Occurrence of a closely-related isolate to Maize yellow striate virus in wheat plants

In Argentina, wheat fields have exhibited virus-like symptoms, such as chlorotic streaking, dwarfing, yellowing and empty ears since 2007. Symptomatic plants and leaves samples were collected in 2007 from Marcos Juarez and in 2008 and 2013 from Río Cuarto. The virus was experimentally transmitted from symptomatic wheat plants to wheat cv. Baguette 10 and cv. BioINTA 3005 using the vector Delphacodes kuscheli Fennah (Delphacidae), producing chlorotic streaking, dwarfing and yellowing in the inoculated cereals at 10?15 days post-inoculation. Virus presence was confirmed by electron microscopy and RT-PCR using degenerated primers, which amplified a conserved region of the plant rhabdovirus polymerase (L) gene. Sequence comparison showed 98% nucleotide identity with Maize yellow striate virus C. Caroya (JQ715419) isolated from corn in Argentina. To our knowledge, this is the first report of the occurrence of Maize yellow striate virus in wheat in Argentina.Fil: Dumón, Analía Delina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mattio, Maria Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Argüello Caro, Evangelina Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Alemandri, Vanina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Puyané, Valeria Aida. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: del Vas, Mariana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: López Lambertini, Paola María. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Truol, Graciela Ana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentin

Identification and biological characterization of Barley yellow striate mosaic virus (BYSMV): a new wheat disease in Argentina

Wheat (Triticum aestivum L.) is the most important winter grain in Argentina. Its production is limited by several factors, including viral diseases. The aim of this study was to identify and characterize a recently detected disease of wheat crops in Argentina. Symptomatic plants were collected from different locations from the wheat production area, Miramar and Balcarce (Buenos Aires), Río Cuarto, Rosales and Marcos Juarez (Córdoba), Paraná (Entre Ríos) and General Pico (La Pampa). Samples were characterized by: electron microscopy (leaf-dip and ultrathin sections), serological tests (with antiserum reacting against different wheat viruses by DAS-ELISA and indirect ELISA), mechanical, seed and vector transmission assays, differential host range, and susceptibility of different wheat cultivars in natural infections. The results showed that this new disease is caused by Barley yellow striate mosaic virus (BYSMV) (Rhabdoviridae-Cytorhabdovirus), a widely distributed virus that can be transmitted to other crops such as barley, oat and triticale. This work representsthe first report of BYSMV in Argentina.El cultivo de trigo (Triticum aestivum L.), es el cereal de invierno de mayor importancia económica en Argentina. Su producción se halla limitada por diversos factores, entre ellos las enfermedades virales. El objetivo del presente trabajo fue identificar y caracterizar biológicamente una enfermedad viral detectada recientemente en el cultivo de trigo en Argentina, que ha presentado elevada incidencia en los últimos años. Para ello, se recolectaron plantas con síntomas en localidades de: Miramar y Balcarce (Buenos Aires), Río Cuarto, Rosales y Marcos Juárez (Córdoba), Paraná (Entre Ríos) y General Pico (La Pampa) de la región triguera Argentina. Las muestras fueron caracterizadas a través de: microscopia electrónica ("leaf-dip" y cortes ultrafinos), serología (con antisueros para diferentes virosis del trigo por DAS-ELISA y ELISA indirecto), transmisión mecánica, por semilla y por vectores (delfácidos), rango de hospedantes diferenciales y susceptibilidad diferencial de diferentes cultivares de trigo en infecciones naturales. Los resultados obtenidos evidenciaron que esta nueva enfermedad es causada por el Barley yellow striate mosaic virus (BYSMV) (Rhabdoviridae-Cytorhabdovirus), un virus ampliamente distribuido a nivel mundial y que representa un riesgo potencial para otros cultivos como cebada, avena y triticale. Este trabajo representa el primer reporte del BYSMV en Argentina.Fil: Dumón, Analía Delina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Unidad de Fitopatología y Modelización Agrícola - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Fitopatología y Modelización Agrícola; ArgentinaFil: Argüello Caro, Evangelina Beatriz. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Alemandri, María V.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Bainotti, Carlos Tomas. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Mattio, María F.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Rodríguez, Sandra M.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: del Vas, Mariana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Truol, Graciela Ana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentin

