47 results on '"Bianco PA"'
Search Results
2. Role of Vitex agnus-castus as host plant of Hyalesthes obsoletus and 'Candidatus Phytoplasma solani' in North Italy
- Author
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Mori, N., Fabio, F., Moussa, A., Faccincani, M., Piscini, M., Posenato, G., and Bianco, Pa
- Published
- 2018
Catalog
3. Potential role of Euscelis incisus Kirschbaum and Dicranotropis hamata Boheman in the transmission of ‘Candidatus Phytoplasma solani’ to grapevine
- Author
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Mori, N., Quaglino, F., Sanna, Francesco, Filisetti, S., Faccincani, M., and Bianco, Pa
- Published
- 2018
4. Indagini sulla diffusione di GFLV (Grapevine Fanleaf Virus) e di ARMV (Arabis Mosaic Virus) in un vigneto dell’Oltrepò Pavese
- Author
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ZORLONI A, PRATI S, BIANCO PA, BELLI G., MANACHINI, Barbara Rosy Ines, ZORLONI A, MANACHINI B, PRATI S, BIANCO PA, and BELLI G
- Published
- 2006
5. Molecular diversity in Ca. Phytoplasma mali in Lombardia
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Casati, P, Stern, A, Spadone, P, Calvi, M, Bulgari, D, Bianco, Pa, and Belli, G
- Published
- 2007
6. Microflora endofita in viti affette da giallumi e soggette a recovery
- Author
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Bulgari, D, Casati, P, Quaglino, F, Belli, G, and Bianco, Pa
- Published
- 2007
7. Genetic Variability among flavescence dorie phytoplasmas from different origins in Italy and France
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Martini M., Botti S., Marcone C., Marzachl C., Casati P., Bianco Pa., Benedetti R., and Bertaccini A.
- Abstract
Flavescence doree 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 subgroups among the reference strains belonging to elm yellows group (16SrV). Sequencing and phylogenetic analysis of the same ribosomal protein DNA fragment validated the delineation of 4 distinct FD strain types derived by RFLP analyses. The results supported the differentiation based on analysis of the non-ribosomal DNA fragment FD9. The phylogenetic analysis further revealed relationships and a probable evolutionary trend among the FD strains and the other representatives of elm yellows group. All the FD strains together with the reference strains ALY, RuS and JWB formed a cluster very well distinct from the EY/ULW cluster. Moreover, ALY was shown to be more closely related to three FD strain types: the Lombardia/Piemonte, the French FD70, and the French FD88/ltalian FD-D strain clusters. more...
- Published
- 2002
8. Management of complications of first instance of hepatic trauma in a liver surgery unit: Portal vein ligation as a conservative therapeutic strategy
- Author
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Rocca Aldo, Andolfi Enrico, Zamboli Anna Ginevra Immacolata, Surfaro Giuseppe, Tafuri Domenico, Costa Gianluca, Frezza Barbara, Scricciolo Marta, Amato Maurizio, Bianco Paolo, Brongo Sergio, Ceccarelli Graziano, Giuliani Antonio, and Amato Bruno more...
- Subjects
portal vein ligation ,hepatic trauma ,therapeutic choice ,liver surgery unit ,management of complications ,Medicine - Abstract
According to the National Trauma Data Bank, the liver, after the spleen, is the first most injured organ in closed abdominal trauma.
- Published
- 2019
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9. ‘Candidatus Liberibacter europaeus’ sp. nov. that is associated with and transmitted by the psyllid Cacopsylla pyri apparently behaves as an endophyte rather than a pathogen
- Author
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Raddadi, N., Gonella, Elena, Camerota, Caterina, Pizzinat, ALAN CLAUDIO, Tedeschi, Rosemarie, Crotti, E., Mandrioli, M., Bianco, P. A., Daffonchio, D., Alma, Alberto, RADDADI N, GONELLA E, CAMEROTA C, PIZZINAT A, TEDESCHI R, CROTTI E, MANDRIOLI M, BIANCO PA, DAFFONCHIO D., and ALMA A more...
- Subjects
pear plants ,Molecular Sequence Data ,fungi ,food and beverages ,Sequence Analysis, DNA ,Hemiptera ,Pyrus ,RNA, Bacterial ,Rhizobiaceae ,RNA, Ribosomal, 16S ,DNA, Ribosomal Spacer ,Animals ,Cacopsylla pyri ,Candidatus Liberibacter ,Phylogeny ,Plant Diseases - Abstract
'Candidatus Liberibacter spp.' cause serious plant diseases. 'Candidatus Liberibacter asiaticus', 'Ca. L. americanus' and 'Ca. L. africanus' are the aetiological agents of citrus greening (Huanglongbing) in Asia, America and Africa. 'Candidatus Liberibacter solanacearum' causes diseases in Solanaceae in America and New Zealand. All four species are vectored by psyllid insects of different genera. Here, we show that the pear psyllid pest Cacopsylla pyri (L.) hosts a novel liberibacter species that we named 'Ca. Liberibacter europaeus'. It can bloom to high titres in the psyllid host, with more than 10(9) 16S rRNA gene copies per individual. Fluorescent in situ hybridization experiments showed that 'Ca. L. europaeus' is present in the host midgut lumen, salivary glands and Malpighian tubules. 'Candidatus L. europaeus' has a relatively high prevalence (51%) in C. pyri from different areas in the Piedmont and Valle d'Aosta regions in Italy and can be transmitted to pear plants in experimental transmission trials. However, even though high titres of the bacterium (more than 10(8) 16S rRNA gene copies g(-1) of pear plant tissue) could be detected, in the pear tissues no specific disease symptoms could be observed in the infected plants over a 6-month period. Despite liberibacters representing potential quarantine organisms, 'Ca. L. europaeus', first described in Italy and Europe, apparently behaves as an endophyte rather than a pathogen. more...
- Published
- 2011
10. Investigation on Flavescence Dorée in North-Western Italy Identifies Map-M54 (16SrV-D/Map-FD2) as the Only Phytoplasma Genotype in Vitis vinifera L. and Reveals the Presence of New Putative Reservoir Plants.
