Identification and partial characterization of a <Emphasis Type="Italic">Carica papaya</Emphasis>-infecting isolate of <Emphasis Type="Italic">Alfalfa mosaic virus</Emphasis> in Brazil

A Carica papaya plant with severe yellow leaf mosaic, leaf distortion, and systemic necrosis was found in the municipality of Piracicaba, state of São Paulo, Brazil. Transmission electron microscopy (TEM) analysis revealed the presence of potyvirus-like particles and bacilliform particles similar to those of the Alfamovirus genus. The potyvirus was identified as Papaya ringspot virus-type P (PRSV-P). Biological, serological, and molecular studies confirmed the bacilliform virus as an isolate of Alfalfa mosaic virus (AMV). Partial nucleotide and amino acid sequences of the coat protein gene of this AMV isolate shared 97–98% identity with the AMV isolates in the GenBank database. This report is the first of the natural infection of papaya plants by AMV.     

Important genetic diversity of ‘<Emphasis Type="Italic">Candidatus</Emphasis> Phytoplasma solani’ related strains associated with bois noir grapevine yellows and planthoppers in Azerbaijan

Bois noir (BN) is an important grapevine yellows endemic to the Euro-Mediterranean basin caused by ‘Candidatus Phytoplasma solani’ (‘Ca. P. solani’), a non culturable plant pathogenic Mollicute. Bois noir symptoms could be associated with ‘Ca. P. solani’ in two Azerbaijanian vineyards where disease incidence and severity were recorded for five local Vitis vinifera cultivars. In order to gain insight into the epidemiology of Bois noir in Azerbaijan, ‘Ca. P. solani’ isolates infecting plants were characterized by multi-locus sequence analysis and their secY and stamp gene sequences compared to that of the strains detected in other plants and in local Cixiidae planthoppers. Genotypes were determined for two non-ribosomal house-keeping genes, namely tuf and secY, as well as two variable markers namely Stamp and mleP1 genes, that respectively encode the antigenic membrane protein AMP and a 2-Hydroxycarboxylate transporter. The Azerbaijanian BN phytoplasma isolates corresponded to three tufB and secY genotypes. A finer differentiation of Azerbaijanian ‘Ca. P. solani’ isolates was obtained with mleP1 as five different mleP1 genetic variants were found. Finally, Stamp gene allowed differentiating four new genotypes in grapevine among the 10 new Stamp genotypes detected in various plants in Azerbaijan. The preliminary survey for infected insects conducted in northern Azerbaijan, led to the identification of Hyalesthes obsoletus and Reptalus noahi as potential vectors for two ‘Ca. P. solani’ new genotypes phylogenetically distant from the known genetic clusters. Altogether these results indicate an important genetic diversity of BN phytoplasmas in Azerbaijan that certainly result from spread through local insect vectors.     

Comparison among Japanese isolates of <Emphasis Type="Italic">Pseudomonas savastanoi</Emphasis> pv. <Emphasis Type="Italic">savastanoi</Emphasis>, causal agent of olive knot disease

Olive knot disease in Japan was first reported in Shizuoka Prefecture in 2014, and the causal agent was identified as Pseudomonas savastanoi pv. savastanoi. Subsequently, olive trees having knots were also found in Aichi and Kanagawa Prefectures in 2015, and the isolates from knots were also suspected to be P. savastanoi pv. savastanoi through preliminary examinations. Therefore, the Aichi and Kanagawa isolates were identified through comparison of isolates from three prefectures. Phylogenic analysis based on 16S rDNA and housekeeping genes (gyrB, rpoD, gltA and gap1) revealed that the isolates belonged to the same cluster as the pathotype strain, ICMP4352^PT. The iaaM, H and L genes, which are involved in promotion of symptoms, and the ina gene coding the ice nucleation protein, were detected by PCR from all the isolates. In rep-PCR (ERIC and REP) analyses, the isolates yielded DNA fragment-banding patterns that were nearly identical to that of ICMP4352^PT, but slight variations in banding patterns were observed among them. In a pathogenicity test, the isolates formed distinct knots on olive and pink jasmine. Phenotypic properties of the isolates were almost identical to those of ICMP4352^PT, with the exception of d-sorbitol utilization. Consequently, Aichi and Kanagawa isolates from olive were identified as P. savastanoi pv. savastanoi, and several genetic diversities in terms of rep-PCR were found in the Japanese population of P. savastanoi pv. savastanoi, indicating their heterogeneity.     

