RESUMO
Curly top disease, caused by beet curly top virus (BCTV), is among the most serious viral diseases affecting sugar beets in western USA. The virus is exclusively transmitted by the beet leafhopper (BLH, Circulifer tenellus) in a circulative and non-propagative manner. Despite the growing knowledge on virus-vector interactions, our understanding of the molecular interactions between BCTV and BLH is hampered by limited information regarding the virus impact on the vector and the lack of genomic and transcriptomic resources for BLH. This study unveils the significant impact of BCTV on both the performance and transcriptome response of BLHs. Viruliferous BLHs had higher fecundity than non-viruliferous counterparts, which was evident by upregulation of differentially expressed transcripts (DETs) associated with development, viability and fertility of germline and embryos in viruliferous insects. Conversely, most DETs associated with muscle movement and locomotor activities were downregulated in viruliferous insects, implying potential behavioural modifications by BCTV. Additionally, a great proportion of DETs related to innate immunity and detoxification were upregulated in viruliferous insects. Viral infection also induced notable alterations in primary metabolisms, including energy metabolism, namely glucosidases, lipid digestion and transport, and protein degradation, along with other cellular functions, particularly in chromatin remodelling and DNA repair. This study represents the first comprehensive transcriptome analysis for BLH. The presented findings provide new insights into the multifaceted effects of viral infection on various biological processes in BLH, offering a foundation for future investigations into the complex virus-vector relationship and potential management strategies for curly top disease.
Assuntos
Beta vulgaris , Perfilação da Expressão Gênica , Hemípteros , Insetos Vetores , Doenças das Plantas , Animais , Hemípteros/virologia , Hemípteros/genética , Doenças das Plantas/virologia , Doenças das Plantas/genética , Insetos Vetores/virologia , Insetos Vetores/genética , Beta vulgaris/virologia , Transcriptoma , Geminiviridae/genética , Geminiviridae/fisiologia , Fertilidade/genéticaRESUMO
Disease resistance gene (R gene)-encoded nucleotide-binding leucine-rich repeat proteins (NLRs) are critical players in plant host defence mechanisms because of their role as receptors that recognise pathogen effectors and trigger plant effector-triggered immunity (ETI). This study aimed to determine the putative role of a cassava coiled-coil (CC)-NLR (CNL) gene MeRPPL1 (Manes.12G091600) (single allele) located on chromosome 12 in the tolerance or susceptibility to South African cassava mosaic virus (SACMV), one of the causal agents of cassava mosaic disease (CMD). A transient protoplast system was used to knock down the expression of MeRPPL1 by clustered regularly interspaced short palindromic repeats-CRISPR-associated protein 9 (CRISPR-Cas9). The MeRPPL1-targeting CRISPR vectors and/or SACMV DNA A and DNA B infectious clones were used to transfect protoplasts isolated from leaf mesophyll cells from the SACMV-tolerant cassava (Manihot esculenta) cultivar TME3. The CRISPR/Cas9 silencing vector significantly reduced MeRPPL1 expression in protoplasts whether with or without SACMV co-infection. Notably, SACMV DNA A replication was higher in protoplasts with lower MeRPPL1 expression levels than in non-silenced protoplasts. Mutagenesis studies revealed that protoplast co-transfection with CRISPR-MeRPPL1 silencing vector + SACMV and transfection with only SACMV induced nucleotide substitution mutations that led to altered amino acids in the highly conserved MHD motif of the MeRPPL1-translated polypeptide. This may abolish or alter the regulatory role of the MHD motif in controlling R protein activity and could contribute to the increase in SACMV-DNA A accumulation observed in MeRPPL1-silenced protoplasts. The results herein demonstrate for the first time a role for a CNL gene in tolerance to a geminivirus in TME3.