Effects of Melia azedarach extract on Cotesia ayerza, parasitoid of the alfalfa defoliator Colias lesbia

Extracts from the fruit of Melia azedarach L. (Meliaceae) have shown antifeedant and toxic effects on several insect species, including various pests, but the action of these compounds on natural enemies such as predators and parasitoids is less understood. The purpose of this work was to assess extract effects on Cotesia ayerza (Brèthes) (Hymenoptera: Braconidae), a parasitoid of the alfalfa defoliator Colias lesbia Fab. (Lepidoptera: Pieridae). The extract was first tested on butterfly larvae, in order to determine sublethal concentrations, and thus enable the evaluation of extract effects on parasitoid development from treated hosts. Direct effects of the extract through ingestion or contact (topical application) on adult wasp survival were also evaluated. An extract concentration of 0.2% was selected for parasitoid tests, since it allowed butterfly larvae to survive and pupate at normal rates, while inducing sublethal effects manifested as lower body weight. The indirect effects of the extract, through parasitoid development on treated hosts, were seen only in a female-biased sex ratio, without significant effects on either cocoon formation time, number of cocoons or adult parasitoids emerged. Adult wasps suffered increased mortality when their food was treated with extract, but were unaffected by topical application. These results suggest that M. azedarach extracts could represent an interesting tool for integrated pest management of C. lesbia populations.Fil: Valladares, Graciela Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinario de Biología Vegetal (p); Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Investigaciones Entomológicas de Córdoba; ArgentinaFil: Palacios, Sara Maria. Universidad Católica de Córdoba; ArgentinaFil: Avalos, Delia. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias. Cátedra de Zoología Agrícola; ArgentinaFil: Dumón, Analía Delina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Investigaciones Entomológicas de Córdoba; ArgentinaFil: Defagó, María Teresa. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Investigaciones Entomológicas de Córdoba; Argentin

Wolbachia occurrence in planthopper (Hemiptera: Delphacidae) vectors of cereal viruses in Argentina

Maize (Zea mays L.) and wheat (Triticum aestivum L.) are the most important cereal crops for the Argentinean economy and are affected by several diseases. Different planthopper species transmit causal agents of some of those diseases, including Mal de Río Cuarto virus, barley yellow striate mosaic virus, and the recently proposed maize yellow striate virus. Many planthopper species are sap feeders and therefore are expected to host bacteria providing essential nutrients lacking in the diet. Previous studies have evidenced that some of these bacterial symbionts are involved in the virus transmission. Wolbachia is a group of obligate intracellular bacteria infecting numerous arthropod species and causing reproductive alterations in their hosts. These bacteria have been detected in planthopper species, considered rice pests in various regions of the world. To date, Wolbachia infection status of planthopper species of Argentina is unknown. Amplification by PCR and sequencing of 16S rDNA, wsp- and ftsZ-specific genes demonstrated Wolbachia infection in Caenodelphax teapae (Fowler), Delphacodes kuscheli Fennah, Pyrophagus tigrinus Remes Lenicov & Varela, Tagosodes orizicolus (Muir), and Toya propinqua (Fieber). This is the first report of Wolbachia in delphacid vectors of viruses affecting maize and wheat. An understanding of the bacterial diversity harbored by these insect vectors could lead to new options for future management of diseases of economically important crops in a developing country.Fil: Mattio, Maria Fernanda. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Argüello Caro, Evangelina Beatriz. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rodriguero, Marcela Silvina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Dumón, Analía Delina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Alemandri, V.M.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Truol, Graciela Ana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Co-infection with a wheat rhabdovirus causes a reduction in Mal de Río Cuarto virus titer in its planthopper vector

