| genetic variability among flavescence dorée phytoplasmas from different origins in italy and france. | flavescence dorée is a devastating disease of grapevine widespread in several countries in eu such as france, italy and spain. genetic variability among 17 italian and 3 french fd strains was investigated by rflp analyses based on a fragment of the ribosomal protein operon and on the non-ribosomal dna fragment fd9. rflp analysis of the pcr amplified ribosomal protein fragment, coding for the 3' end of rpl22 and the entire rps3 genes, differentiated 4 rp-subgroups among the fd strains and 4 subgr ... | 2002 | 12144771 |
| effect of two strains of flavescence dorée phytoplasma on the survival and fecundity of the experimental leafhopper vector euscelidius variegatus kirschbaum. | we have investigated the influence on longevity and fecundity of flavescence dorée phytoplasma (fdp), the agent of a grapevine yellows disease, in the experimental vector euscelidius variegatus kirschbaum. late instar nymphs were exposed to one or the other of two strains of fdp (fd92 and fd2000) by feeding on infected broad bean (vicia faba l.) or on healthy broad bean or maize (zea mays l.) for an acquisition access period of 13 days. detection of fdp in individual insects was done with pcr as ... | 2005 | 16087002 |
| a novel bacteroidetes symbiont is localized in scaphoideus titanus, the insect vector of flavescence dorée in vitis vinifera. | flavescence dorée (fd) is a grapevine disease that afflicts several wine production areas in europe, from portugal to serbia. fd is caused by a bacterium, "candidatus phytoplasma vitis," which is spread throughout the vineyards by a leafhopper, scaphoideus titanus (cicadellidae). after collection of s. titanus specimens from fd-contaminated vineyards in three different areas in the piedmont region of italy, we performed a survey to characterize the bacterial microflora associated with this insec ... | 2006 | 16461701 |
| spatial distribution of nymphs of scaphoideus titanus (homoptera: cicadellidae) in grapes, and evaluation of sequential sampling plans. | the spatial distribution of the nymphs of scaphoideus titanus ball (homoptera cicadellidae), the vector of grapevine flavescence dorée (candidatus phytoplasma vitis, 16sr-v), was studied by applying taylor's power law. studies were conducted from 2002 to 2005, in organic and conventional vineyards of piedmont, northern italy. minimum sample size and fixed precision level stop lines were calculated to develop appropriate sampling plans. model validation was performed, using independent field data ... | 2006 | 16686162 |
| diffusion of the nearctic leafhopper scaphoideus titanus ball in europe: a consequence of human trading activity. | scaphoideus titanus ball is a nearctic leafhopper that was introduced for the first time in europe probably at the beginning of the 20th century. in europe, this species is a specialist on cultivated grapevines and is of great economic importance as the vector of flavescence dorée (fd), a grapevine yellows disease caused by candidatus phytoplasma vitis. the random amplified polymorphic dna (rapd) technique was employed to obtain genetic information about the diffusion and the structure of s. tit ... | 2007 | 17242963 |
| multilocus sequence typing confirms the close genetic interrelatedness of three distinct flavescence dorée phytoplasma strain clusters and group 16srv phytoplasmas infecting grapevine and alder in europe. | vineyards of southern france and northern italy are affected by the flavescence dorée (fd) phytoplasma, a quarantine pathogen transmitted by the leafhopper of nearctic origin scaphoideus titanus. to better trace propagation of fd strains and identify possible passage between the vineyard and wild plant compartments, molecular typing of phytoplasma strains was applied. the sequences of the two genetic loci map and uvrb-degv, along with the sequence of the secy gene, were determined among a collec ... | 2007 | 17468266 |
| grapevine yellows in northern italy: molecular identification of flavescence dorée phytoplasma strains and of bois noir phytoplasmas. | verify the presence and the molecular identity of phytoplasmas in northern and central italy vineyards where yellows diseases are widespread. | 2007 | 18045417 |
| a chromosome map of the flavescence doree phytoplasma. | the flavescence dorée phytoplasma (fd-p), a non-cultivable, plant-pathogenic bacterium of the class mollicutes, is the causal agent of a quarantine disease affecting vineyards of southern europe, mainly in southern france and northern italy. to investigate fd-p diversity and phytoplasma genetic determinants governing the fd-p life cycle, a genome project has been initiated. a physical map of the chromosome of fd-p strain fd92, purified from infected broad beans, was constructed by performing res ... | 2008 | 18451054 |
