Bijaya Sapkota
Engineer
Abstract
Raspberry (Rubus idaeus L.) is susceptible to aphid-borne viruses. We studied the incidence of four of them – black raspberry necrosis virus (BRNV), raspberry leaf mottle virus (RLMV), raspberry vein chlorosis virus (RVCV), and Rubus yellow net virus (RYNV) – in raspberry plants and aphids in and around Norwegian raspberry crops for three years (2019, 2021, and 2022). Most of the samples were from symptomatic plants. Applying RT-PCR, 274 leaf samples and 107 aphid samples were analyzed. All four viruses were found, but BRNV dominated: it was detected in 93% of the 178 leaf samples with virus and was the only virus that occurred more frequently as a single infection than in co-infections with the other viruses. The old cv. Veten had the highest virus incidence (97%) among the sampled plants, followed by uncultivated raspberry in the boundary vegetation (82%). All aphids identified were Amphorophora idaei and Aphis idaei. BRNV and/or RLMV was detected in 27% of the aphid samples. Notably, BRNV was detected in 30% of A. idaei samples, a species not known as a BRNV vector. In subsequent transmission experiments we found that although A. idaei can acquire BRNV within one hour, it did not transmit the virus to healthy raspberry plants. In contrast, Am. idaei, a known BRNV vector, was able to acquire the virus within one minute and transmit it within one hour of inoculation. Our study will improve the identification and management of BRNV.
Authors
Jiunn Luh Tan Nina Trandem Zhibo Hamborg Bijaya Sapkota Dag-Ragnar Blystad Jana Fránová Rostislav ZemekAbstract
No abstract has been registered
Authors
Igor Koloniuk Jana Fránová Jaroslava Pribylová Tatiana Sarkisova Josef Špak Jiunn Luh Tan Rostislav Zemek Radek Cmejla Martina Rejlová Lucie Valentová Jiri Sedlák Jan Holub Jan Skalik Dag-Ragnar Blystad Bijaya Sapkota Zhibo HamborgAbstract
Raspberry plants, valued for their fruits, are vulnerable to a range of viruses that adversely affect their yield and quality. Utilizing high-throughput sequencing (HTS), we identified a novel virus, tentatively named raspberry enamovirus 1 (RaEV1), in three distinct raspberry plants. This study provides a comprehensive characterization of RaEV1, focusing on its genomic structure, phylogeny, and possible transmission routes. Analysis of nearly complete genomes from 14 RaEV1 isolates highlighted regions of variance, particularly marked by indel events. The evidence from phylogenetic and sequence analyses supports the classification of RaEV1 as a distinct species within the Enamovirus genus. Among the 289 plant and 168 invertebrate samples analyzed, RaEV1 was detected in 10.4% and 0.4%, respectively. Most detections occurred in plants that were also infected with other common raspberry viruses. The virus was present in both commercial and wild raspberries, indicating the potential of wild plants to act as viral reservoirs. Experiments involving aphids as potential vectors demonstrated their ability to acquire RaEV1 but not to successfully transmit it to plants.