Mal de Río Cuarto virus (MRCV, Fijivirus, Reoviridae) causes one of the most important diseases in maize (Zea mays L.) in Argentina and has been detected in mixed infections with a rhabdovirus closely related to Maize yellow striate virus. In nature both viruses are able to infect maize and several grasses including wheat, and are transmitted in a persistent propagative manner by Delphacodes kuscheli Fennah (Hemiptera: Delphacidae). This work describes the interactions between MRCV and rhabdovirus within their natural vector and the consequences of such co-infection regarding virus transmission and symptom expression. First- and third-instar D. kuscheli nymphs were fed on MRCV-infected wheat plants or MRCV-rhabdovirus-infected oat plants, and two latency periods were considered. Transmission efficiency and viral load of MRCV-transmitting and non-transmitting planthoppers were determined by real-time quantitative polymerase chain reaction analysis (RTqPCR). Vector transmission efficiency was related to treatments (life stages at acquisition and latency periods). Nevertheless, no correlation between transmission efficiency and type of inoculum used to infect insects with MRCV was found. Treatment by third-instar nymphs 17 days after Acquisition Access Period was the most efficient for MRCV transmission, regardless of the type of inoculum. Plants co-infected with MRCV and rhabdovirus showed the typical MRCV symptoms earlier than plants singly infected with MRCV. The transmitting planthoppers showed significantly higher MRCV titers than non-transmitting insects fed on single or mixed inocula, confirming that successful MRCV transmission is positively associated with viral accumulation in the insect. Furthermore, MRCV viral titers were higher in transmitting planthoppers that acquired this virus from a single inoculum than in those that acquired the virus from a mixed inoculum, indicating that the presence of the rhabdovirus somehow impaired MRCV replication and/or acquisition. This is the first study about interactions between MRCV and a rhabdovirus closely related to Maize yellow striate virus in this insect vector (D. kuscheli), and contributes to a better understanding of planthopper-virus interactions and their epidemiological implications.Fil: Dumón, Analía Delina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Argüello Caro, Evangelina Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Mattio, Maria Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Alemandri, M. V.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: del Vas, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biotecnología y Biología Molecular; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; ArgentinaFil: Truol, Graciela Ana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentin

High viral load in the planthopper vector Delphacodes kuscheli (Hemiptera: Delphacidae) is associated with successful transmission of Mal de Río Cuarto virus

Delphacodes kuscheli Fennah (Hemiptera: Delphacidae) is the main natural vector of Mal de Rio Cuarto virus (family Reoviridae, genus Fijivirus, MRCV), which infects different gramineae and causes the most important maize (Zea mays L.) disease in Argentina. MRCV—vector interactions usually are studied using different winter cereals as hosts. Under experimental conditions, <50% of D. kuscheli planthoppers fed on a MRCV-infected plant can transmit the virus to wheat (Triticum aestivum L. ). This fact is influenced by insect development stage at acquisition and the latency period. This work describes the relation between transmission efficiency and MRCV accumulation in its planthopper vector. First- and third-instar D. kuscheli nymphs were allowed to feed on MRCV-infected plants, and 9 or 17 d after the acquisition access period (AAP), viral load of transmitting and nontransmitting planthoppers was quantified by quantitative polymerase chain reaction. The transmitting planthoppers showed significantly higher viral titers than nontransmitting ones, suggesting that successful transmission is positively associated to viral accumulation in the insect. However, planthoppers of the third-instars group did not transmit the virus 9 d after AAP, even when 46% had similar titers to the transmitting insects of the other treatments. These results indicate that additional factors influence MRCV transmission efficiency when acquisition occurs in older planthoppers. This is the first precise quantitative analysis of MRCV in its main vector species and will definitely contribute to better understand planthopper—Fijivirus interactions and its epidemiological implications.Fil: Argüello Caro, Evangelina Beatriz. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Maroniche, Guillermo Andrés. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Dumón, Analía Delina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sagadín, Mónica B.. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: del Vas, Mariana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Truol, Graciela Ana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Virus transmitidos por el ácaro Aceria tosichella Keifer: Wheat streak mosaic virus (WSMV) y Wheat mosaic virus (WMoV)