- Author
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Rigamonti IE, Salvetti M, Girgenti P, Bianco PA, and Quaglino F
- Abstract
Flavescence dorée (FD) is the most important phytoplasma-associated disease of the grapevine yellows complex in Europe. Recent studies highlighted a great genetic diversity within FD phytoplasma (FDp) strains and demonstrated that their diffusion is not related exclusively to the pathosystem including Vitis vinifera L. and Scaphoideus titanus but involves additional vectors and reservoir plants. This study aimed to investigate FD epidemiology in north-western Italy, with a particular focus on FDp hosts. During field surveys, leaf samples were collected from symptomatic grapevines and other symptomless plant species, and insects were collected within and around vineyards. Phytoplasmas belonging to the ribosomal group 16SrV were detected and typed using nested-PCR-based amplification and nucleotide sequence analyses of the map gene. All symptomatic grapevines were found to be infected by the FDp genotype M54, prevalent in S. titanus and also identified in other known and newly reported hosts. Interestingly, other FDp strains (M38, M50, M51, M121) and FDp-related strains (M39, M43, M48), never detected in grapevines, were largely identified in several known and newly reported host plants and insects including S. titanus . Such evidence confirmed the complexity of FD ecology, expanding the knowledge on the range of FDp host plants putatively involved in the disease spread. more...
- Published
- 2023
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11. Signaling Cross-Talk between Salicylic and Gentisic Acid in the ' Candidatus Phytoplasma Solani' Interaction with Sangiovese Vines.
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Nutricati E, De Pascali M, Negro C, Bianco PA, Quaglino F, Passera A, Pierro R, Marcone C, Panattoni A, Sabella E, De Bellis L, and Luvisi A
- Abstract
"Bois noir" disease associated with ' Candidatus Phytoplasma solani' seriously compromises the production and survival of grapevines ( Vitis vinifera L.) in Europe. Understanding the plant response to phytoplasmas should help to improve disease control strategies. Using a combined metabolomic and transcriptomic analysis, this work, therefore, investigated the phytoplasma-grapevine interaction in red cultivar Sangiovese in a vineyard over four seasonal growth stages (from late spring to late summer), comparing leaves from healthy and infected grapevines (symptomatic and symptomless). We found an accumulation of both conjugate and free salicylic acids (SAs) in the leaves of ' Ca . P. solani'-positive plants from early stages of infection, when plants are still asymptomatic. A strong accumulation of gentisic acid (GA) associated with symptoms progression was found for the first time. A detailed analysis of phenylpropanoids revealed a significant accumulation of hydroxycinnamic acids, flavonols, flavan 3-ols, and anthocyanin cyanidin 3- O -glucoside, which are extensively studied due to their involvement in the plant response to various pathogens. Metabolomic data corroborated by gene expression analysis indicated that phenylpropanoid biosynthetic and salicylic acid-responsive genes were upregulated in ' Ca . P. solani-positive plants compared to -negative ones during the observed period. more...
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- 2023
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12. Characterization of Italian Plasmopara viticola populations for resistance to oxathiapiprolin.
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Massi F, Torriani SF, Waldner-Zulauf M, Bianco PA, Coatti M, Borsa P, Borghi L, and Toffolatti SL
- Subjects
- Mutation, Italy, Plant Diseases, Disease Resistance, Fungicides, Industrial pharmacology, Oomycetes, Vitis
- Abstract
Background: Oxathiapiprolin is a novel fungicide and the first of the piperidinyl-thiazole-isoxazoline class to be discovered. This fungicide has been reported to have high activity against Plasmopara viticola, the grapevine downy mildew agent, and other plant-pathogenic oomycetes. In this study, the baseline sensitivity of Italian P. viticola populations towards oxathiapiprolin was established on 29 samples collected in 10 different viticultural areas. Two insensitive strains were characterized for their mechanism of resistance., Results: Oxathiapiprolin exhibited substantial inhibitory activity against 27 of the 29 populations tested, with EC
50 values ranging from a minimum of under 4 × 10-5 mg L-1 to over 4 × 10-1 mg L-1 , with an average value of 3.2 × 10-2 mg L-1 . Two stable suspected oxathiapiprolin-resistant mutants were isolated from population exhibiting reduced sensitivity, and sequenced for the oxathiapiprolin target gene PvORP1. The comparison with wild-type isolates revealed that the resistant isolates possessed a heterozygous mutation causing the amino acid substitution N837I, recently reported in the literature., Conclusion: The results obtained indicate a risk for Italian P. viticola populations to develop resistance to oxathiapiprolin in association with the N837I mutation at PvORP1. Anti-resistance strategies should be carefully implemented and the sensitivity levels to this molecule should be monitored accurately in future to preserve its effectiveness. © 2022 Society of Chemical Industry., (© 2022 Society of Chemical Industry.) more...- Published
- 2023
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13. Disease Forecasting for the Rational Management of Grapevine Mildews in the Chianti Bio-District (Tuscany).
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Maddalena G, Marone Fassolo E, Bianco PA, and Toffolatti SL
- Abstract
Downy and powdery mildews are major grapevine diseases. In organic viticulture, a few fungicides with protectant activities (copper and sulphur in particular) can be used, and their preventative application frequently leads to unneeded spraying. The adoption of an epidemiological disease forecasting model could optimise the timing of treatments and achieve a good level of disease protection. In this study, the effectiveness of the EPI (Etat Potentiel d'Infection) model in predicting infection risk for downy and powdery mildews was evaluated in nine organic vineyards located in Panzano in Chianti (FI), over a 2-year period (2020-2021). The reliability of the EPI model was investigated by comparing the disease intensities, the number of fungicide sprayings, the quantities of the fungicides (kg/ha), and the costs of the treatment achieved, with or without the use of the model, in a vineyard. The results obtained over two seasons indicated that, in most cases, the use of the EPI model accurately signalled the infection risk and allowed for a reduction in the frequency and cost of spraying, particularly for powdery mildew control (-40% sprayings, -20% costs compared to the farmer's schedule), without compromising crop protection. The use of the EPI model can, therefore, contribute to more-sustainable disease management in organic viticulture. more...
- Published
- 2023
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14. Influence of Nitrogen on Grapevine Susceptibility to Downy Mildew.
