A new, widespread emaravirus discovered in blackberry

Abstract

A new virus was identified in blackberry plants exhibiting leaf mottling, chlorotic ringspots and curved midribs, symptoms associated with blackberry yellow vein disease (BYVD). The genome of the new virus, provisionally named blackberry leaf mottle-associated virus (BLMaV), was characterized and phylogenetic analysis revealed its close relationship to recognized members of the genus Emaravirus. BLMaV was transmitted by a yet to be described eriophyid mite species, further reinforcing its placement in the genus. Detection protocols were developed and used to determine the presence of the virus in plants collected from several areas in the U.S.A. The incidence of BLMaV was greater than 40% in BYVD-affected material.

Population structure, evolution and detection of blackberry leaf mottle‐associated virus, an emerging emaravirus

“…The sensitivity of the qPCR assay was compared to the conventional PCR technique described earlier by Hassan et al . (), using the same cDNA templates as in the qPCR assay. The qPCR was found to be at least 1000‐fold more sensitive than conventional PCR.…”

“…The new protocol was compared with the RT‐PCR protocol of Hassan et al . (), using all the isolates sequenced in this study with pairwise comparisons performed as described in Poudel et al . ().…”

“…Blackberry yellow vein, a disease caused by the synergistic effects of several viruses, is the major constraint for blackberry production in the southern United States (Martin & Tzanetakis, ). Recently, a new member of the genus Emaravirus , Blackberry leaf mottle‐associated virus (BLMaV), was detected in a large number of cultivated and wild blackberries affected by yellow vein (Hassan et al ., ).…”

“…Five single‐stranded negative‐sense RNAs (−ssRNA) have been identified as part of the BLMaV genome (Hassan et al ., ). RNA1 encodes the RNA‐dependent RNA polymerase (RdRp) and RNA2 the glycoprotein precursor, processed into two mature glycoproteins.…”

“…RNA3 encodes the nucleocapsid protein (NP; Mielke & Muehlbach, ; Elbeaino et al ., ; McGavin et al ., ) and RNA4 the movement protein (MP; Laney et al ., ; Yu et al ., ). RNA5 codes for a hypothetical protein of unknown function (Hassan et al ., ).…”