Identification and characterization of <Emphasis Type="Italic">Colletotrichum</Emphasis> spp. associated with chili anthracnose in peninsular Malaysia

Anthracnose fruit rot caused by Colletotrichum spp. is a serious post-harvest disease of chili fruits (Capsicum spp.). One hundred-thirty isolates of Colletotrichum spp. were isolated from anthracnose of green and red cayenne pepper (Capsicum annuum) and bird’s eye chili (Capsicum frutescens). The isolates were morphologically identified as Colletotrichum acutatum sensu lato (62 isolates), Colletotrichum truncatum (54 isolates), and Colletotrichum gloeosporioides sensu lato (14 isolates). Molecular identification and phylogenetic analyses were based on internal transcribed spacer regions, β-tubulin, actin, and glyceraldehyde-3-phosphate dehydrogenase genes, and the isolates were re-identified as C. scovillei (58 isolates), C. truncatum (54 isolates), C. siamense (11 isolates), C. fioriniae (four isolates), and C. fructicola (3 isolates). Maximum likelihood trees using combined sequences showed that isolates of the same species grouped in the same main clade with the isolates used for comparison. Pathogenicity testing showed that the tested isolates from each species were pathogenic towards green and red Capsicum annuum and Capsicum frutescens upon treatment of wounded fruit, using both the mycelial plug and conidial suspension methods. Only five isolates of C. truncatum and seven isolates of C. scovillei were found to be pathogenic upon treatment of unwounded fruit. The occurrence of five Colletotrichum spp. (C. siamense, C. fructicola, C. scovillei, C. fioriniae, and C. truncatum) associated with chili anthracnose in Peninsular Malaysia indicates that correct species identification is important to formulate not only effective disease management, but also effective quarantine policy.     

Identification of <Emphasis Type="Italic">Pseudoperonospora cubensis</Emphasis> using real-time PCR and high resolution melting (HRM) analysis

To develop a molecular method to identify Pseudoperonospora cubensis in cucumber leaves with signs of downy mildew, we compared the nucleotide sequences of ribosomal DNA-internal transcribed spacer, cytochrome oxidase II, and β-tubulin genes of P. cubensis and P. humuli isolates. Seven single nucleotide polymorphisms (SNPs) distinguished P. cubensis and P. humuli based on variations in β-tubulin sequences, and one specific primer set was designed for further analysis. Real-time PCR and high resolution melting analysis showed that the primer set can be used to specifically identify P. cubensis in cucumber leaves with downy mildew.     

Unique clones of the pitch canker fungus, <Emphasis Type="Italic">Fusarium circinatum,</Emphasis> associated with a new disease outbreak in South Africa

Pitch canker of pines is caused by the fungus Fusarium circinatum. In South Africa, this pathogen has mostly been a nursery problem. From 2005, however, outbreaks of pitch canker have been reported from established Pinus radiata and P. greggii in the Western and Eastern Cape Provinces. Most recently, pitch canker-like symptoms were observed on 10-year-old P. greggii trees in a plantation in the midlands of the KwaZulu-Natal (KZN) Province. The aim of this study was to: (i) identify the causal agent of the observed symptoms, (ii) determine the genetic diversity, and (iii) the mode of reproduction of this fungal population. Furthermore, the aggressiveness of isolates from these trees was compared with that of isolates obtained previously from P. patula in South Africa. Isolates from the P. greggii trees in KZN were confirmed as F. circinatum based on both morphology and DNA sequence analyses. Microsatellite marker analyses revealed the presence of five genotypes of F. circinatum, not previously reported from other plantations in South Africa, with one of these genotypes being dominant. These genotypes were all pathogenic to P. patula and P. elliottii. No evidence of sexual reproduction was detected in the KZN population of the fungus. This was consistent with the fact that isolates from P. greggii were all of the MAT-2 mating type, in contrast to previously collected isolates from across South Africa that included both mating types. The results suggest that the outbreak of pitch canker on P. greggii in KZN represents a separate introduction of F. circinatum into the region with important implications for managing the disease.     