En este trabajo se presentan los resultados de una prospección de las virosis transmitidas por el ácaro Aceria tosichella Keifer: Wheat streak mosaic virus (WSMV) y Wheat mosaic virus (WMoV), en las provincias de Córdoba, Buenos Aires y Salta en el período 2011 en cultivos de trigo, y los de su incidencia en la localidad de Balcarce según cultivar y cinco fechas de siembra.Fil: Alemandri, Vanina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Mattio, Maria Fernanda. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Arguello Caro, Evangelina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Dumón, Analía Delina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Abbate, Pablo Eduardo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Pontaroli, Ana. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bainotti, Carlos. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Córdoba. Estación Experimental Agropecuaria Marcos Juarez; ArgentinaFil: Truol, Graciela Ana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentin

Complete genome sequence of maize yellow striate virus, a new cytorhabdovirus infecting maize and wheat crops in Argentina

A rhabdovirus infecting maize and wheat cropsin Argentina was molecularly characterized. Through nextgeneration sequencing (NGS) of symptomatic leaf samples,the complete genome was obtained of two isolates of maizeyellow striate virus (MYSV), a putative new rhabdovirus,differing by only 0.4% at the nucleotide level. The MYSVgenome consists of 12,654 nucleotides for maize and wheatvirus isolates, and shares 71% nucleotide sequence identitywith the complete genome of barley yellow striate mosaicvirus (BYSMV, NC028244). Ten open reading frames(ORFs) were predicted in the MYSV genome from theantigenomic strand and were compared with their BYSMVcounterparts. The highest amino acid sequence identity ofthe MYSV and BYSMV proteins was 80% between the Lproteins, and the lowest was 37% between the proteins 4.Phylogenetic analysis suggested that the MYSV isolatesare new members of the genus Cytorhabdovirus, familyRhabdoviridae. Yellow striate, affecting maize and wheatcrops in Argentina, is an emergent disease that presents apotential economic risk for these widely distributed crops.Fil: Maurino, Maria Fernanda. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Dumón, Analía Delina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Llauger, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Alemandri, Vanina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: de Haro, Luis Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Mattio, Maria Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: del Vas, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Laguna, Irma Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Giménez, María de la Paz. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentin

Mal de Río Cuarto virus infection causes hormone imbalance and sugar accumulation in wheat leaves

Abstract Background Mal de Río Cuarto virus (MRCV) infects several monocotyledonous species including maize and wheat. Infected plants show shortened internodes, partial sterility, increased tillering and reduced root length. To better understand the molecular basis of the plant-virus interactions leading to these symptoms, we combined RNA sequencing with metabolite and hormone measurements. Results More than 3000 differentially accumulated transcripts (DATs) were detected in MRCV-infected wheat plants at 21 days post inoculation compared to mock-inoculated plants. Infected plants exhibited decreased levels of TaSWEET13 transcripts, which are involved in sucrose phloem loading. Soluble sugars, starch, trehalose 6-phosphate (Tre6P), and organic and amino acids were all higher in MRCV-infected plants. In addition, several transcripts related to plant hormone metabolism, transport and signalling were increased upon MRCV infection. Transcripts coding for GA20ox, D14, MAX2 and SMAX1-like proteins involved in gibberellin biosynthesis and strigolactone signalling, were reduced. Transcripts involved in jasmonic acid, ethylene and brassinosteroid biosynthesis, perception and signalling and in auxin transport were also altered. Hormone measurements showed that jasmonic acid, brassinosteroids, abscisic acid and indole-3-acetic acid were significantly higher in infected leaves. Conclusions Our results indicate that MRCV causes a profound hormonal imbalance that, together with alterations in sugar partitioning, could account for the symptoms observed in MRCV-infected plants