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Marcianò D, Ricciardi V, Maddalena G, Massafra A, Marone Fassolo E, Masiero S, Bianco PA, Failla O, De Lorenzis G, and Toffolatti SL
- Abstract
Downy mildew, caused by the obligate parasite Plasmopara viticola , is one of the most important threats to viticulture. The exploitation of resistant and susceptibility traits of grapevine is one of the most promising ways to increase the sustainability of disease management. Nitrogen (N) fertilization is known for influencing disease severity in the open field, but no information is available on its effect on plant-pathogen interaction. A previous RNAseq study showed that several genes of N metabolism are differentially regulated in grapevine upon P. viticola inoculation, and could be involved in susceptibility or resistance to the pathogen. The aim of this study was to evaluate if N fertilization influences: (i) the foliar leaf content and photosynthetic activity of the plant, (ii) P. viticola infectivity, and (iii) the expression of the candidate susceptibility/resistance genes. Results showed that N level positively correlated with P. viticola infectivity, confirming that particular attention should be taken in vineyard to the fertilization, but did not influence the expression of the candidate genes. Therefore, these genes are manipulated by the pathogen and can be exploited for developing new, environmentally friendly disease management tools, such as dsRNAs, to silence the susceptibility genes or breeding for resistance. more...
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- 2023
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15. Biocontrol Potential of Endophytic Plant-Growth-Promoting Bacteria against Phytopathogenic Viruses: Molecular Interaction with the Host Plant and Comparison with Chitosan.
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Shahzad GI, Passera A, Maldera G, Casati P, Marcello I, and Bianco PA
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- Plant Diseases microbiology, Pseudomonas syringae, Nicotiana microbiology, Chitosan pharmacology, Cucumovirus genetics, Cytomegalovirus Infections, Potexvirus genetics
- Abstract
Endophytic plant-growth-promoting bacteria (ePGPB) are interesting tools for pest management strategies. However, the molecular interactions underlying specific biocontrol effects, particularly against phytopathogenic viruses, remain unexplored. Herein, we investigated the antiviral effects and triggers of induced systemic resistance mediated by four ePGPB ( Paraburkholderia fungorum strain R8, Paenibacillus pasadenensis strain R16, Pantoea agglomerans strain 255-7, and Pseudomonas syringae strain 260-02) against four viruses (Cymbidium Ring Spot Virus-CymRSV; Cucumber Mosaic Virus-CMV; Potato Virus X-PVX; and Potato Virus Y-PVY) on Nicotiana benthamiana plants under controlled conditions and compared them with a chitosan-based resistance inducer product. Our studies indicated that ePGPB- and chitosan-treated plants presented well-defined biocontrol efficacy against CymRSV and CMV, unlike PVX and PVY. They exhibited significant reductions in symptom severity while promoting plant height compared to nontreated, virus-infected controls. However, these phenotypic traits showed no association with relative virus quantification. Moreover, the tested defense-related genes ( Enhanced Disease Susceptibility-1 ( EDS1 ), Non-expressor of Pathogenesis-related genes-1 ( NPR1 ), and Pathogenesis-related protein-2B ( PR2B )) implied the involvement of a salicylic-acid-related defense pathway triggered by EDS1 gene upregulation. more...
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- 2022
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16. Real-Time On-Site Diagnosis of Quarantine Pathogens in Plant Tissues by Nanopore-Based Sequencing.
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Marcolungo L, Passera A, Maestri S, Segala E, Alfano M, Gaffuri F, Marturano G, Casati P, Bianco PA, and Delledonne M
- Abstract
Rapid and sensitive assays for the identification of plant pathogens are necessary for the effective management of crop diseases. The main limitation of current diagnostic testing is the inability to combine broad and sensitive pathogen detection with the identification of key strains, pathovars, and subspecies. Such discrimination is necessary for quarantine pathogens, whose management is strictly dependent on genotype identification. To address these needs, we have established and evaluated a novel all-in-one diagnostic assay based on nanopore sequencing for the detection and simultaneous characterization of quarantine pathogens, using Xylella fastidiosa as a case study. The assay proved to be at least as sensitive as standard diagnostic tests and the quantitative results agreed closely with qPCR-based analysis. The same sequencing results also allowed discrimination between subspecies when present either individually or in combination. Pathogen detection and typing were achieved within 13 min of sequencing owing to the use of an internal control that allowed to stop sequencing when sufficient data had accumulated. These advantages, combined with the use of portable equipment, will facilitate the development of next-generation diagnostic assays for the efficient monitoring of other plant pathogens. more...
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- 2022
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17. RNAi of a Putative Grapevine Susceptibility Gene as a Possible Downy Mildew Control Strategy.
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Marcianò D, Ricciardi V, Marone Fassolo E, Passera A, Bianco PA, Failla O, Casati P, Maddalena G, De Lorenzis G, and Toffolatti SL
- Abstract
Downy mildew, caused by the oomycete Plasmopara viticola , is one of the diseases causing the most severe economic losses to grapevine ( Vitis vinifera ) production. To date, the application of fungicides is the most efficient method to control the pathogen and the implementation of novel and sustainable disease control methods is a major challenge. RNA interference (RNAi) represents a novel biotechnological tool with a great potential for controlling fungal pathogens. Recently, a candidate susceptibility gene ( VviLBDIf7 ) to downy mildew has been identified in V. vinifera . In this work, the efficacy of RNAi triggered by exogenous double-stranded RNA (dsRNA) in controlling P. viticola infections has been assessed in a highly susceptible grapevine cultivar (Pinot noir) by knocking down VviLBDIf7 gene. The effects of dsRNA treatment on this target gene were assessed by evaluating gene expression, disease severity, and development of vegetative and reproductive structures of P. viticola in the leaf tissues. Furthermore, the effects of dsRNA treatment on off-target ( EF1α , GAPDH , PEPC , and PEPCK ) and jasmonic acid metabolism ( COI1 ) genes have been evaluated. Exogenous application of dsRNA led to significant reductions both in VviLBDIf7 gene expression, 5 days after the treatment, and in the disease severity when artificial inoculation was carried out 7 days after dsRNA treatments. The pathogen showed clear alterations to both vegetative (hyphae and haustoria) and reproductive structures (sporangiophores) that resulted in stunted growth and reduced sporulation. Treatment with dsRNA showed signatures of systemic activity and no deleterious off-target effects. These results demonstrated the potential of RNAi for silencing susceptibility factors in grapevine as a sustainable strategy for pathogen control, underlying the possibility to adopt this promising biotechnological tool in disease management strategies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Marcianò, Ricciardi, Marone Fassolo, Passera, Bianco, Failla, Casati, Maddalena, De Lorenzis and Toffolatti.) more...