Pathogenicity,Morpho-Species and Mating Types of <Emphasis Type="Italic">Alternaria</Emphasis> spp. causing Alternaria blight in <Emphasis Type="Italic">Pistacia</Emphasis> spp. in Turkey

Alternaria genus includes many plant pathogens on numerous hosts, causing leaf spots, rots and blights. Alternaria blight has been observed as one of the important fungal diseases of pistachio (Pistacia vera L.) as well as its wild relatives (P. terebinthus, P. lentiscus, P. khinjuk, P. atlantica, P. mutica) in Turkey. Alternaria species were sampled from Pistacia spp. hosts from different geographic regions in Turkey during field trips in late spring to early fall of 2013. Alternaria blight symptoms were observed mainly on fruits and rarely on leaves. Four hundred and twenty two of the isolates were morphologically defined as A. alternata, A. tenuissima, A. arborescens and also intermediate morpho-species between A. alternata/A. arborescens. Pathogenicity of the isolates was confirmed with host inoculations on detached fruits. Mating types of 270 isolates of Alternaria spp. from the collection were identified using a PCR-based mating type assay that amplifies either a MAT1-1 or a MAT1-2 fragment from the mating locus. Although a strongly clonal population structure was expected due to the putative asexual reproduction of these fungi, both idiomorphs were detected at equal frequencies at several different spatial scales. The distribution of mating types within each geographic region, within host species as well as in overall collection was not significantly different from 1:1. Amplified fragments of partial idiomorph sequences were obtained for representative isolates. Parsimony trees were depicted based on sequence data of mating type genes for these representative isolates as well as some other Alternaria species obtained by Genebank. Several point mutations presented a few clusters which are supported by high bootsrapped values. The Alternaria blight disease agents both from cultivated and wild hosts were pathogenic on pistachio which may cause difficulties to control the disease because of extensity of pathogen sources. Besides, equal mating type distribution of the pathogen at both geographic and host species levels suggests a potential for sexual reproduction of Alternaria spp. in Turkey.     

Transgene-mediated resistance to <Emphasis Type="Italic">Papaya ringspot virus</Emphasis>: challenges and solutions

Global papaya production is severely affected by papaya ringspot disease caused by Papaya ringspot virus (PRSV). Management of this potyvirus is challenging, due to 1) its non-persistent transmission by numerous aphid species and 2) the diversity of PRSV strains that exists within a country or between different geographical regions. Papaya cultivars with transgenic resistance have reduced the impact of the disease. There are no effective alternatives to transgenic resistance available in areas where disease pressure is high. In Hawaii, transgenic papayas such as “SunUp” and “Rainbow” have remained resistant to PRSV more than two decades saving the commercial papaya industry. Following the success in Hawaii, researchers from other countries have focused on developing PRSV-resistant transgenic papaya. These transgenic cultivars often demonstrated an initial transitory resistance that was ultimately overcome by the virus. For other cases, resistance was inconsistent. That is, some transgenic lines were resistant while others were not. Transgenic cultivars are now losing PRSV-resistance for various reasons in China and Taiwan. In this review, we present an update on work with transgenic papaya with resistance to PRSV. The focus is on factors affecting transgenic resistance in papaya and our attempt to explain why the Hawaiian scenario of complete and durable resistance has not been replicated in other regions. The utilization of more recent technologies to the development of virus resistance in papaya is also discussed.     

Studies on the selective fungitoxicity of aliphatic amines

A comparison of the uptake of simple (C₁–C₄) aliphatic amines byPenicillium digitatum revealed that the fungitoxicity of (?)sec-butylamine [(?)SBA] was not due to its accumulation by hyphae since (+)SBA was accumulated to the same extent and methylamine, which showed negligible antifungal activity, accumulated to twice the level of SBA. Amines with a secondary alkyl structure were resistant to fungal metabolism, whereas primary amines were degraded to a significant extent byP. digitatum during a 4 h incubation period.(?)SBA accumulated in the fresh hyphae ofP. digitatum to a level 24 times higher than that in the culture medium containing 1 μmol ml^?1; most of the SBA effluxed from the hyphae when transferred to fresh culture medium minus SBA. SBA did not accumulate when hyphae were incubated in N₂ or in the presence of respiratory inhibitors. The absorption and accumulation of SBA is characteristic of active transport.Penicillium species and biotypes that are sensitive to SBA did not accumulate more (?)SBA than resistant fungi. SBA-resistant biotypes ofP. digitatum accumulated SBA to twice the level of SBA-sensitive biotypes, but did not accumulate pyruvate in the hyphae, which is characteristic of SBA-altered metabolism.No evidence was found to implicate exclusion or metabolic detoxification as mechanisms of SBA resistance. More probably, resistance involves cytoplasmic sequestration of SBA or low affinity of the biochemical target, pyruvic dehydrogenase.     

