Barley Yellow Mosaic Virus Research Articles

Host casein kinase 1-mediated phosphorylation modulates phase separation of a rhabdovirus phosphoprotein and virus infection.

Liquid-liquid phase separation (LLPS) plays important roles in forming cellular membraneless organelles. However, how host factors regulate LLPS of viral proteins during negative-sense RNA (NSR) virus infection is largely unknown. Here, we used barley yellow striate mosaic virus (BYSMV) as a model to demonstrate regulation of host casein kinase 1 (CK1) in phase separation and infection of NSR viruses. We first found that the BYSMV phosphoprotein (P) formed spherical granules with liquid properties and recruited viral nucleotide (N) and polymerase (L) proteins in vivo. Moreover, the P-formed granules were tethered to the ER/actin network for trafficking and fusion. BYSMV P alone formed droplets and incorporated the N protein and the 5' trailer of genomic RNA in vitro. Interestingly, phase separation of BYSMV P was inhibited by host CK1-dependent phosphorylation of an intrinsically disordered P protein region. Genetic assays demonstrated that the unphosphorylated mutant of BYSMV P exhibited condensed phase, which promoted viroplasm formation and virus replication. Whereas, the phosphorylation-mimic mutant existed in diffuse phase state for virus transcription. Collectively, our results demonstrate that host CK1 modulates phase separation of the viral P protein and virus infection.

Developing reverse genetics systems of northern cereal mosaic virus to reveal superinfection exclusion of two cytorhabdoviruses in barley plants.

Recently, reverse genetics systems of plant negative‐stranded RNA (NSR) viruses have been developed to study virus–host interactions. Nonetheless, genetic rescue of plant NSR viruses in both insect vectors and monocot plants is very limited. Northern cereal mosaic virus (NCMV), a plant cytorhabdovirus, causes severe diseases in cereal plants through transmission by the small brown planthopper (SBPH, Laodelphax striatellus) in a propagative manner. In this study, we first developed a minireplicon system of NCMV in Nicotiana benthamiana plants, and then recovered a recombinant NCMV virus (rNCMV‐RFP), with a red fluorescent protein (RFP) insertion, in SBPHs and barley plants. We further used rNCMV‐RFP and green fluorescent protein (GFP)‐tagged barley yellow striate mosaic virus (rBYSMV‐GFP), a closely related cytorhabdovirus, to study superinfection exclusion, a widely observed phenomenon in dicot plants rarely studied in monocot plants. Interestingly, cellular superinfection exclusion of rBYSMV‐GFP and rNCMV‐RFP was observed in barley leaves. Our results demonstrate that two insect‐transmitted cytorhabdoviruses are enemies rather than friends at the cellular level during coinfections in plants.

Barley yellow striate mosaic virus

Barley yellow striate mosaic virus

Survey for Legume and Cereal Viruses in Libya

Abukraa, H., S.G. Kumari and F. Bshia. 2022. Survey for Legume and Cereal Viruses in Libya. Arab Journal of Plant Protection, 40(3): 222-230. https://doi.org/10.22268/AJPP-40.3.222230 A field survey was conducted during March and April 2010, to identify viral diseases affecting cereal and legume crops in different regions of Libya. A total of 3706 barley and wheat samples were collected randomly in addition to 187 symptomatic samples from 22 barley and 20 wheat fields. Moreover, 34 symptomatic legume samples were collected from two faba bean fields and one field each of of lentil, chickpea, Vicia sativa, Vicia ervillia and Vicia narbonesis. All samples were tested at ICARDA Virology Laboratory by tissue blot immunoassay (TBIA) using specific antibodies. Results of random cereal samples showed that Barley yellow dwarf virus-PAV (BYDVPAV) was more common (12.6%) in wheat and barley samples, followed by Wheat dwarf virus (WDV) (1.1%). In symptomatic samples, BYDV-PAV was also the most common (45 out of 187 samples tested were infected: 45/187), followed by WDV (23/187), Barley yellow striate mosaic virus (BYSMV) (40/187) and Maize streak virus (MSV) (7/187). In legume fields, Soybean dwarf virus (SbDV) 13 out of 34 samples tested were infected (13/34) was the most common, followed by Bean leafroll virus (BLRV) (12/34), Chickpea chlorotic stunt virus (CpCSV) (5/34) and Beet western yellows virus (BWYV) (4/34). Serological results were confirmed by amplification with polymerase chain reaction (PCR) using specific primers. This is the first report of WDV, MSV and BYSMV on cereal crops, and BLRV, BWYV, SbDV and CpCSV on legume crops in Libya. Keywords: Libya, Cereals, Legumes, Viruses, TBIA, PCR