Assuntos
Begomovirus , Manihot , Doenças das Plantas , Proteínas de Plantas , Replicação Viral , Manihot/virologia , Manihot/genética , Doenças das Plantas/virologia , Doenças das Plantas/genética , Begomovirus/genética , Begomovirus/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Geminiviridae/genética , Geminiviridae/fisiologia , Sistemas CRISPR-Cas , Resistência à Doença/genética , Protoplastos/virologia , Protoplastos/metabolismo , Proteínas de Repetições Ricas em LeucinaRESUMO
The Pepper huasteco yellow vein virus (PHYVV) is an endemic geminivirus in Mexico causing partial or total losses in the pepper crop since the damage caused by the virus has not been fully controlled. In this work, we evaluated the effect of ZnO NPs (0, 50, 100, 150, and 200 mM) as a preventive (72 h before) and curative (72 h after) treatment of PHYVV infection in two jalapeño pepper varieties. In this study, we observed a decrease in symptoms, and it could be caused by an induction of the defense system in pepper plants and a direct action on PHYVV by foliar application of ZnO NPs. Our findings suggest that ZnO NP application significantly decreased the viral titer for both varieties at 200 mM by 15.11-fold. However, this effect was different depending on the timing of application and the variety of pepper. The greatest decrease in the viral titer in the preventive treatment in both varieties was at the concentration of 200 mM (1781.17 and 274.5 times, respectively). For curative treatment in cv. Don Pancho at the concentration of 200 mM (333.33 times) and cv. Don Benito at 100 mM (43.10 folds). compared to control. Furthermore, virus mobility was generally restricted for both varieties at 100 mM (15.13-fold) compared to the control. The results possibly delineated that ZnO NPs increased plant resistance possibly by increasing POD (2.08 and 0.25 times) and SOD (0.998 and 1.38) in cv. Don Pancho and cv. Don Benito, respectively. On the other hand, in cv. Don Pancho and cv. Don Benito presented a decrease in CAT (0.61 and 0.058) and PAL (0.78 and 0.77), respectively. Taken together, we provide the first evidence to demonstrate the effect of ZnO NPs on viral symptoms depending on the plan-virus-ZnO NP interaction.
Assuntos
Begomovirus , Capsicum , Geminiviridae , Óxido de Zinco , Óxido de Zinco/farmacologia , Geminiviridae/fisiologia , PlantasRESUMO
BACKGROUND: Grapevine red blotch virus (GRBV) is the causal agent of grapevine red blotch disease and is known to delay grape ripening. However, grape cell-wall modifications during GRBV infection are largely unknown, even though the cell wall plays a large role in pathogenicity, viral interactions with host plants, and phenolic extractability during winemaking. Understanding the impact of GRBV infection on cell-wall metabolism is important for the development of potential mitigations strategies. In this study, high-throughput transcriptome sequencing was conducted on Vitis vinifera L. 'Merlot' grapes during ripening. The cell-wall composition, phenolic content, and phenolic extractability at two different commercial harvest points were also determined. RESULTS: Log fold changes indicated a strong induction in diseased grapes at harvest of several transcripts involved in cell-wall solubilization and degradation. However, these observations did not translate to changes in cell-wall composition at either harvest point in diseased grapes, potentially suggesting post-transcriptional regulation. Moderate induction of pectin methylesterase inhibitor transcripts and transcripts associated with pathogenesis-related proteins coincided with increases in pectin and soluble proteins in cell walls of diseased grapes at harvest. Both pectin and pathogenesis-related proteins are known to retain phenolic compounds during winemaking. CONCLUSION: Our study corroborates this finding when the percentage extractability of flavonols in wines was significantly lower when made from GRBV-infected fruit. These results suggest GRBV alters the grape cell walls, consequently decreasing phenolic extraction during winemaking. © 2023 Society of Chemical Industry.