| insect injection and artificial feeding bioassays to test the vector specificity of flavescence dorée phytoplasma. | abstract the specificity of vector transmission of flavescence dorée phytoplasma (fdp) was tested by injecting fdp, extracted from laboratory-reared infective euscelidius variegatus, into specimens of 15 other hemipteran insect species collected in european vineyards. concentrations of viable phytoplasma extracts and latency in vectors were monitored by injection of healthy-reared e. variegatus leafhoppers. based on these preliminary results, insects were injected by using phytoplasma extracts t ... | 2006 | 18943154 |
| detection of phytoplasma by polymerase chain reaction of insect feeding medium and its use in determining vectoring ability. | a polymerase chain reaction (pcr)-based method was developed for the detection of phytoplasma in insect feeding medium (sucrose). a correlation was established between the transmissibility of flavescence dorée phytoplasma in the experimental leafhopper vector euscelidius variegatus and its detection by pcr in the insect feeding medium. however, phytoplasma were detected in the insects' bodies 3 weeks before they began to transmit. hence, pcr assays of the sucrose medium reflected phytoplasma vec ... | 2001 | 18944030 |
| comparing the spatial genetic structures of the flavescence dorée phytoplasma and its leafhopper vector scaphoideus titanus. | the nearctic leafhopper scaphoideus titanus ball is the vector of "flavescence dorée" phytoplasma (fdp) in european vineyards. we studied the genetic diversity and structure of s. titanus populations in france and of the fdp they carried. a total of 621 s. titanus individuals, sampled in 24 fdp-infected and uninfected vineyards, were genotyped using seven polymorphic microsatellite loci. the mean observed heterozygosity in s. titanus populations was between 0.364 and 0.548. there was evidence of ... | 2009 | 19464388 |
| genetic diversity of european phytoplasmas of the 16srv taxonomic group and proposal of 'candidatus phytoplasma rubi' | in addition to the grapevine flavescence dorée phytoplasmas, other members of the taxonomic group 16srv infect grapevine, alders, clematis and rubus in europe. in order to investigate which phytoplasmas constitute discrete, species-level taxa, several isolates were analysed comparing their 16s rrna gene sequence and a set of five house-keeping genes. whereas 16s rrna gene sequence identities were above 97.5 %, which is the proposed threshold to distinguish two 'candidatus phytoplasma' species, p ... | 2010 | 20889771 |
| [cloning and analysis of tuf and rp gene of the phytoplasma associated with jujube witches' -broom]. | jujube witches' -broom (jwb) is an important plant disease caused by phytoplasma. the major objective of our research was to classify jwb in beijing and hebei districts and to provide reference for classification in subgroup level. | 2010 | 21141464 |
| response of the vitis vinifera l. cv. 'nebbiolo' proteome to flavescence dorée phytoplasma infection. | flavescence dorée is a serious phytoplasma disease affecting grapevine in several european countries. we studied the interaction of flavescence dorée phytoplasma with its natural plant host by monitoring the effects of infection on the protein expression profile. among the 576 analyzed spots, 33 proteins were differentially regulated in infected grapevines. grouping into mips functional categories showed proteins involved in metabolism (21%), energy processes (9%), protein synthesis (3%), protei ... | 2010 | 21204249 |
| host plant determines the phytoplasma transmission competence of empoasca decipiens (hemiptera: cicadellidae). | phytoplasmas are phloem-restricted plant pathogens transmitted by leafhoppers, planthoppers, and psyllids (hemiptera). most known phytoplasma vectors belong to the cicadellidae, but many are still unknown. within this family, empoasca spp. (typhlocybinae) have tested positive for the presence of some phytoplasmas, and phytoplasma transmission has been proven for one species. the aim of this work was to investigate the ability of empoasca decipiens paoli in transmitting chrysanthemum yellows phyt ... | 2011 | 21510180 |
| lamp assay and rapid sample preparation method for on-site detection of flavescence dorée phytoplasma in grapevine. | in europe the most devastating phytoplasma associated with grapevine yellows (gy) diseases is a quarantine pest, flavescence dorée (fdp), from the 16srv taxonomic group. the on-site detection of fdp with an affordable device would contribute to faster and more efficient decisions on the control measures for fdp. therefore, a real-time isothermal lamp assay for detection of fdp was validated according to the eppo standards and miqe guidelines. the lamp assay was shown to be specific and extremely ... | 2014 | 26146413 |