- Published
- 2021
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18. From plant resistance response to the discovery of antimicrobial compounds: The role of volatile organic compounds (VOCs) in grapevine downy mildew infection.
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Ricciardi V, Marcianò D, Sargolzaei M, Maddalena G, Maghradze D, Tirelli A, Casati P, Bianco PA, Failla O, Fracassetti D, Toffolatti SL, and De Lorenzis G
- Subjects
- Fungicides, Industrial chemistry, Gene Expression Regulation, Plant, Vitis microbiology, Disease Resistance, Oomycetes pathogenicity, Plant Diseases microbiology, Vitis chemistry, Volatile Organic Compounds chemistry
- Abstract
The discovery of new mechanisms of resistance and natural bioactive molecules could be two of the possible ways to reduce fungicide use in vineyard and assure an acceptable and sustainable protection against Plasmopara viticola, the grapevine downy mildew agent. Emission of volatile organic compounds (VOCs), such as terpenes, norisoprenoids, alcohols and aldehydes, is frequently induced in plants in response to attack by pathogens, such as P. viticola, that is known to cause a VOCs increment in cultivars harboring American resistance traits. In this study, the role of leaf VOCs in the resistance mechanism of two resistant cultivars (Mgaloblishvili, a pure Vitis vinifera cultivar, and Bianca, an interspecific hybrid) and the direct antimicrobial activity of four selected VOCs have been investigated. The leaf VOCs profiles, analyzed through solid-phase microextraction gas chromatography-mass spectrometry analysis, as well as the expression of six terpene synthases (TPSs), were determined upon pathogen inoculation. In both cultivars, the expression pattern of six TPSs increased soon after pathogen inoculation and an increment of nine VOCs has been detected. While in Mgaloblishvili VOCs were synthesized early after P. viticola inoculation, they constituted a late response to pathogen in Bianca. All the four terpenes (farnesene, nerolidol, ocimene and valencene), chosen according to the VOC profiles and gene expression analysis, caused a significant reduction (53-100%) in P. viticola sporulation. These results support the role of VOCs into defense mechanisms of both cultivars and suggest their potential role as a natural and eco-friendly solution to protect grapevine from P. viticola., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.) more...
- Published
- 2021
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19. Georgian Grapevine Cultivars: Ancient Biodiversity for Future Viticulture.
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Sargolzaei M, Rustioni L, Cola G, Ricciardi V, Bianco PA, Maghradze D, Failla O, Quaglino F, Toffolatti SL, and De Lorenzis G
- Abstract
Grapevine ( Vitis vinifera ) is one of the most widely cultivated plant species of agricultural interest, and is extensively appreciated for its fruits and the wines made from its fruits. Considering the high socio-economic impact of the wine sector all over the world, in recent years, there has been an increase in work aiming to investigate the biodiversity of grapevine germplasm available for breeding programs. Various studies have shed light on the genetic diversity characterizing the germplasm from the cradle of V. vinifera domestication in Georgia (South Caucasus). Georgian germplasm is placed in a distinct cluster from the European one and possesses a rich diversity for many different traits, including eno-carpological and phenological traits; resistance to pathogens, such as oomycetes and phytoplasmas; resistance to abiotic stresses, such as sunburn. The aim of this review is to assess the potential of Georgian cultivars as a source of useful traits for breeding programs. The unique genetic and phenotypic aspects of Georgian germplasm were unraveled, to better understand the diversity and quality of the genetic resources available to viticulturists, as valuable resources for the coming climate change scenario., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Sargolzaei, Rustioni, Cola, Ricciardi, Bianco, Maghradze, Failla, Quaglino, Toffolatti and De Lorenzis.) more...
- Published
- 2021
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20. Multilocus Genotyping Reveals New Molecular Markers for Differentiating Distinct Genetic Lineages among " Candidatus Phytoplasma Solani" Strains Associated with Grapevine Bois Noir.
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Passera A, Zhao Y, Murolo S, Pierro R, Arsov E, Mori N, Moussa A, Silletti MR, Casati P, Panattoni A, Wei W, Mitrev S, Materazzi A, Luvisi A, Romanazzi G, Bianco PA, Davis RE, and Quaglino F
- Abstract
Grapevine Bois noir (BN) is associated with infection by " Candidatus Phytoplasma solani" (CaPsol). In this study, an array of CaPsol strains was identified from 142 symptomatic grapevines in vineyards of northern, central, and southern Italy and North Macedonia. Molecular typing of the CaPsol strains was carried out by analysis of genes encoding 16S rRNA and translation elongation factor EF-Tu, as well as eight other previously uncharacterized genomic fragments. Strains of tuf -type a and b were found to be differentially distributed in the examined geographic regions in correlation with the prevalence of nettle and bindweed. Two sequence variants were identified in each of the four genomic segments harboring hlyC , cbiQ - glyA , trxA - truB - rsuA , and rplS - tyrS - csdB , respectively. Fifteen CaPsol lineages were identified based on distinct combinations of sequence variations within these genetic loci. Each CaPsol lineage exhibited a unique collective restriction fragment length polymorphism (RFLP) pattern and differed from each other in geographic distribution, probably in relation to the diverse ecological complexity of vineyards and their surroundings. This RFLP-based typing method could be a useful tool for investigating the ecology of CaPsol and the epidemiology of its associated diseases. Phylogenetic analyses highlighted that the sequence variants of the gene hlyC , which encodes a hemolysin III-like protein, separated into two clusters consistent with the separation of two distinct lineages on the basis of tufB gene sequences. Alignments of deduced full protein sequences of elongation factor-Tu ( tufB gene) and hemolysin III-like protein ( hlyC gene) revealed the presence of critical amino acid substitutions distinguishing CaPsol strains of tuf -type a and b. Findings from the present study provide new insights into the genetic diversity and ecology of CaPsol populations in vineyards. more...
- Published
- 2020
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21. Bacterial microbiota associated with insect vectors of grapevine Bois noir disease in relation to phytoplasma infection.