Assuntos
Geminiviridae , Vitis , Vinho , Vitis/química , Doenças das Plantas , Vinho/análise , Parede Celular/química , Frutas/química , Fenóis/análise , Geminiviridae/fisiologia , Pectinas/análiseRESUMO
Geminiviruses consist of a single-stranded DNA genome that replicates by a rolling circle (RCR) and recombination-dependent (RDR) modes of replication. The AC1 or Rep is the indispensable viral protein required for the RCR mode of replication. Since these viruses encode only a few proteins, they depend on several host factors for replication, transcription, and other physiological processes. To get insights into the repertoire of host factors influencing the replication of geminiviruses, we performed phage display experiments which led to the identification of putative mungbean yellow mosaic India virus (MYMIV) Rep interacting host proteins. These proteins might directly or indirectly participate in geminivirus biology. MCM3 was one of the Rep-interacting partners obtained in the phage display results. Using bimolecular fluorescence complementation (BiFC), the interaction of the MYMIV Rep with Arabidopsis thaliana MCM3 (AtMCM3) was confirmed. We report the involvement of AtMCM3 in the replication of MYMIV DNA through an ex vivo system. The physiological relevance of the interaction between AtMCM3 and MYMIV Rep is reflected by yeast replication assay.Communicated by Ramaswamy H. Sarma.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Geminiviridae , Componente 3 do Complexo de Manutenção de Minicromossomo , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/virologia , DNA Helicases/genética , DNA Helicases/metabolismo , Replicação do DNA , DNA Viral/genética , DNA Viral/metabolismo , Geminiviridae/fisiologia , Componente 3 do Complexo de Manutenção de Minicromossomo/genética , Componente 3 do Complexo de Manutenção de Minicromossomo/metabolismo , Replicação Viral , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismoRESUMO
The family Geminiviridae includes viruses with mono- or bipartite single-stranded, circular DNA genomes of 2.5-5.2 kb. They cause economically important diseases in most tropical and subtropical regions of the world. Geminiviruses infect dicot and monocot plants and are transmitted by insect vectors. DNA satellites are associated with some geminiviruses. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Geminiviridae which is available at ictv.global/report/geminiviridae.
Assuntos
Geminiviridae/classificação , Doenças das Plantas/virologia , Animais , DNA de Cadeia Simples/química , DNA de Cadeia Simples/genética , DNA Viral/química , DNA Viral/genética , Geminiviridae/genética , Geminiviridae/fisiologia , Geminiviridae/ultraestrutura , Ordem dos Genes , Insetos/virologia , Vírion/química , Vírion/genética , Vírion/ultraestrutura , Replicação ViralRESUMO
The fast-paced evolution of viruses enables them to quickly adapt to the organisms they infect by constantly exploring the potential functional landscape of the proteins encoded in their genomes. Geminiviruses, DNA viruses infecting plants and causing devastating crop diseases worldwide, produce a limited number of multifunctional proteins that mediate the manipulation of the cellular environment to the virus' advantage. Among the proteins produced by the members of this family, C4, the smallest one described to date, is emerging as a powerful viral effector with unexpected versatility. C4 is the only geminiviral protein consistently subjected to positive selection and displays a number of dynamic subcellular localizations, interacting partners, and functions, which can vary between viral species. In this review, we aim to summarize our current knowledge on this remarkable viral protein, encompassing the different aspects of its multilayered diversity, and discuss what it can teach us about geminivirus evolution, invasion requirements, and virulence strategies.
Assuntos
Geminiviridae/fisiologia , Geminiviridae/patogenicidade , Proteínas Virais/metabolismo , Evolução Molecular , Doenças das Plantas/genética , VirulênciaRESUMO
Alfalfa leaf curl virus (ALCV) is the first geminivirus for which aphid transmission was reported. Transmission by Aphis craccivora was determined previously to be highly specific and circulative. Using various complementary techniques, the transmission journey of ALCV was monitored from its uptake from infected plant tissues up to the head of its vector. ALCV was shown to be restricted to phloem tissues using fluorescence in situ hybridization (FISH) and electropenetrography (EPG) monitoring of virus acquisition. Furthermore, the virus is heterogeneously distributed in phloem tissues, as revealed by FISH and quantitative PCR of viral DNA acquired by EPG-monitored aphids. Despite the efficient ingestion of viral DNA, about 106 viral DNA copies per insect in a 15 h feeding period on ALCV-infected plants, the individual maximum transmission rate was 12â%. Transmission success was related to a critical viral accumulation, around 1.6×107 viral DNA copies per insect, a threshold that generally needed more than 48 h to be reached. Moreover, whereas the amount of acquired virus did not decrease over time in the whole aphid body, it declined in the haemolymph and heads. ALCV was not detected in progenies of viruliferous aphids and did not affect aphid fitness. Compared to geminiviruses transmitted by whiteflies or leafhoppers, or to luteoviruses transmitted by aphids, the transmission efficiency of ALCV by A. craccivora is low. This result is discussed in relation to the aphid vector of this geminivirus and the agroecological features of alfalfa, a hardy perennial host plant.