| horizontal transmission of the symbiotic bacterium asaia sp. in the leafhopper scaphoideus titanus ball (hemiptera: cicadellidae). | bacteria of the genus asaia have been recently recognized as secondary symbionts of different sugar-feeding insects, including the leafhopper scaphoideus titanus, vector of flavescence dorée phytoplasmas. asaia has been shown to be localized in s. titanus gut, salivary glands and gonoducts and to be maternally transmitted to the progeny by an egg smearing mechanism. it is currently not known whether asaia in s. titanus is transmitted by additional routes. we performed a study to evaluate if asai ... | 2012 | 22376056 |
| heterologous expression and processing of the flavescence dorée phytoplasma variable membrane protein vmpa in spiroplasma citri. | flavescence dorée (fd) of grapevine is a phloem bacterial disease that threatens european vineyards. the disease is associated with a non-cultivable mollicute, a phytoplasma that is transmitted by the grapevine leafhopper scaphoideus titanus in a persistent, propagative manner. the specificity of insect transmission is presumably mediated through interactions between the host tissues and phytoplasma surface proteins comprising the so-called variable membrane proteins (vmps). plant spiroplasmas a ... | 2015 | 25879952 |
| genome sequence, prevalence and quantification of the first iflavirus identified in a phytoplasma insect vector. | the leafhopper euscelidius variegatus is a natural vector of chrysanthemum yellows phytoplasma (cy) and an efficient vector of flavescence dorée phytoplasma (fd) under laboratory conditions. during a transcriptome sequencing (rna-seq) project aimed at investigating the interactions between the insect and the two phytoplasmas, a 10,616-nucleotide-long contig with high sequence similarity to known picorna-like viruses was identified among the assembled insect transcripts. the discovery came totall ... | 2017 | 27888410 |
| evagreen real-time pcr protocol for specific 'candidatus phytoplasma mali' detection and quantification in insects. | in this paper the validation and implementation of a real-time pcr protocol based on ribosomal protein genes has been carried out for sensitive and specific quantification of 'candidatus (ca.) phytoplasma mali' (apple proliferation phytoplasma, app) in insects. the method combines the use of evagreen(®) dye as chemistry detection system and the specific primer pair rpap15f-mod/rpap15r3, which amplifies a fragment of 238 bp of the ribosomal protein rplv (rpl22) gene of app. primers specificity wa ... | 2013 | 23474195 |
| data processing of qualitative results from an interlaboratory comparison for the detection of "flavescence dorée" phytoplasma: how the use of statistics can improve the reliability of the method validation process in plant pathology. | a working group established in the framework of the euphresco european collaborative project aimed to compare and validate diagnostic protocols for the detection of "flavescence dorée" (fd) phytoplasma in grapevines. seven molecular protocols were compared in an interlaboratory test performance study where each laboratory had to analyze the same panel of samples consisting of dna extracts prepared by the organizing laboratory. the tested molecular methods consisted of universal and group-specifi ... | 2017 | 28384335 |
| acquisition of flavescence dorée phytoplasma by scaphoideus titanus ball from different grapevine varieties. | flavescence dorée (fd) is a threat for wine production in the vineyard landscape of piemonte, langhe-roero and monferrato, italy. spread of the disease is dependent on complex interactions between insect, plant and phytoplasma. in the piemonte region, wine production is based on local cultivars. the role of six local grapevine varieties as a source of inoculum for the vector scaphoideus titanus was investigated. fd phytoplasma (fdp) load was compared among red and white varieties with different ... | 2016 | 27649162 |
| metabolic consequences of infection of grapevine (vitis vinifera l.) cv. "modra frankinja" with flavescence dorée phytoplasma. | flavescence dorée, caused by the quarantine phytoplasma fdp, represents the most devastating of the grapevine yellows diseases in europe. in an integrated study we have explored the fdp-grapevine interaction in infected grapevines of cv. "modra frankinja" under natural conditions in the vineyard. in fdp-infected leaf vein-enriched tissues, the seasonal transcriptional profiles of 14 genes selected from various metabolic pathways showed an fdp-specific plant response compared to other grapevine y ... | 2016 | 27242887 |
| acibenzolar-s-methyl may prevent vector-mediated flavescence dorée phytoplasma transmission, but is ineffective in inducing recovery of infected grapevines. | acibenzolar-s-methyl (bth), a functional analogue of salicylic acid (sa), is known to elicit a systemic resistance across a broad range of plant-pathogen interactions, but so far it has not been tested against flavescence dorée (fdp), one of the most devastating grapevine diseases. the aim of this work was to evaluate the activity of bth in preventing fdp transmission by the insect vector and in inducing recovery of infected grapevines. | 2017 | 27116913 |