- Author
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Moussa A, Passera A, Sanna F, Faccincani M, Casati P, Bianco PA, Mori N, and Quaglino F
- Subjects
- Insect Vectors, Phylogeny, Phytoplasma Disease, Plant Diseases, Microbiota, Vitis
- Abstract
Bois noir is a grapevine disease causing severe yield loss in vineyards worldwide. It is associated with 'Candidatus Phytoplasma solani', a phloem-limited bacterium transmitted by polyphagous insects. Due to its complex epidemiology, it is difficult to organize effective containment measures. This study aimed to describe the bacterial microbiota associated with 'Candidatus Phytoplasma solani' infected and non-infected insect hosts and vectors to investigate if phytoplasma presence can shape the microbiota. Alpha-diversity analysis showed a low microbiota diversity in these insects, in which few genera were highly abundant. Beta-diversity analysis revealed that the xylem- and phloem-feeding behavior influences the microbiota structure. Moreover, it highlighted that phytoplasma infection is associated with a restructuring of microbiota exclusively in Deltocephalinae insect vectors. Obtained data showed that 'Candidatus Phytoplasma solani' may have adverse effects on the endosymbionts Sulcia and Wolbachia, suggesting a possible fitness modification in the insects. The phytoplasma-antagonistic Dyella was not found in any of the examined insect species. The results indicate an interesting perspective regarding the microbial signatures associated with xylem- and phloem-feeding insects, and determinants that could be relevant to establish whether an insect species can be a vector or not, opening up new avenues for developing microbial resource management-based approaches., (© The Author(s) 2020. Published by Oxford University Press on behalf of FEMS.) more...
- Published
- 2020
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22. Rpv29 , Rpv30 and Rpv31 : Three Novel Genomic Loci Associated With Resistance to Plasmopara viticola in Vitis vinifera .
- Author
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Sargolzaei M, Maddalena G, Bitsadze N, Maghradze D, Bianco PA, Failla O, Toffolatti SL, and De Lorenzis G
- Abstract
Plasmopara viticola (Berk. et Curt.) Berl. and de Toni, the agent of downy mildew, is one of the most important pathogens of European grapevine ( Vitis vinifera L.). Extensive evaluation of cultivated grapevine germplasm has highlighted the existence of resistant phenotypes in the Georgian (Southern Caucasus) germplasm. Resistance is shown as a reduction in disease severity. Unraveling the genetic architecture of grapevine response to P. viticola infection is crucial to develop resistant varieties and reduce the impact of disease management. The aim of this work was to apply a genome-wide association (GWA) approach to a panel of Georgian-derived accessions phenotyped for P. viticola susceptibility and genotyped with Vitis18kSNP chip array. GWA identified three highly significant novel loci on chromosomes 14 ( Rpv29 ), 3 ( Rpv30 ) and 16 ( Rpv31 ) associated with a low level of pathogen sporulation. Rpv29 , Rpv30 , and Rpv31 loci appeared to be associated with plant defense genes against biotic stresses, such as genes involved in pathogen recognition and signal transduction. This study provides the first evidence of resistant loci against P. viticola in V. vinifera germplasm, and identifies potential target genes for breeding P. viticola resistant grapevine cultivars., (Copyright © 2020 Sargolzaei, Maddalena, Bitsadze, Maghradze, Bianco, Failla, Toffolatti and De Lorenzis.) more...
- Published
- 2020
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23. Characterization of fungicide sensitivity profiles of Botrytis cinerea populations sampled in Lombardy (Northern Italy) and implications for resistance management.
- Author
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Toffolatti SL, Russo G, Bezza D, Bianco PA, Massi F, Marcianò D, and Maddalena G
- Subjects
- Drug Resistance, Fungal, Italy, Plant Diseases, Botrytis, Fungicides, Industrial
- Abstract
Background: Resistance to fungicides is one of the aspects that must be considered when planning treatments to achieve an optimal control of grey mold, caused by Botrytis cinerea, in vineyards. In this study, extensive fungicide resistance monitoring was carried out in Northern Italy (Lombardy region) to evaluate several aspects of fungicide resistance (frequency of resistance, effect of field treatments, mechanism of resistance and fitness) on 720 B. cinerea strains isolated from 36 vineyards., Results: Of the characterized strains, 12% were resistant to a single fungicide class (3% to the succinate dehydrogenase inhibitor boscalid, 4% to the anilinopirimidine cyprodinil; 5% to the phenylpirrole fludioxonil; 0.1% to the ketoreductase inhibitor fenhexamid) and 0.8% to two fungicide classes contemporaneously. Resistance was associated with mutations reported in the literature for boscalid (H272Y/R) and fenhexamid (P238S or I232M). Two new mutations in sdhC (A187F) and in sdhD (I189L) could be related to boscalid resistance. Strains resistant to fludioxonil did not show any known mutations. No significant differences were found in the fitness of sensitive and resistant strains., Conclusion: Overall, field populations of B. cinerea showed a relatively low frequency of resistance, but the geographical distribution of resistance, genetic mechanisms of resistance and fitness of resistant strains suggest that management of resistance should be implemented, at local and regional levels. Particular attention should be given to the fungicide sprays planned before veraison, since they seem to be associated with a higher frequency of resistant strains in vineyards. © 2020 Society of Chemical Industry., (© 2020 Society of Chemical Industry.) more...
- Published
- 2020
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24. Proposal of A New Bois Noir Epidemiological Pattern Related to ' Candidatus Phytoplasma Solani' Strains Characterized by A Possible Moderate Virulence in Tuscany.
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Pierro R, Panattoni A, Passera A, Materazzi A, Luvisi A, Loni A, Ginanni M, Lucchi A, Bianco PA, and Quaglino F
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Bois noir (BN), associated with ' Candidatus Phytoplasma solani' (CaPsol), is the most widespread disease of the grapevine yellows complex worldwide. In this work, BN epidemiology was investigated in a case study vineyard where an unusual CaPsol strain, previously detected only in other host plants, was found to be prevalent in grapevine. Experimental activities included: symptom observation; sampling of symptomatic vines, Auchenorrhyncha specimens, and weeds; molecular detection and typing of CaPsol strains; statistical analyses for determining possible relationships between CaPsol relative concentration, strain type, and symptom severity. Among insects, Reptalus quinquecostatus was the most abundant and was found to be highly infected by CaPsol, while Hyalesthes obsoletus , the main CaPsol vector, was not caught. Moreover, R. quinquecostatus harbored CaPsol strains carrying uniquely the stamp sequence variant St10, also identified as prevalent in vines and in the majority of weeds, and all the secY variants identified in the vineyard. Statistical analyses revealed that CaPsol strains carrying the St10 variant are not associated with severe symptoms, suggesting their possible moderate virulence. Based on such evidence, a new BN epidemiological pattern related to these CaPsol strains and involving grapevine, R. quinquecostatus , and/or weeds is proposed. Furthermore, the possible presence of other players (vectors and weeds) involved in CaPsol transmission to grapevines was highlighted., Competing Interests: The authors declare no conflict of interest. more...