Assuntos
Afídeos/virologia , Geminiviridae/fisiologia , Insetos Vetores/virologia , Medicago sativa/virologia , Doenças das Plantas/virologia , Animais , Afídeos/fisiologia , DNA Viral/genética , Geminiviridae/classificação , Geminiviridae/genética , Hibridização in Situ FluorescenteRESUMO
Geminiviruses are a family of single-stranded DNA viruses that infect many plant species and cause serious diseases in important crops. The plant protein kinase, SnRK1, has been implicated in host defenses against geminiviruses. Overexpression of SnRK1 makes plants more resistant to geminivirus infection, and knock-down of SnRK1 increases susceptibility to geminivirus infection. GRIK, the SnRK1 activating kinase, is upregulated by geminivirus infection, while the viral C2 protein inhibits the SnRK1 activity. SnRK1 also directly phosphorylates geminivirus proteins to reduce infection. These data suggest that SnRK1 is involved in the co-evolution of plant hosts and geminiviruses.
Assuntos
Geminiviridae/fisiologia , Doenças das Plantas/virologia , Proteínas de Plantas/metabolismo , Proteínas Quinases/metabolismo , Resistência à Doença , Geminiviridae/genética , Geminiviridae/metabolismo , Interações Hospedeiro-Patógeno , Fosforilação , Proteínas de Plantas/genética , Proteínas Quinases/genética , Proteínas Virais/genética , Proteínas Virais/metabolismoRESUMO
Geminiviruses possess single-stranded, circular DNA genomes and control the transcription of their late genes, including BV1 of many bipartite begomoviruses, through transcriptional activation by the early expressing AC2 protein. DNA binding by AC2 is not sequence-specific; hence, the specificity of AC2 activation is thought to be conferred by plant transcription factors (TFs) recruited by AC2 in infected cells. However, the exact TFs AC2 recruits are not known for most viruses. Here, we report a systematic examination of the BV1 promoter (PBV1) of the mungbean yellow mosaic virus (MYMV) for conserved promoter motifs. We found that MYMV PBV1 contains three abscisic acid (ABA)-responsive elements (ABREs) within its first 70 nucleotides. Deleting these ABREs, or mutating them all via site-directed mutagenesis, abolished the capacity of PBV1 to respond to AC2-mediated transcriptional activation. Furthermore, ABRE and other related ABA-responsive elements were prevalent in more than a dozen Old World begomoviruses we inspected. Together, these findings suggest that ABA-responsive TFs may be recruited by AC2 to BV1 promoters of these viruses to confer specificity to AC2 activation. These observations are expected to guide the search for the actual TF(s), furthering our understanding of the mechanisms of AC2 action.
Assuntos
Ácido Abscísico/farmacologia , Proteínas de Ligação a DNA/metabolismo , Geminiviridae/fisiologia , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Doenças das Plantas/virologia , Regiões Promotoras Genéticas , Proteínas Virais/genética , Proteínas Virais/metabolismo , Sequência de Bases , Expressão Gênica , Genes Reporter , Vetores Genéticos/genética , Elementos de RespostaRESUMO
Geminivirus particles, consisting of a pair of twinned isometric structures, have one of the most distinctive capsids in the virological world. Until recently, there was little information as to how these structures are generated. To address this, we developed a system to produce capsid structures following the delivery of geminivirus coat protein and replicating circular single-stranded DNA (cssDNA) by the infiltration of gene constructs into plant leaves. The transencapsidation of cssDNA of the Begomovirus genus by coat protein of different geminivirus genera was shown to occur with full-length but not half-length molecules. Double capsid structures, distinct from geminate capsid structures, were also generated in this expression system. By increasing the length of the encapsidated cssDNA, triple geminate capsid structures, consisting of straight, bent and condensed forms were generated. The straight geminate triple structures generated were similar in morphology to those recorded for a potato-infecting virus from Peru. These finding demonstrate that the length of encapsidated DNA controls both the size and stability of geminivirus particles.