Attempts to eradicate graft-transmissible infections through somatic embryogenesis in <Emphasis Type="Italic">Citrus</Emphasis> ssp. and analysis of genetic stability of regenerated plants

Ability to detect Pseudocercospora macadamiae infection in macadamia husk at least four months before symptoms become visible will aid the development of disease control measures. This study examined the distinctness of P. macadamiae within the phylogenetic lineages of the genus Pseudocercospora. In addition, we developed two quantitative PCR (qPCR) assays, as rapid diagnostic tools, for early detection and quantification of P. macadamiae in planta. Phylogenetic analysis of concatenated sequences of four gene loci (large subunits, internal transcribed spacer (ITS), translation elongation factor 1-alpha (TEF-1α) and actin of 47 P. macadamiae isolates showed that P. macadamiae is a distinct species in the genus Pseudocercospora. P. macadamiae isolates were partitioned into subunits in the cluster but the grouping of the isolates was regardless of location. Nucleotide diversity (0.02) and the coefficient of genetic differentiation (0.07) were low in the P. macadamiae population. Two qPCR primer sets, based on ITS (PMI) and TEF-1α (PME) were designed that consistently amplified P. macadamiae in fungal cultures (Ct = 16.93 ± 0.11 and Ct = 21.20 ± 0.11, respectively) and in planta (Ct = 32.36 ± 0.28 and Ct = 38.07 ± 1.20, respectively). The PMI primers also detected species in the genus Pseudocercospora, while PME was more specific and robust for quantification of P. macadamiae. Both primer sets detected P. macadamiae in asymptomatic tissue samples and strongly differentiated various stages of disease progression, which revealed approximately 10-fold increase in fungal biomass between each consecutive stage of symptom development.     

Races of <Emphasis Type="Italic">Phytophthora infestans</Emphasis> isolated from potato in Hokkaido,Japan

The virulence of 29 isolates of Phytophthora infestans collected in potato fields in Hokkaido, Japan, in 2013 and 2014, was tested for race identification. Thirteen different races were identified, each of which had five to eight virulence factors. All of the isolates caused a virulent reaction against plants with R1 and R7, and most of the isolates caused a virulent reaction against plants with R3, R4, R10, and R11. On the other hand, no isolate was virulent against plants with R9. These results demonstrate that the current Japanese P. infestans population is more complex than the population in the 1990s from the viewpoint of race.     

Association of <Emphasis Type="Italic">Pantoea ananatis and Pantoea agglomerans</Emphasis> with leaf spot disease on ornamental plants of Araceae Family

During a survey in 2011–2012, three ornamental plants of Araceae namely Aglaonema nitidum, Syngonium podophyllum and Dieffenbachia amoena showing foliar disease symptoms were collected from central region of Iran. Infected plants exhibited spots on their leaves which appeared as yellow and water-soaked with chlorotic haloes and necrotic center. To investigate the etiology of this disorder, symptomatic leaves were collected from affected plants and six bacterial strains (B2Y, J3Y, SY, E60Y, E68Y and E5MM) were isolated and identified as Pantoea ananatis or P. agglomerans based on morphological, physiological, biochemical and molecular characters. The pathogenicity tests of the isolates demonstrated that they were not host specific. Furthermore, 16S rRNA gene sequencing revealed that the strains were phylogenetically closely related to genus Pantoea. Multilocus sequence analysis (MLSA) of concatenated partial atpD, gyrB and rpoB gene sequences of the six isolates showed a high similarity of B2Y, J3Y, and SY strains to P. ananatis and also of E60Y, E5MM and E68Y strains to P. agglomerans. These results were confirmed by phylogenetic analysis. To the best of our knowledge, this is the first report of leaf spot and necrosis of A. nitidum, S. podophyllum and D. amoena caused by the genus Pantoea.     