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- 2020
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25. Novel Aspects on The Interaction Between Grapevine and Plasmopara viticola : Dual-RNA-Seq Analysis Highlights Gene Expression Dynamics in The Pathogen and The Plant During The Battle For Infection.
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Toffolatti SL, De Lorenzis G, Brilli M, Moser M, Shariati V, Tavakol E, Maddalena G, Passera A, Casati P, Pindo M, Cestaro A, Maghradze D, Failla O, Bianco PA, and Quaglino F
- Subjects
- Gene Expression Regulation, Plant genetics, Host-Pathogen Interactions genetics, Oomycetes genetics, Oomycetes pathogenicity, Plant Diseases microbiology, Plant Leaves genetics, Plant Leaves growth & development, Plant Leaves microbiology, Sequence Analysis, RNA, Vitis growth & development, Vitis microbiology, Disease Resistance genetics, Plant Diseases genetics, Transcriptome genetics, Vitis genetics
- Abstract
Mgaloblishvili, a Vitis vinifera cultivar, exhibits unique resistance traits against Plasmopara viticola , the downy mildew agent. This offers the unique opportunity of exploring the molecular responses in compatible and incompatible plant-pathogen interaction. In this study, whole transcriptomes of Mgaloblishvili, Pinot noir (a V. vinifera susceptible cultivar), and Bianca (a resistant hybrid) leaves, inoculated and non-inoculated with the pathogen , were used to identify P. viticola effector-encoding genes and plant susceptibility/resistance genes. Multiple effector-encoding genes were identified in P. viticola transcriptome, with remarkable expression differences in relation to the inoculated grapevine cultivar. Intriguingly, five apoplastic effectors specifically associated with resistance in V. vinifera . Gene coexpression network analysis identified specific modules and metabolic changes occurring during infection in the three grapevine cultivars. Analysis of these data allowed, for the first time, the detection in V. vinifera of a putative P. viticola susceptibility gene, encoding a LOB domain-containing protein. Finally, the de novo assembly of Mgaloblishvili, Pinot noir, and Bianca transcriptomes and their comparison highlighted novel candidate genes that might be at the basis of the resistant phenotype. These results open the way to functional analysis studies and to new perspectives in molecular breeding of grapevine for resistance to P. viticola ., Competing Interests: The authors declare no conflict of interest. more...
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- 2020
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26. Identification and ecology of alternative insect vectors of 'Candidatus Phytoplasma solani' to grapevine.
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Quaglino F, Sanna F, Moussa A, Faccincani M, Passera A, Casati P, Bianco PA, and Mori N
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- Animals, Ecosystem, Insect Vectors genetics, Phylogeny, Phytoplasma genetics, Plant Diseases microbiology, Sequence Analysis, DNA, Insect Vectors physiology, Phytoplasma physiology, Vitis microbiology
- Abstract
Bois noir, a disease of the grapevine yellows complex, is associated with 'Candidatus Phytoplasma solani' and transmitted to grapevines in open fields by the cixiids Hyalesthes obsoletus and Reptalus panzeri. In vine-growing areas where the population density of these vectors is low within the vineyard, the occurrence of bois noir implies the existence of alternative vectors. The aim of this study was to identify alternative vectors through screening of the Auchenorrhyncha community, phytoplasma typing by stamp gene sequence analyses, and transmission trials. During field activities, conducted in Northern Italy in a vineyard where the bois noir incidence was extremely high, nine potential alternative insect vectors were identified according to high abundance in the vineyard agro-ecosystem, high infection rate, and harbouring phytoplasma strains characterized by stamp gene sequence variants found also in symptomatic grapevines. Transmission trials coupled with molecular analyses showed that at least eight species (Aphrodes makarovi, Dicranotropis hamata, Dictyophara europaea, Euscelis incisus, Euscelidius variegatus, Laodelphax striatella, Philaenus spumarius, and Psammotettix alienus/confinis) are alternative vectors of 'Candidatus Phytoplasma solani' to grapevines. These novel findings highlight that bois noir epidemiology in vineyard agro-ecosystems is more complex than previously known, opening up new perspectives in the disease management. more...
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- 2019
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27. A time-course investigation of resistance to the carboxylic acid amide mandipropamid in field populations of Plasmopara viticola treated with anti-resistance strategies.
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Toffolatti SL, Russo G, Campia P, Bianco PA, Borsa P, Coatti M, Torriani SF, and Sierotzki H
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- Oomycetes physiology, Plant Diseases microbiology, Time Factors, Vitis growth & development, Vitis microbiology, Amides pharmacology, Carboxylic Acids pharmacology, Drug Resistance, Fungal drug effects, Oomycetes drug effects
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Background: Despite anti-resistance strategies being recommended to reduce selection pressure on insensitive strains, no information is available on fungal population dynamics following their application in real field conditions. In this study, the effects on Plasmopara viticola populations of two identical spray programs, differing only in including or not the carboxylic acid amide (CAA) mandipropamid in mixture and in alternation with an anti-resistance partner, were compared in terms of downy mildew control efficacy and mandipropamid sensitivity in two commercial vineyards for four seasons., Results: Both programs effectively and similarly protected grapevine from downy mildew, despite different starting sensitivity levels of the P. viticola populations. In the vineyard where resistant strains were initially present, the frequency of mutations associated with resistance (G1105S/V) fluctuated within seasons in both programs and a shift towards sensitivity occurred after 3 years of the mandipropamid-free program. Where sensitivity was initially present, no changes occurred in the mandipropamid-free program and resistant strains were selected in the mandipropamid program in high disease pressure conditions., Conclusion: The anti-resistance strategy including mandipropamid in mixture showed a good field performance, but did not completely prevent an increase in the frequency of insensitive strains. This supports the need for appropriate planning to determine which mixtures should be used in the field. © 2018 Society of Chemical Industry., (© 2018 Society of Chemical Industry.) more...