A cytorhabdovirus-based expression vector in Nilaparvata lugens, Laodelphax striatellus, and Sogatella furcifera

The brown planthopper (BPH, Nilaparvata lugens), the small brown planthopper (SBPH, Laodelphax striatellus), and the white-backed planthopper (WBPH, Sogatella furcifera) are problematic insect pests and cause severe yield losses through phloem sap-sucking and virus transmission. Barley yellow striate mosaic virus (BYSMV), a plant cytorhabdovirus, has been developed as versatile expression platforms in SBPHs and cereal plants. However, bio-safe overexpression vectors based on recombinant BYSMV (rBYSMV) remain to be developed and applied to the three kinds of planthoppers. Here, we found that rBYSMV was able to infect SBPHs, BPHs and WBPHs through microinjection with crude extracts from rBYSMV-infected barley leaves. To ensure bio-safety of the rBYSMV vectors, we generated an rBYSMV mutant by deleting the accessory protein P3, a putative viral movement protein. As expected, the resulting mutant abolished viral systemic infection in barley plants but had no effects on BYSMV infectivity in insect vectors. Subsequently, we used the modified rBYSMV vector to overexpress iron transport peptide (ITP) in the three kinds of planthoppers and revealed the potential functions of ITP. Overall, our results provide bio-safe overexpression platforms to facilitate functional genomics studies of planthoppers.

A Versatile Expression Platform in Insects and Cereals Based on a Cytorhabdovirus.

In recent years, plant virus-based vectors have been widely applied to express heterologous proteins for genomic studies and commercial production. Among these versatile RNA viral vectors, the barley yellow striate mosaic virus (BYSMV)-based expression vector system has outstanding capability to express large and multiple heterologous proteins. Here we describe a detailed protocol for expression of heterologous proteins using BYSMV expression systems in monocot plants and insects.

A Malting Barley (Hordeum Vulgare L.) Variety, ‘Nurimaeg’ with Resistance to Barley Yellow Mosaic Virus and Tolerance to Lodging Stress

Other SectionsAbstract서 언재료 및 방법결과 및 고찰적 요사 사FigureTableReferenceA malting barley variety, ‘Nurimaeg’, was developed with resistance to barley yellow mosaic virus (BaYMV), tolerance to lodging stress, and good brewing quality. ‘Nurimaeg’ was developed by crossing Milyang127 and Miharu gold in 2004. Regional yield trials were conducted for ‘Nurimaeg’ as a breeding line ‘Iksan175’ in four different regions from 2014-2016. It has a type I growth habit, and its average heading and maturity dates were April 12 and May 20, respectively-which were 1 day later than the maturity date of ‘Hopum’ variety. As ‘Nurimaeg’ has a shorter culm length (77 cm) than that of ‘Hopum’, it showed tolerance to lodging stress. This variety possesses the rym5 gene and is resistant to BaYMV. It showed a 42.9 g 1000-grain weight and 90% assortment ratio. The yield potential of ‘Nurimaeg’ was 408 kg/10a, which is approximately 18% higher than that of ‘Hopum’. Analysis of grain quality for malting showed that ‘Nurimaeg’ has high quality of low protein and β-glucan content. Malt quality analysis revealed that it has 72.8% extract, 4.2% soluble protein, 38.9% kolbach index, and 243 WK diastatic power, which all were similar to those of ‘Hopum’. ‘Nurimaeg’ would be suitable for cultivation in the areas of Korea that have a daily minimum temperature of -4℃ in the month of January (Registration No. 7960).Keywords : malting barley, BaYMV resistance, lodging resistance, malt, variety

Targeted Knockout of Eukaryotic Translation Initiation Factor 4E Confers Bymovirus Resistance in Winter Barley.