Assuntos
Proteínas do Capsídeo/genética , Capsídeo/química , DNA de Cadeia Simples/química , DNA Viral/química , Geminiviridae/fisiologia , Folhas de Planta/virologia , Empacotamento do Genoma Viral , Sequência de Aminoácidos , Geminiviridae/genética , Solanum tuberosum/virologiaRESUMO
Geminiviruses (viruses with circular, single-stranded DNA genomes) are one of the major groups of plant viruses causing severe economic problems for agriculture worldwide. The control of these pathogens has become a priority to maintain the production of important crops, including cotton, maize, cassava, and other vegetables. Obtaining resistant plants is the most powerful strategy and a key factor to stablish an effective integrated pest management for a robust control. In the last few decades, numerous studies have successfully approached that goal using diverse strategies based on plant variability or on the engineered expression of proteins/RNAs. The increasing knowledge of the mechanisms involved in the geminivirus-plant-vector interactions, in combination with the development of gene editing technology and nanoparticles, draw new and promising strategies for a durable control of these emerging pathogens.
Assuntos
Produtos Agrícolas/genética , Geminiviridae/fisiologia , Edição de Genes/tendências , Nanotecnologia/tendências , Doenças das Plantas/imunologia , Doenças das Plantas/virologia , Plantas Geneticamente Modificadas/genética , Produtos Agrícolas/imunologia , Produtos Agrícolas/virologia , Geminiviridae/genética , Geminiviridae/imunologia , Edição de Genes/métodos , Nanotecnologia/métodos , Doenças das Plantas/genética , Imunidade Vegetal , Plantas Geneticamente Modificadas/imunologia , Plantas Geneticamente Modificadas/virologiaRESUMO
Two members of the genus Capulavirus (Geminiviridae) are transmitted by aphids including Alfalfa leaf curl virus (ALCV) transmitted by Aphis craccivora. The capulavirus Euphorbia caput-medusae latent virus was shown here to be transmitted also by A. craccivora, using the population EuphorbiaSA. ALCV was transmissible by several A. craccivora populations including Robinia, but not the EuphorbiaSA population, reflecting a high transmission specificity. Typical of the circulative-persistent mode of transmission, ALCV persists through insect molts. ALCV accumulation and localization were analyzed in whole insects, midguts, hemolymphs, and heads of aphids from vector and non-vector populations of A. craccivora and from the non-vector species Acyrthosiphon pisum. Vector and non-vector populations could be distinguished by contrasted virus accumulations and midgut intracellular localization consistent with a gut barrier to the transmission of ALCV in A. pisum and a primary salivary gland barrier in A. craccivora.
Assuntos
Afídeos/virologia , Geminiviridae/fisiologia , Insetos Vetores/virologia , Medicago sativa/virologia , Doenças das Plantas/virologia , Animais , Afídeos/fisiologia , Geminiviridae/classificação , Geminiviridae/genética , Geminiviridae/isolamento & purificação , Insetos Vetores/fisiologia , Filogenia , Especificidade da EspécieRESUMO
Single-stranded DNA (ssDNA) plant viruses belong to the families Geminiviridae and Nanoviridae. They are transmitted by Hemipteran insects in a circulative, mostly non-propagative, manner. While geminiviruses are transmitted by leafhoppers, treehoppers, whiteflies and aphids, nanoviruses are transmitted exclusively by aphids. Circulative transmission involves complex virus-vector interactions in which epithelial cells have to be crossed and defense mechanisms counteracted. Vector taxa are considered a relevant taxonomic criterion for virus classification, indicating that viruses can evolve specific interactions with their vectors. Thus, we predicted that, although nanoviruses and geminiviruses represent related viral families, they have evolved distinct interactions with their vector. This prediction is also supported by the non-structural Nuclear Shuttle Protein (NSP) that is involved in vector transmission in nanoviruses but has no similar function in geminiviruses. Thanks to the recent discovery of aphid-transmitted geminiviruses, this prediction could be tested for the geminivirus alfalfa leaf curl virus (ALCV) and the nanovirus faba bean necrotic stunt virus (FBNSV) in their common vector, Aphis craccivora. Estimations of viral load in midgut and head of aphids, precise localization of viral DNA in cells of insect vectors and host plants, and virus transmission tests revealed that the pathway of the two viruses across the body of their common vector differs both quantitatively and qualitatively.