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- 2018
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28. Unique resistance traits against downy mildew from the center of origin of grapevine (Vitis vinifera).
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Toffolatti SL, De Lorenzis G, Costa A, Maddalena G, Passera A, Bonza MC, Pindo M, Stefani E, Cestaro A, Casati P, Failla O, Bianco PA, Maghradze D, and Quaglino F
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- Ethylenes metabolism, Gene Expression Profiling, Gene Expression Regulation, Plant, Host-Pathogen Interactions, Microscopy, Confocal, Peronospora pathogenicity, Quantitative Trait Loci, Signal Transduction, Up-Regulation, Vitis classification, Vitis genetics, Vitis microbiology, Disease Resistance, Peronospora growth & development, Plant Proteins genetics, Vitis growth & development
- Abstract
The Eurasian grapevine (Vitis vinifera), an Old World species now cultivated worldwide for high-quality wine production, is extremely susceptible to the agent of downy mildew, Plasmopara viticola. The cultivation of resistant V. vinifera varieties would be a sustainable way to reduce the damage caused by the pathogen and the impact of disease management, which involves the economic, health and environmental costs of frequent fungicide application. We report the finding of unique downy mildew resistance traits in a winemaking cultivar from the domestication center of V. vinifera, and characterize the expression of a range of genes associated with the resistance mechanism. Based on comparative experimental inoculations, confocal microscopy and transcriptomics analyses, our study shows that V. vinifera cv. Mgaloblishvili, native to Georgia (South Caucasus), exhibits unique resistance traits against P. viticola. Its defense response, leading to a limitation of P. viticola growth and sporulation, is determined by the overexpression of genes related to pathogen recognition, the ethylene signaling pathway, synthesis of antimicrobial compounds and enzymes, and the development of structural barriers. The unique resistant traits found in Mgaloblishvili highlight the presence of a rare defense system in V. vinifera against P. viticola which promises fresh opportunities for grapevine genetic improvement. more...
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- 2018
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29. Studies of Microbiota Dynamics Reveals Association of " Candidatus Liberibacter Asiaticus" Infection with Citrus ( Citrus sinensis ) Decline in South of Iran.
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Passera A, Alizadeh H, Azadvar M, Quaglino F, Alizadeh A, Casati P, and Bianco PA
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- Iran, Phytoplasma genetics, Plant Leaves microbiology, Plant Roots microbiology, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Citrus sinensis microbiology, DNA, Bacterial genetics, Microbiota genetics, Plant Diseases microbiology, Rhizobiaceae genetics
- Abstract
Citrus Decline Disease was recently reported to affect several citrus species in Iran when grafted on a local rootstock variety, Bakraee. Preliminary studies found “ Candidatus Phytoplasma aurantifoliae” and “ Candidatus Liberibacter asiaticus” as putative etiological agents, but were not ultimately able to determine which one, or if an association of both, were causing the disease. The current study has the aim of characterizing the microbiota of citrus plants that are either asymptomatic, showing early symptoms, or showing late symptoms through amplification of the V1–V3 region of 16S rRNA gene using an Illumina sequencer in order to (i) clarify the etiology of the disease, and (ii) describe the microbiota associated to different symptom stages. Our results suggest that liberibacter may be the main pathogen causing Citrus Decline Disease, but cannot rule out the possibility of phytoplasma being involved as well. The characterization of microbiota shows that the leaves show only two kinds of communities, either symptomatic or asymptomatic, while roots show clear distinction between early and late symptoms. These results could lead to the identification of bacteria that are related to successful plant defense response and, therefore, to immunity to the Citrus Decline Disease. more...
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- 2018
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30. Molecular Typing of Bois Noir Phytoplasma Strains in the Chianti Classico Area (Tuscany, Central Italy) and Their Association with Symptom Severity in Vitis vinifera 'Sangiovese'.
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Pierro R, Passera A, Panattoni A, Casati P, Luvisi A, Rizzo D, Bianco PA, Quaglino F, and Materazzi A
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- DNA, Bacterial genetics, DNA, Bacterial metabolism, Italy, Molecular Typing, Phylogeny, Phytoplasma genetics, Phytoplasma classification, Plant Diseases microbiology, Vitis microbiology
- Abstract
Bois noir (BN) is the most widespread disease of the grapevine yellows complex in the Euro-Mediterranean area. BN is caused by 'Candidatus Phytoplasma solani' (BNp), transmitted from herbaceous plants to grapevine by polyphagous insect vectors. In this study, genetic diversity among BNp strains and their prevalence and possible association with grapevine symptom severity were investigated in a Sangiovese clone organic vineyard in the Chianti Classico area (Tuscany). Field surveys over 2 years revealed a range of symptom severity on grapevine and an increase of BN incidence. A TaqMan allelic discrimination assay detected only tufB type b among BNp strains, suggesting the prevalence of the bindweed-related ecology. Nucleotide sequence analyses of vmp1 and stamp genes identified 12 vmp1 and 16 stamp sequence variants, showing an overall positive selection for such genes. The prevalent genotype was Vm43/St10, reported for the first time in this study and closely related to strains identified only in the French Eastern Pyrenees. BNp strains identified in the examined vineyard and mostly grouped in separate bindweed-related phylogenetic clusters showed statistically significant differences in their distribution in grapevines exhibiting distinct symptom severity. These results suggest the possible occurrence of a range of virulence within BNp strain populations in the Chianti Classico area. more...
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- 2018
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31. Competition assays revealed Paenibacillus pasadenensis strain R16 as a novel antifungal agent.
