they constitute novel western hemisphere begomoviruses. Clones pUb1-49 and pUB1-81 have identical common regions, thus representing the cognate DNA-A and -B of a novel begomovirus, named Tomato rugose mosaic virus (ToRMV). Clone pUb1-62 has a distinct common region from ToRMV and all other geminiviruses. A cognate DNA-A for pUb1-62 was not found. Clones containing 1·8 copies of the genomic components were constructed. Infectivity assays of these clones in tomato and N. benthamiana demonstrated that the clones corresponding to ToRMV systemically infected both hosts. Symptoms were analogous to those observed when using the pure isolates obtained in this study. The combination of pUb1-49 and -62 did not result in systemic infection, indicating that these components do not form a viable virus. ToRMV was sap-transmitted from N. benthamiana to N. benthamiana , and by grafting to Solanum tuberosum and Datura stramonium . ToRMV-A and ToRMV-B were detected in plants of Nicandra physaloides and Phaseolus vulgaris , respectively, growing in nearby tomato fields, in association with distinct DNA components.

Characterization of a New World Monopartite Begomovirus Causing Leaf Curl Disease of Tomato in Ecuador and Peru Reveals a New Direction in Geminivirus Evolution

“…Indeed, at least 67 species of tomato-infecting begomoviruses have been described, which is the largest number infecting any crop (5,19). In the OW, monopartite begomoviruses predominate, although there are a few bipartite species, whereas in the NW only bipartite species have been described (1,6,8,(19)(20)(21). However, the finding that DNA-A components of some bipartite tomato-infecting begomoviruses are infectious has blurred the distinction between the monopartite and bipartite genomes.…”

“…The absence of indigenous monopartite begomoviruses in the NW can be explained by the predominance of a bipartite progenitor(s) on the landmasses that gave rise to the NW or a subsequent introduction event. Local evolution events then drove the emergence of new begomovirus species that reflected the genome structure of the virus(es) in a given geographical area, i.e., bipartite species in the NW (1,5,7,20,21,(59)(60)(61) and monopartite (1,48) and, to a lesser extent, bipartite species in the OW (1,11,62). In addition, a few evolutionary events in the OW have involved changes in the viral genome structure, e.g., the aforementioned TYLCTHV, which can exist as a bipartite or monopartite virus, and the monopartite Sri Lankan cassava mosaic virus, which acquired a DNA-B component and became bipartite (9).…”

A review of geminivirus diseases in vegetables and other crops in Brazil: current status and approaches for management

“…To date, at least 14 recognized species of tomato-infecting begomoviruses have been described from Brazil (Ribeiro et al, 2003;Fernandes et al, 2006;Castillo-Urquiza et al, 2008;Barbosa et al, 2011;Albuquerque et al, 2012b;Rocha et al, 2013). The disease symptoms induced by these viruses include stunting and distorted growth and golden-light green-yellow mosaic/ mottle, crumpling, curling, interveinal chlorosis, rugosity, vein yellowing and purpling, and yellow spotting in leaves ( Figures 1B, 2B, 2C).…”

RNA de interferência como estratégia para controle de begomoviroses

“…Esses agentes apresentam alta variabilidade genética e se adaptaram a essa cultura rapidamente via eventos de recombinação (Ribeiro et al, 2003) . De acordo com Brown et al (2015), atualmente existem pelo menos 16 espécies de begomovírus associados a tomateiro no Brasil: Tomato golden mosaic virus (Maytis et al, 1975), Tomato rugose mosaic virus (Fernandes et al, 2006), Tomato chlorotic mottle virus (Ribeiro et al, 2007), Tomato yellow spot virus (Calegario et al, 2007), Tomato severe rugose virus (Fernandes et al, 2008), Os vírus tomato severe rugose virus (ToSRV), tomato golden vein virus (TGVV), tomato common mosaic virus (ToCmMV), tomato chlorotic mottle virus (ToCMoV) e tomato yellow vein streak virus (ToYVSV) são os agentes predominantes nas principais áreas produtoras do país (Fernandes et al, 2008) (Albuquerque et al, 2012) (Barbosa et al, 2015). No entanto, as populações de begomovírus ao longo do tempo demonstram alta…”

“…Uma alíquota do clone infeccioso de ToRMV (DNA-A e DNA-B) (Fernandes et al, 2006), foi gentilmente cedida pelo Dr Murilo Zerbini (BIOAGRO-UFV). A multiplicação desse clone em E. coli foi realizada seguindo os mesmos parâmetros citados para o clone de ToCMoV, descrito anteriormente.…”