The Eukaryotic Translation Initiation Factor 4E (EIF4E) is a well-known susceptibility factor for potyvirus infections in many plant species. The barley yellow mosaic virus disease, caused by the bymoviruses Barley yellow mosaic virus (BaYMV) and Barley mild mosaic virus (BaMMV), can lead to yield losses of up to 50% in winter barley. In autumn, the roots of young barley plants are infected by the soil-borne plasmodiophoraceous parasite Polymyxa graminis L. that serves as viral vector. Upon viral establishment and systemic spreading into the upper parts of the plants, yellow mosaics occur as first symptoms on leaves. In the further course of plant development, the disease entails leaf necrosis and increased susceptibility to frost damage. Thanks to the rym4 and rym5 allelic variants of the HvEIF4E gene, more than two thirds of current European winter barley cultivars are resistant to BaYMV and BaMMV. However, several strains of BaYMV and BaMMV have already overcome rym4- and rym5-mediated resistance. Accordingly, new resistance-conferring alleles are needed for barley breeding. Therefore, we performed targeted mutagenesis of the EIF4E gene by Cas9 endonuclease in BaMMV/BaYMV-susceptible winter barley cv. “Igri”. Small insertions were generated, resulting in a shift of the translational reading frame, thereby causing the loss-of-function of EIF4E. The mutations occurred in the homozygous state already in the primary mutants. Their progeny proved invariably homozygous and fully resistant to mechanical inoculation with BaMMV. EIF4E knockout plants showed normal growth habit and produced grains, yet exhibited a yield penalty.

Identification of novel QTL contributing to barley yellow mosaic resistance in wild barley (Hordeum vulgare spp. spontaneum)

BackgroundBarley yellow mosaic disease (BYMD) caused by Barley yellow mosaic virus (BaYMV) and Barley mild mosaic virus (BaMMV) seriously threatens the production of winter barley. Cultivating and promoting varieties that carry disease-resistant genes is one of the most powerful ways to minimize the disease’s effect on yield. However, as the BYMD virus mutates rapidly, resistance conferred by the two cloned R genes to the virus had been overcome by new virus strains. There is an urgent need for novel resistance genes in barley that convey sustainable resistance to newly emerging virus strains causing BYMD.ResultsA doubled haploid (DH) population derived from a cross of SRY01 (BYMD resistant wild barley) and Gairdner (BYMD susceptible barley cultivar) was used to explore for QTL of resistance to BYMD in barley. A total of six quantitative trait loci (qRYM-1H, qRYM-2Ha, qRYM-2Hb, qRYM-3H, qRYM-5H, and qRYM-7H) related to BYMD resistance were detected, which were located on chromosomes 1H, 2H, 3H, 5H, and 7H. Both qRYM-1H and qRYM-2Ha were detected in all environments. qRYM-1H was found to be overlapped with rym7, a known R gene to the disease, whereas qRYM-2Ha is a novel QTL on chromosome 2H originated from SRY01, explaining phenotypic variation from 9.8 to 17.8%. The closely linked InDel markers for qRYM-2Ha were developed which could be used for marker-assisted selection in barley breeding. qRYM-2Hb and qRYM-3H were stable QTL for specific resistance to Yancheng and Yangzhou virus strains, respectively. qRYM-5H and qRYM-7H identified in Yangzhou were originated from Gairdner.ConclusionsOur work is focusing on a virus disease (barley yellow mosaic) of barley. It is the first report on BYMD-resistant QTL from wild barley accessions. One novel major QTL (qRYM-2Ha) for the resistance was detected. The consistently detected new genes will potentially serve as novel sources for achieving pre-breeding barley materials with resistance to BYMD.

Rapid Visual Detection Method for Barley Yellow Mosaic Virus Using Reverse Transcription Loop-Mediated Isothermal Amplification (RT-LAMP).

Barley yellow mosaic disease, caused mainly by Barley yellow mosaic virus (BaYMV) and Barley mild mosaic virus, is a devastating disease of barley and is a threat to Eurasian barley production. Early detection is essential for effective management of the pathogens and to assure food security. In this study, a simple, rapid, specific, sensitive, and visual method was developed to detect BaYMV using loop-mediated isothermal amplification (LAMP). Two pairs of oligonucleotide primers (inner and outer primers) were designed to amplify the gene encoding the coat protein of BaYMV. The optimal conditions for the LAMP method were determined, and a one-step reverse transcription (RT)-LAMP method was also developed. Subsequently, the fastest processing time for RT-LAMP was determined. Among eight plant viruses examined using the LAMP method, only BaYMV was detectable, suggesting that the assay was highly specific. The RT-LAMP method was 10 times more sensitive than the RT-PCR method in the sensitivity test. To further shorten the virus detection process, a dye was added to the RT-LAMP products, and positive reactions were simply read by the naked eye via a color change (from orange to light green) under visible light. Barley samples from the middle and lower reaches of the Yangtze River basin, where BaYMV broke out very seriously in 1970s, were detected by the newly established RT-LAMP method. The results showed that all samples were positive for BaYMV, indicating the potential risk of the virus in these areas. This newly established LAMP/RT-LAMP method could be a promising tool for barley protection and food security control.

