A novel emaravirus is associated with redbud yellow ringspot disease

Abstract

Yellow ringspot is the only virus-like disease reported in redbud (Cercis spp.) with symptoms including vein clearing, chlorotic ringspots and oak-leaf pattern. A putative new emaravirus was present in all trees displaying typical yellow ringspot symptoms and the name redbud yellow ringspot associated virus is proposed. The virus genome is composed of at least five RNA segments. Two coding regions were studied to determine isolate diversity with results pointing to a homogeneous virus population. Host range was evaluated using graft transmission and by testing species found in close proximity to infected trees. Mite transmission with Aculops cercidis, the predominant species found in redbud trees in the epicenter of the disease, was evaluated but was not found to be a vector of the virus. Based on this study and the accumulated knowledge on emaravirus evolution we propose that speciation is allopatric, with vectors being a major component of the process.

The population structure of Rose rosette virus in the USA

“…Similar findings have also been observed in pigeon pea sterility mosaic virus-2 isolates, with 5 % variability seen in the RNA 5 segment [54]. In addition, diversity in RNA 3 and RNA 4 was similar to that previously observed for RRV and other emaraviruses [55][56][57][58][59][60][61].…”

“…These isolates were collected from different locations. Similar additions and truncations have been reported from several other viruses, but the functions of these truncated proteins remain to be determined [55,63,64]. The role of p6a has not been elucidated, but these features could serve as a way to differentiate RRV isolates.…”

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

“…The present study is based on a collection of 33 isolates from different geographic areas and hosts (wild and cultivated blackberries) in the United States, which thus represent different agroecological conditions. Analysis revealed significant conservation of sequences in the genes studied, similar to reports for other members of the genus; this may possibly be a result of the triple co‐evolution of virus, host and vector (Laney et al ., ; Walia et al ., ; Roßbach et al ., ; Di Bello et al ., ).…”

“…After electrophoresis on an agarose gel, amplicons of the expected size were purified using QIAquick MiniElute Gel Extraction kit (QIAGEN) and directly sequenced in both directions as described by Di Bello et al . (). When ambiguous sites were identified, amplicons were cloned and three clones sequenced.…”

A new, widespread emaravirus discovered in blackberry

“…Six viruses are currently recognized as members of the genus: European mountain ash ringspot-associated virus, fig mosaic virus (FMV), wheat mosaic virus (WMoV), pigeon pea sterility mosaic virus (PPSMV), raspberry leaf blotch virus (RLBV) and rose rosette virus (RRV) (ICTV Master Species List, 2015 v1). Three recently characterized viruses; actinidia chlorotic ringspot-associated virus (AcCRaV), pigeon pea sterility mosaic virus 2 (PPSMV-2) and redbud yellow ringspot-associated virus (RYRSaV) are bona fide members of the genus and await official recognition (Di Bello et al, 2016;Elbeaino et al, 2015;Zheng et al, 201x).…”