Leaf blast disease reduction by rice-phyllosphere actinomycetes producing bioactive compounds

Fungal leaf blast, caused by Pyricularia oryzae, is a devastating disease of rice plants that annually causes severe production losses worldwide and is one of the top 10 fungal diseases that threaten global food security. Thus, a reliable control strategy against this disease is essential. In this study, the antagonistic activity of indigenous phyllosphere actinomycetes was elucidated against P. oryzae in vitro and in planta to develop an efficient, effective and environmental friendly approach to protect rice plants against P. oryzae. Of 75 isolates of actinomycetes isolated from the rice phyllosphere, 18 isolates inhibited P. oryzae by >45%. According to analysis of their 16 S rRNA gene sequences, the majority of the 18 isolates belonged to Streptomyces genera; others were identified as belonging to Saccharothrix, Gordonia, or Lentzea. Isolates that potentially produced a bioactive compound(s) were identified among the 18 isolates: 17 isolates (94.44%) had a domain marker for nonribosomal peptide synthetase (NRPS) gene and 12 (66.67%) had type-I polyketide synthase (PKS) gene in their corresponding genome. Interestingly, isolates JSN1.9, SKB2.14, and SKB2.3 suppressed disease suppression by approximately 88%. To our knowledge, this is the first report on the application of rice-phyllosphere actinomycetes producing bioactive compounds to control leaf blast disease in Indonesia. Thus, these findings have escalated the potential application of phyllosphere actinomycetes as a supreme biocontrol agent against fungal leaf blast disease.     

Biochemical,physiological, and molecular characterization of <Emphasis Type="Italic">Dickeya dianthicola</Emphasis> (formerly named <Emphasis Type="Italic"> Erwinia chrysanthemi</Emphasis>) causing potato blackleg disease in Japan

The taxonomic assignment of Japanese potato blackleg isolates of Dickeya spp. has not been confirmed after the changes in their former name, Erwinia chrysanthemi. Therefore, we investigated and identified 23 representative isolates of Dickeya spp. from symptomatic stems of potatoes in Japan, with biochemical tests and phylogenetic sequence analysis using recA, dnaX, rpoD, gyrB, and 16S rDNA sequences. Results of our biochemical tests showed that all isolates can be assigned to phenon 5 and biovar 1, which are associated with D. dianthicola. Based on the recA, dnaX, rpoD, gyrB, and 16S rDNA sequences, all isolates are in the same clade with D. dianthicola and were clearly distinguished from D. chrysanthemi, D. dadantii, D. dadantii subsp. dieffenbachiae, D. solani, D. zeae, and D. paradisiaca. Therefore, we conclude that Dickeya spp. isolated from potatoes with blackleg symptoms in Japan are D. dianthicola.     

Genotypic and phenotypic variability of <Emphasis Type="Italic">Pectobacterium</Emphasis> strains causing blackleg and soft rot on potato in Turkey

Pectinolytic bacteria were isolated from 48 potato plants showing the symptoms of blackleg and collected in different fields of commercial potato production areas at Samsun, Amasya, Corum and Yozgat provinces in Turkey in 2015. The survey resulted in the isolation of 26 pectinolytic strains that belonged to P. atrosepticum, P. carotovorum subsp. brasiliense, P. carotovorum subsp. carotovorum and P. parmentieri species based on molecular identification with species-specific PCR and phenotypic characterization. The identified strains indicated typical biochemical characteristics of the assigned species. For 16 representative Pectobacterium isolates 10 unique rep-PCR band patterns were obtained. The 16S rRNA and recA and gapA gene fragment sequencing confirmed the species identity of the isolates. The phenotypic characterization of the strains revealed that for all assays but one (cellulase, protease activity, swimming but not swarming), the tested Pectobacterium species were significantly different from each other proving the diversity of the strains belonging to these genera. Recent outbreaks of blackleg and/or soft rot in potato production areas in Turkey may pose a threat on other crops, as tomato, pepper, cucumber, onion, cabbage, broccoli and sugar beet are cultivated in the same provinces.     

Identification of pathogenic fungi and preliminary screening for resistance in <Emphasis Type="Italic">Jatropha curcas</Emphasis> L. germplasm

Sexual reproduction in fungi is controlled by mating type genes, which are located at the MAT locus. In this study, we investigated the structure of this locus in the phytopathogenic fungus Phyllosticta citricarpa, the causal agent of citrus black spot disease. Despite intensive study, its sexual state has never been observed in single-spore culture. Through analysis of the genome sequences of two individual P. citricarpa isolates, the sequence of the DNA lyase gene was identified and, as previously reported in the literature, the mating type genes were located in the 3′ flanking region of this gene. The results suggested that P. citricarpa is heterothallic, owing to the exclusive presence of the MAT1–1 or MAT1–2 gene in individual strains. In order to characterize the MAT locus, we designed primers to amplify this region. P. citricarpa was found to have complete and apparently functional copies of MAT genes, containing α-1 and HMG domains, present in different isolates. In addition to MAT1–2-1 and MAT1–1-1 genes, the MAT1–1-4 gene was located in the 5′ flanking region of the MAT1–1-1 gene and the MAT1–2-5 gene was located in 5′ flanking region of the MAT1–2-1 gene. A multiplex PCR protocol was also developed to differentiate P. citricarpa idiomorphs, which can be used in distribution and incidence studies of mating type strains, in order to determine the occurrence of sexual reproduction and to facility crossing studies. Furthermore, in Brazil, the two idiomorphs occur in a 1:1 ratio, which is expected in sexually reproducing populations.     