Molecular and functional characterization of the barley yellow striate mosaic virus genes encoding phosphoprotein, P3, P6 and P9

Molecular and functional characterization of the barley yellow striate mosaic virus genes encoding phosphoprotein, P3, P6 and P9

Genomic prediction models trained with historical records enable populating the German ex situ genebank bio-digital resource center of barley (Hordeum sp.) with information on resistances to soilborne barley mosaic viruses

Key messageGenomic prediction with special weight of major genes is a valuable tool to populate bio-digital resource centers.Phenotypic information of crop genetic resources is a prerequisite for an informed selection that aims to broaden the genetic base of the elite breeding pools. We investigated the potential of genomic prediction based on historical screening data of plant responses against the Barley yellow mosaic viruses for populating the bio-digital resource center of barley. Our study includes dense marker data for 3838 accessions of winter barley, and historical screening data of 1751 accessions for Barley yellow mosaic virus (BaYMV) and of 1771 accessions for Barley mild mosaic virus (BaMMV). Linear mixed models were fitted by considering combinations for the effects of genotypes, years, and locations. The best linear unbiased estimations displayed a broad spectrum of plant responses against BaYMV and BaMMV. Prediction abilities, computed as correlations between predictions and observed phenotypes of accessions, were low for the marker-assisted selection approach amounting to 0.42. In contrast, prediction abilities of genomic best linear unbiased predictions were high, with values of 0.62 for BaYMV and 0.64 for BaMMV. Prediction abilities of genomic prediction were improved by up to ~ 5% using W-BLUP, in which more weight is given to markers with significant major effects found by association mapping. Our results outline the utility of historical screening data and W-BLUP model to predict the performance of the non-phenotyped individuals in genebank collections. The presented strategy can be considered as part of the different approaches used in genebank genomics to valorize genetic resources for their usage in disease resistance breeding and research.

Utility of a GFP-expressing Barley yellow mosaic virus for analyzing disease resistance genes.

The soil-borne plasmodiophorid Polymyxa graminis is a vector for Barley yellow mosaic virus (BaYMV), which can severely damage barley plants. Although 22 disease resistance genes have been identified, only a few have been used for breeding virus-resistant cultivars. Recently, BaYMV strains capable of overcoming the effects of some of these genes have been detected. In this study, green fluorescent protein (GFP)-expressing BaYMV was constructed and used to examine viral dynamics in inoculated barley plants. Leaf inoculations resulted in higher infection rates than root or crown inoculations. Additionally, inoculations of some resistant cultivars produced infections that were similar to those observed in a field test. The results of this study indicate that the GFP-expressing virus is a useful tool for visualizing virus replication and dynamics, and for understanding resistance mechanisms.

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Barley plants inoculated with GFP-expressing Barley yellow mosaic virus (BaYMV) to visualize virus replication and dynamics for understanding resistance mechanisms. GFP fluorescence of the susceptible cultivar ‘New Golden’ at 6 weeks post-inoculation of BaYMV pathotype V. Images are of leaves (upper) and roots (bottom) under white light (left) and UV light using a long-pass filter (right). Under UV light, GFP fluorescence was detected in the upper leaves and lateral roots (This issue, p. 484–490).

High-resolution mapping of Rym14Hb, a wild relative resistance gene to barley yellow mosaic disease

Key messageWe mapped the Rym14Hb resistance locus to barley yellow mosaic disease in a 2Mbp interval. The co-segregating markers will be instrumental for marker-assisted selection in barley breeding.Barley yellow mosaic disease is caused by Barley yellow mosaic virus and Barley mild mosaic virus and leads to severe yield losses in barley (Hordeum vulgare) in Central Europe and East-Asia. Several resistance loci are used in barley breeding. However, cases of resistance-breaking viral strains are known, raising concerns about the durability of those genes. Rym14Hb is a dominant major resistance gene on chromosome 6HS, originating from barley’s secondary genepool wild relative Hordeum bulbosum. As such, the resistance mechanism may represent a case of non-host resistance, which could enhance its durability. A susceptible barley variety and a resistant H. bulbosum introgression line were crossed to produce a large F2 mapping population (n = 7500), to compensate for a ten-fold reduction in recombination rate compared to intraspecific barley crosses. After high-throughput genotyping, the Rym14Hb locus was assigned to a 2Mbp telomeric interval on chromosome 6HS. The co-segregating markers developed in this study can be used for marker-assisted introgression of this locus into barley elite germplasm with a minimum of linkage drag.