Assuntos
Afídeos/virologia , Coinfecção , Geminiviridae/fisiologia , Insetos Vetores/virologia , Nanovirus/fisiologia , Animais , DNA Viral , Geminiviridae/classificação , Hibridização in Situ Fluorescente , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Mucosa Intestinal/virologia , Nanovirus/classificação , Fenótipo , Doenças das Plantas/virologia , Vírus de Plantas/fisiologia , Saliva/virologiaRESUMO
The Geminiviridae family is one of the most successful and largest families of plant viruses that infect a large variety of important dicotyledonous and monocotyledonous crops and cause significant yield losses worldwide. This broad spectrum of host range is only possible because geminiviruses have evolved sophisticated strategies to overcome the arsenal of antiviral defenses in such diverse plant species. In addition, geminiviruses evolve rapidly through recombination and pseudo-recombination to naturally create a great diversity of virus species with divergent genome sequences giving the virus an advantage over the host recognition system. Therefore, it is not surprising that efficient molecular strategies to combat geminivirus infection under open field conditions have not been fully addressed. In this review, we present the anti-geminiviral arsenal of plant defenses, the evolved virulence strategies of geminiviruses to overcome these plant defenses and the most recent strategies that have been engineered for transgenic resistance. Although, the in vitro reactivation of suppressed natural defenses as well as the use of RNAi and CRISPR/Cas systems hold the potential for achieving broad-range resistance and/or immunity, potential drawbacks have been associated with each case.
Assuntos
Sistemas CRISPR-Cas , Geminiviridae/fisiologia , Interações Hospedeiro-Patógeno , Doenças das Plantas/imunologia , Imunidade Vegetal/genética , Interferência de RNA , Produtos Agrícolas/genética , Produtos Agrícolas/imunologia , Resistência à Doença/genética , Engenharia Genética , Doenças das Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/imunologiaRESUMO
The geminivirus capsid architecture is unique and built from twinned pseudo T=1 icosahedrons with 110 copies of the coat protein (CP). The CP is multifunctional. It performs various functions during the infection of a wide range of agriculturally important plant hosts. The CP multimerizes via pentameric intermediates during assembly and encapsulates the ssDNA genome to generate the unique capsid morphology. The virus capsid protects and transports the genome in the insect vector and plant host enroute to the plant nucleus for replication and the production of progeny. This review further explores CP:CP and CP:DNA interactions, and the environmental conditions that govern the assembly of the geminivirus capsid. This analysis was facilitated by new data available for the family, including three-dimensional structures and molecular biology data for several members. In addition, current and promising new control strategies of plant crop infection, which can lead to starvation for subsistence farmers, are discussed.
Assuntos
Proteínas do Capsídeo/metabolismo , Capsídeo/química , Capsídeo/metabolismo , Geminiviridae/genética , Geminiviridae/fisiologia , Animais , Livros , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Microscopia Crioeletrônica , Geminiviridae/química , Geminiviridae/ultraestrutura , Genoma Viral , Insetos Vetores/virologia , Modelos Moleculares , Doenças das Plantas/virologia , Conformação Proteica , Montagem de VírusRESUMO
BACKGROUND: Grapevine red blotch virus (GRBV) is a recently discovered DNA virus, which was demonstrated to be responsible for grapevine red blotch disease (GRBD). Its presence has been confirmed in the United States, Canada, Mexico, and South Korea in white and red Vitis vinifera cultivars, including Chardonnay. It has been shown that the three-cornered alfalfa treehopper (Spissistilus festinus) was able to both acquire the GRBV from a grapevine infected and transmit it to healthy grapevines in glasshouse conditions. Studies found that GRBD impacts fruit price, grapevine physiology, and grape berry composition and metabolism in red cultivars. This study evaluated the impact of GRBD on V. vinifera L. Chardonnay grape and wine composition and sensory properties from one vineyard during the 2014, 2015 and 2016 seasons. RESULTS: Grapes from symptomatic red blotch diseased grapevines were lower in total soluble solids, flavan-3-ol, and total phenolic content, and higher in flavonol content when compared to grapes from healthy grapevines. Wines made with grapes from symptomatic grapevines resulted mostly in lower ethanol content and higher pH when compared to wines made from healthy grapevines. Analysis of volatile compounds and descriptive analysis demonstrated that GRBD can impact wine style by altering aroma, flavor, and mouthfeel attributes. CONCLUSIONS: The impacts of GRBD on grape composition directly influenced wine chemistry. The decreased ethanol content impacted not only the levels of volatile compounds but the sensory perception during descriptive analysis. The extent of GRBD impact on the grape composition and wine composition and sensory attributes varied between seasons. © 2019 Society of Chemical Industry.