A climatic risk analysis of the threat posed by the South American leaf blight (SALB) pathogen <Emphasis Type="Italic">Microcyclus ulei</Emphasis> to major rubber producing countries

In 2010, symptoms of cobweb disease were observed on cultivated Pleurotus eryngii crops in Spain. Based on morphological and genetic analyses, the causal agent of cobweb was identified as Cladobotryum mycophilum. Pathogenicity tests on fruit bodies were performed using conidial suspensions of three C. mycophilum isolates. The causal agent was re-isolated in 80–85 % of the fruit bodies inoculated internally and 15–40 % of those fruit bodies inoculated on the cap surface. The results pointed to a certain resistance of the P. eryngii cap surface to the mycelium of C. mycophilum. Two cropping trials inoculated with C. mycophilum were set up to evaluate the pathogenicity of the causal agent of cobweb in two casings. At the end of the growth cycle, 50–60 % of the inoculated blocks cased with mineral soil, and 20–33 % of the inoculated blocks cased with black peat showed cobweb symptoms. This difference in the appearance of the disease and its aggressiveness may be partly explained by different electrical conductivity values of the casing materials used. In vitro sensitivity of the C. mycophilum isolates and P. eryngii strains against four fungicides (chlorothalonil, prochloraz-Mn, thiabendazole and thiophanate-methyl) was assessed in radial growth experiments on fungicide-amended media. The most effective fungicides for inhibiting the in vitro growth of C. mycophilum were prochloraz-Mn and chlorothalonil, while prochloraz-Mn was also the most selective fungicide between P. eryngii and C. mycophilum, and chlorothalonil was the most toxic fungicide against the P. eryngii mycelium.     

Development of specific primers based on the genomes of <Emphasis Type="Italic">Penicillium</Emphasis> spp. for rapid detection of <Emphasis Type="Italic">Penicillium digitatum</Emphasis> among fungal isolates in citrus

Specific primers targeting Penicillium digitatum were developed based on fungal genes RPB1 and cmd, which are conserved among the genomes of Penicillium spp. The specific primers were designed based on the mutational sites in the homologous regions of the conserved genes. The results indicated that primer pairs RPB1–1 and cmd-3 were specific enough to distinguish Penicillium digitatum (N1) from Penicillium chrysogenum (Q), Penicillium italicum (A10) and Penicillium expansum (L) when the DNA samples were diluted 100-fold. To further verify the effectiveness and specificity of the two primer pairs RPB1–1 and cmd-3, 38 strains of fungal isolates from sources related to citrus were detected using both primer pairs, and 14 candidate P. digitatum strains were identified. Then, the fourteen candidate P. digitatum strains were further identified as P. digitatum by morphological and molecular methods, which confirmed the detection accuracy and reliability of the specific primer pairs RPB1–1 and cmd-3 as molecular markers of P. digitatum. This work may significantly facilitate the rapid identification of P. digitatum in the citrus industry.     

Identification of herbaceous hosts of the <Emphasis Type="Italic">Grapevine Pinot gris virus</Emphasis> (GPGV)

Grapevine Pinot gris Virus (GPGV) is a single stranded RNA of the genus Trichovirus infecting grapevine (Vitis vinifera) and associated with stunting, chlorotic mottling and leaf deformation symptoms. During a monitoring of GPGV infection in vineyards of the Trentino region in Italy, we have detected the virus in the herbaceous plants Silene latifolia subsp. Alba (Mill.) (bladder campion) and Chenopodium album L. (white goosefoot), which showed symptoms of viral infection. The full-length GPGV RNA genome, amplified from these infected hosts, was sequenced and a phylogenetic analysis revealed that its closest relative is the strain SK13, recently isolated in Slovakia. Our results indicate that herbaceous plants can be considered as a reservoir for the GPGV virus. This finding is important for studying the epidemiological aspects of GPGV disease and to formulate appropriate control measures.