| rna-seq profile of flavescence dorée phytoplasma in grapevine. | the phytoplasma-borne disease flavescence dorée is still a threat to european viticulture, despite mandatory control measures and prophylaxis against the leafhopper vector. given the economic importance of grapevine, it is essential to find alternative strategies to contain the spread, in order to possibly reduce the current use of harmful insecticides. further studies of the pathogen, the vector and the mechanisms of phytoplasma-host interactions could improve our understanding of the disease. ... | 2014 | 25495145 |
| metabolic and transcript analysis of the flavonoid pathway in diseased and recovered nebbiolo and barbera grapevines (vitis vinifera l.) following infection by flavescence dorée phytoplasma. | flavescence dorée phytoplasma (fdp) infections seriously affect production and survival of grapevine. we analysed the changes in the flavonoid pathway occurring in two red cultivars, the highly susceptible barbera and the less susceptible nebbiolo, following fdp infection. a combination of metabolic and transcript analyses was used to quantify flavonoid compounds and expression of a set of genes involved in their biosynthesis. quantification of anthocyanins, flavonols, proanthocyanidins and rela ... | 2014 | 24689527 |
| a stage-structured model of scaphoideus titanus in vineyards. | we present a population model of the insect scaphoideus titanus ball, the leafhopper vector of flavescence dorée phytoplasma in vitis vinifera l. the model accounted for the stage-dependent s. titanus life cycle rates and timing, and vineyard settings such as surface area, plant density, and sampling characteristics. the model parameters were estimated against 13 independent cases of population counting in both laboratory and field conditions, and returned a correlation coefficient in the range ... | 2013 | 23575007 |
| novel aspects of grapevine response to phytoplasma infection investigated by a proteomic and phospho-proteomic approach with data integration into functional networks. | translational and post-translational protein modifications play a key role in the response of plants to pathogen infection. among the latter, phosphorylation is critical in modulating protein structure, localization and interaction with other partners. in this work, we used a multiplex staining approach with 2d gels to study quantitative changes in the proteome and phosphoproteome of flavescence dorée-affected and recovered 'barbera' grapevines, compared to healthy plants. | 2013 | 23327683 |
| mapping the phytoplasma chromosome. | physical and genetic mapping of the phytoplasma chromosome can be a useful tool in a genome sequencing project in order to assemble the in silico-predicted contigs robustly. mapping consists of four distinct steps: preparation of phytoplasma chromosomes from infected plants, single- and double-digestion of chromosomes with rare-cutting restriction enzymes, separation of large dna fragments by pulsed-field gel electrophoresis, and hybridization with various genetic markers. materials and methods ... | 2013 | 22987434 |
| reverse transcription-pcr for phytoplasma detection utilizing crude sap extractions. | phytoplasmas are routinely detected by nucleic acid-based techniques. these approaches rely on enriched phytoplasma dna extracts of good quality, following labor intensive and time-consuming purification protocols. here we describe a very rapid, specific, sensitive, and reliable method for flavescence dorée phytoplasma detection, based on real-time taqman(®) reverse transcription-pcr of the 16s rrna. the protocol is particularly useful for large-scale screening of vineyards and nurseries, pathog ... | 2013 | 22987424 |
| a real-time pcr detection system for the bois noir and flavescence dorée phytoplasmas and quantification of the target dna. | the real-time pcr detection system for grapevine yellows phytoplasmas described here is composed of two assays for group-specific detection of flavescence dorée (fd) and bois noir (bn) phytoplasmas and a universal phytoplasma assay. it uses hydrolysis minor groove binder probes (taqman-mgb). the addition of an assay for amplification of plant dna co-extracted with phytoplasma dna provides a further quality control for the dna extraction and pcr amplification for each sample. the detection system ... | 2013 | 22987422 |
| microsatellite and mitochondrial data provide evidence for a single major introduction for the neartic leafhopper scaphoideus titanus in europe. | scaphoideus titanus, a leafhopper native to north america and invasive in europe, is the vector of the flavescence dorée phytoplasma, the causal agent of the most important form of grapevine yellows in european vineyards. we studied 10 polymorphic microsatellite loci and a 623 bp fragment of the mitochondrial cytochrome oxidase ii gene in native s. titanus from north-eastern america and introduced european populations, to elucidate the colonization scenario. consistent with their recent history, ... | 2012 | 22629338 |