Assuntos
Frutas/química , Geminiviridae/fisiologia , Doenças das Plantas/virologia , Vitis/virologia , Vinho/análise , Vinho/virologia , Antocianinas/química , Antocianinas/metabolismo , Aromatizantes/química , Aromatizantes/metabolismo , Frutas/metabolismo , Humanos , Fenóis/química , Fenóis/metabolismo , Estações do Ano , Paladar , Vitis/química , Vitis/metabolismoRESUMO
Viruses constitute the largest group of emerging pathogens, and geminiviruses (plant viruses with circular, single-stranded DNA genomes) are the major group of emerging plant viruses. With their high potential for genetic variation due to mutation and recombination, their efficient spread by vectors, and their wide host range as a group, including both wild and cultivated hosts, geminiviruses are attractive models for the study of the evolutionary and ecological factors driving virus emergence. Studies on the epidemiological features of geminivirus diseases have traditionally focused primarily on crop plants. Nevertheless, knowledge of geminivirus infection in wild plants, and especially at the interface between wild and cultivated plants, is necessary to provide a complete view of their ecology, evolution, and emergence. In this review, we address the most relevant aspects of geminivirus variability and evolution in wild and crop plants and geminiviruses' potential to emerge in crops.
Assuntos
Geminiviridae/fisiologia , Doenças das Plantas/virologia , Vírus de Plantas/fisiologia , Plantas/virologia , Ecologia , Evolução Molecular , Geminiviridae/classificação , Geminiviridae/genética , Filogenia , Vírus de Plantas/classificação , Vírus de Plantas/genéticaRESUMO
Grapevine red blotch disease (GRBD) is a recently recognized viral disease that affects grapevines ( Vitis vinifera L.). Currently little is known about its impact on grape composition. This study focused on the impact of GRBD on grape primary and secondary metabolites (mainly phenolic compounds) of three Vitis vinifera L. cultivars during two seasons. Grapes from symptomatic red blotch diseased vines (RB (+)) mostly had lower concentration of total soluble solids (TSS) and higher titratable acidity (TA) levels when compared to grapes from healthy vines (RB (-)) at harvest. GRBD impacted grape phenolic composition by mostly decreasing anthocyanin and increasing flavonol and proanthocyanidin (PA) contents in berry skins. No major impacts were observed on seed phenolics. RB (+) grapes contained more amino and carboxylic acids, while RB (-) grapes contained more oligosaccharides, polyols, and some specific monosaccharides at harvest. The impact of GRBD on grape composition was variable and dependent on the cultivar, site, and season.
Assuntos
Frutas/química , Doenças das Plantas/virologia , Vitis/química , Antocianinas/análise , Cor , Frutas/virologia , Geminiviridae/fisiologia , Fenóis/análise , Proantocianidinas/análise , Sementes/química , Vitis/classificação , Vitis/virologiaRESUMO
Spread and in-field spatial patterns of vines infected with grapevine red blotch virus (GRBV) were documented in Oregon vineyards using field sampling, molecular diagnostics, and spatial analysis. Grapevine petiole tissue collected from 2013 to 2016 was tested using quantitative polymerase chain reaction for GRBV. At Jacksonville in southern Oregon, 3.1% of vines were infected with GRBV in 2014, and GRBV incidence reached 58.5% of study vines by 2016. GRBV-infected plants and GRBV-uninfected plants were spatially aggregated at this site in 2015, and infected plants were spatially associated between years 2015 and 2016. In a southern Oregon vineyard near Talent, 10.4% of vines were infected with GRBV in 2014, and infection increased annually to 21.5% in 2016. At Talent, distribution of the infected vines was spatially associated across all years. GRBV infection was highest at Yamhill, in the Willamette Valley, where 31.7% of the tested vines had GRBV infection in 2014. By 2016, 59.2% of the vines tested positive for GRBV. Areas of aggregation increased and were spatially associated across all years. From 2013 to 2015, GRBV was not detected at Milton-Freewater in eastern Oregon. Spatial patterns of GRBV infection support evidence of spread by a mobile insect vector. GRBV is a significant threat to Oregon wine grape production because of its drastic year-over-year spread in affected vineyards.