Molecular characterization of a novel cytorhabdovirus associated with paper mulberry mosaic disease.

A novel cytorhabdovirus, tentatively named "paper mulberry mosaic-associated virus" (PMuMaV), was discovered and identified by transcriptome sequencing (RNA-seq), small RNA sequencing (sRNA-seq), and RT-PCR amplification. The whole-genome sequence of PMuMaV is 13,736 nucleotides (nt) in length and contains six open reading frames (ORFs) encoding a nucleocapsid protein (N), a phosphoprotein (P), a putative movement protein (P3), a matrix protein (M), a glycoprotein (G), and an RNA-dependent RNA polymerase (L). The coding sequences are flanked by a 194-nt leader and a 370-nt trailer sequence at the 3' terminus and 5' terminus, respectively. Pairwise sequence comparisons showed that PMuMaV is related to northern cereal mosaic virus (NCMV, 38.97%), barley yellow striate mosaic virus (BYSMV, 38.86%), and maize yellow striate virus (MYSV, 38.76%), and phylogenetic analysis also placed these viruses together into the same branch, thus suggesting that PMuMaV is a member of a new species in the genus Cytorhabdovirus.

Millet Could Be both a Weed and Serve as a Virus Reservoir in Crop Fields.

Millet is a dangerous weed in crop fields. A lack of seed dormancy helps it to spread easily and be present in maize, wheat, and other crop fields. Our previous report revealed the possibility that millet can also play a role as a virus reservoir. In that study, we focused on visual symptoms and detected the presence of several viruses in millet using serological methods, which can only detect the presence of the investigated pathogen. In this current work, we used small RNA high-throughput sequencing as an unbiased virus diagnostic method to uncover presenting viruses in randomly sampled millet grown as a volunteer weed in two maize fields, showing stunting, chlorosis, and striped leaves. Our results confirmed the widespread presence of wheat streak mosaic virus at both locations. Moreover, barley yellow striate mosaic virus and barley virus G, neither of which had been previously described in Hungary, were also identified. As these viruses can cause severe diseases in wheat and other cereals, their presence in a weed implies a potential infection risk. Our study indicates that the presence of millet in fields requires special control to prevent the emergence of new viral diseases in crop fields.

Advances in reverse genetics system of plant negative-strand RNA viruses

Negative-strand RNA (NSR) viruses contain not only medical important animal pathogens but also agricultural important plant pathogens. These NSR viruses cause deadliest diseases in humans, livestocks and agronomic crops and pose great threat to the health of human being and food security worldwide. The virus reverse genetics system is an important molecular genetic technology to study viral gene functions in virus infection cycle, disease pathology and virus-host interactions. For animal-infecting NSR viruses, the reverse genetics system has been established for more than twenty years. In contrast to the well-established reverse genetics systems for animal-infecting NSR viruses, establishment of such system for the plant-infecting NSR viruses turned out to be an extremely challenge work. Many research groups throughout the world have tried to use the similar strategies used for animal NSR viruses to establish reverse genetics systems for plant-infecting NSR viruses in the last twenty years but none of groups have succeeded. The absence of the reverse genetics system posed a major obstacle to molecular genetic manipulation and subsequent investigation of gene function and disease pathology for plant-infecting NSR viruses. Recently, big breakthroughs have been made in the establishment of the reverse genetics systems for plant NSR viruses by scientists from China and America, respectively. The systems were recently established for both nonsegmented and segmented plant NSR viruses. The reverse genetics system for a nonsegmented plant NSR virus was firstly developed for sonchus yellow net virus (SYNV), a non segmented nucleorhabdovirus NSR. Using the similar strategies as SYNV, barley yellow striate mosaic virus (BYSMV), a nonsegmented cytorhabdovirus NSR, was then succeeded in the establishment of reverse genetics system. The first reverse genetics system for a segmented plant NSR virus was developed using tomato spotted wilt virus (TSWV), a tospovirus with tripartite negative-stranded/ambisense RNA genomes. The reverse genetics system was also recently developed for rose rosette virus (RRV), an emaravirus with seven negative-sense mono-cistronic RNA genomes. The establishment of the reverse genetics system for plant NSR viruses typically involves two steps. The first step requires the construction of a mini-genome replication system. The viral genomic or antigenomic RNA was flanked by hammerhead and ribozyme to generate exact viral 5 ¢ and 3 ¢ end, and driven by 35S promoter. The mini-replicon construct was co-expressed with the constructs expressing nucleocapsid (N) protein, phosphoprotein (P; essential for rhabdovirus) and viral RNA-dependent RNA polymerase (RdRp). For the segmented plant NSR viruses such as TSWV, codon optimization and removal of intron-splicing sites of RdRp sequence are critical for the expression of a functional RdRp from 35S-driven constructs in planta . The second step involves the rescue of virus entirely from full-length infectious cDNA clones in plant. The recombinant virus can carry green fluorescence protein (GFP) gene reporter and infect Nicotiana benthamiana plant systemically. The establishment of reverse genetics for different plant-infecting NSR viruses now provided powerful systems to investigate all aspects of virus infection cycle and disease pathology. The recent breakthroughs of reverse genetics systems have opened a new era for the investigation of plant-infecting NSR viruses in the future.

Casein Kinase 1 Regulates Cytorhabdovirus Replication and Transcription by Phosphorylating a Phosphoprotein Serine-Rich Motif.

Casein kinase 1 (CK1) family members are conserved Ser/Thr protein kinases that regulate important developmental processes in all eukaryotic organisms. However, the functions of CK1 in plant immunity remain largely unknown. Barley yellow striate mosaic virus (BYSMV), a plant cytorhabdovirus, infects cereal crops and is obligately transmitted by the small brown planthopper (SBPH; Laodelphax striatellus). The BYSMV phosphoprotein (P) exists as two forms with different mobilities corresponding to 42 kD (P42) and 44 kD (P44) in SDS-PAGE gels. Mass spectrometric analyses revealed a highly phosphorylated serine-rich (SR) motif at the C-terminal intrinsically disordered region of the P protein. The Ala-substitution mutant (PS5A) in the SR motif stimulated virus replication, whereas the phosphorylation-mimic mutant (PS5D) facilitated virus transcription. Furthermore, PS5A and PS5D associated preferentially with nucleocapsid protein-RNA templates and the large polymerase protein to provide optimal replication and transcription complexes, respectively. Biochemistry assays demonstrated that plant and insect CK1 protein kinases could phosphorylate the SR motif and induce conformational changes from P42 to P44. Moreover, overexpression of CK1 or a dominant-negative mutant impaired the balance between P42 and P44, thereby compromising virus infections. Our results demonstrate that BYSMV recruits the conserved CK1 kinases to achieve its cross-kingdom infection in host plants and insect vectors.

Wheat Argonaute 5 Functions in Aphid-Plant Interaction.

Aphids feeding on plants experience similar responses to pathogens due to the prolonged and intimate contact with the plant. Diuraphis noxia is an economically important aphid pest on wheat that exhibits such an interaction. Studies on small RNA (sRNA) that regulate genes imparting resistance to wheat against D. noxia have predicted an Argonaute 5 (TaAGO5) gene as possible role player in the resistance response. Functional characterization revealed that TaAGO5 is crucial in regulating the response to infestation by D. noxia. Knockdown of TaAGO5 by 22% in D. noxia resistant wheat resulted in a completely susceptible phenotype. The fecundity and stress levels of D. noxia feeding on these silenced plants were similar to aphids feeding on the susceptible controls. Thus, TaAGO5 is crucial in the defense response by wheat plants during aphid feeding and this is similar to Nicotiana benthaminia plants experiencing arthropod herbivory. Additionally, TaAGO5 was differentially regulated by the Barley mosaic virus (BMV) used in the functional characterization. This provides evidence that TaAGO5 could play a role during virus infection of wheat. The role of AGO5 proteins in plant responses to arthropod herbivory and virus infection is known for dicotyledonous plants. Here, we present data that indicate that this role of TaAGO5 is conserved in wheat and possibly for monocotyledonous plants. These observations extend our knowledge on the roles of AGO proteins in plant resistance.