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Passera A, Venturini G, Battelli G, Casati P, Penaca F, Quaglino F, and Bianco PA
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- Antifungal Agents metabolism, Cluster Analysis, DNA, Bacterial chemistry, DNA, Bacterial genetics, DNA, Ribosomal chemistry, DNA, Ribosomal genetics, DNA-Directed RNA Polymerases genetics, Farnesol metabolism, Paenibacillus growth & development, Phylogeny, Plant Diseases microbiology, Plant Diseases prevention & control, Plant Growth Regulators metabolism, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Antibiosis, Ascomycota growth & development, Paenibacillus physiology
- Abstract
The development of new sustainable containment strategies of plant diseases is very important to guarantee food security while reducing the environmental impact of agriculture. Research of new biocontrol agents is a long and difficult process that involves several steps that start from the identification of possible candidates which, for example, show antibiotic activities, and ends with in field, large scale trials. In this study, the plant growth promoting potential and antifungal effect exerted by a novel, putative candidate biocontrol agent, strain R16, identified as Paenibacillus pasadenensis by sequence analysis of 16S rRNA and rpoB genes, against three important plant pathogenic fungi (Botrytis cinerea, Fusarium verticillioides, and Phomopsis viticola), were assessed. Biochemical assays to determine plant growth promoting potential gave negative results for siderophore production and phosphate solubilization, and positive results for ACC-deamination and IAA production. Further biochemical assays for endophytic lifestyle and antifungal activity gave positive results for catalase and chitinase activity, respectively. In vitro antagonism assays showed that strain R16 is effective against B. cinerea, reducing mycelial growth both in dual-culture and through volatile substances, characterized to be mostly composed by farnesol, and inhibiting conidia germination. Good antagonistic potential was also observed in vitro towards P. viticola, but not towards F. verticillioides. Moreover, in vivo assays confirmed the strain R16 activity reduced the infection rate on B. cinerea-inoculated berries. The obtained results firstly proved that P. pasadenesis strain R16 is a putative plant growth promoter and effective against phytopathogenic fungi. Further studies will be needed to investigate the possible application of this strain as a biocontrol agent., (Copyright © 2017 Elsevier GmbH. All rights reserved.) more...
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- 2017
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32. Identification and Characterization of New 'Candidatus Phytoplasma solani' Strains Associated with Bois Noir Disease in Vitis vinifera L. Cultivars Showing a Range of Symptom Severity in Georgia, the Caucasus Region.
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Quaglino F, Maghradze D, Casati P, Chkhaidze N, Lobjanidze M, Ravasio A, Passera A, Venturini G, Failla O, and Bianco PA
- Abstract
Evidence from a preliminary survey highlighted that 'Candidatus Phytoplasma solani', the etiological agent of bois noir (BN) disease of grapevine, infects grapevine varieties in Georgia, a country of the South Caucasus. In this study, field surveys were carried out to investigate the BN symptom severity in international and Georgian native varieties. 'Ca. P. solani' was detected and identified by polymerase chain reaction-based amplification and restriction fragment length polymorphism analysis of 16S ribosomal DNA, and further characterized by multiple gene typing analysis (vmp1 and stamp genes). Obtained data highlighted that the majority of Georgian grapevine varieties showed moderate and mild symptoms, whereas international cultivars exhibited severe symptoms. Molecular characterization of 'Ca. P. solani' from grapevine revealed the presence of 11 distinct phytoplasma types. Only one type (VmGe12/StGe7) was identical to a strain previously reported in periwinkle from Lebanon; the other 'Ca. P. solani' types are described here for the first time. Phylogenetic analyses of vmp1 and stamp gene concatenated nucleotide sequences showed that 'Ca. P. solani' strains in Georgia are associated mainly with the bindweed-related BN host system. Moreover, the fact that 'Ca. P. solani' strains are distributed in grapevine cultivars showing a range of symptom intensity suggests a different susceptibility of such local cultivars to BN. more...
- Published
- 2016
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33. 'Candidatus Phytoplasma phoenicium' associated with almond witches'-broom disease: from draft genome to genetic diversity among strain populations.
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Quaglino F, Kube M, Jawhari M, Abou-Jawdah Y, Siewert C, Choueiri E, Sobh H, Casati P, Tedeschi R, Lova MM, Alma A, and Bianco PA
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- Acholeplasmataceae, Bacterial Proteins genetics, Cluster Analysis, DNA, Bacterial chemistry, DNA, Bacterial genetics, DNA, Ribosomal chemistry, DNA, Ribosomal genetics, Genotype, Lebanon, Molecular Sequence Data, Molecular Typing, Phylogeny, Prunus persica microbiology, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Genetic Variation, Genome, Bacterial, Phytoplasma classification, Phytoplasma isolation & purification, Plant Diseases microbiology, Prunus dulcis microbiology
- Abstract
Background: Almond witches'-broom (AlmWB), a devastating disease of almond, peach and nectarine in Lebanon, is associated with 'Candidatus Phytoplasma phoenicium'. In the present study, we generated a draft genome sequence of 'Ca. P. phoenicium' strain SA213, representative of phytoplasma strain populations from different host plants, and determined the genetic diversity among phytoplasma strain populations by phylogenetic analyses of 16S rRNA, groEL, tufB and inmp gene sequences., Results: Sequence-based typing and phylogenetic analysis of the gene inmp, coding an integral membrane protein, distinguished AlmWB-associated phytoplasma strains originating from diverse host plants, whereas their 16S rRNA, tufB and groEL genes shared 100 % sequence identity. Moreover, dN/dS analysis indicated positive selection acting on inmp gene. Additionally, the analysis of 'Ca. P. phoenicium' draft genome revealed the presence of integral membrane proteins and effector-like proteins and potential candidates for interaction with hosts. One of the integral membrane proteins was predicted as BI-1, an inhibitor of apoptosis-promoting Bax factor. Bioinformatics analyses revealed the presence of putative BI-1 in draft and complete genomes of other 'Ca. Phytoplasma' species., Conclusion: The genetic diversity within 'Ca. P. phoenicium' strain populations in Lebanon suggested that AlmWB disease could be associated with phytoplasma strains derived from the adaptation of an original strain to diverse hosts. Moreover, the identification of a putative inhibitor of apoptosis-promoting Bax factor (BI-1) in 'Ca. P. phoenicium' draft genome and within genomes of other 'Ca. Phytoplasma' species suggested its potential role as a phytoplasma fitness-increasing factor by modification of the host-defense response. more...
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- 2015
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34. First Report of Grapevine virus A and Grapevine fleck virus in the Former Yugoslav Republic of Macedonia.
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Kostadinovska E, Mitrev S, Bianco PA, Casati P, and Bulgari D
- Abstract
Grapevine (Vitis vinifera L.) is an economically important crop and can host several different viruses, including those that have to be excluded from certified propagating material in Europe. Among these, the Vitivirus Grapevine virus A (GVA) and the Maculavirus Grapevine fleck virus (GFkV) are phloem-limited viruses that are associated with two different grapevine diseases, Kober stem grooving, belonging to the rugose wood complex, and fleck diseases, respectively. During a survey conducted in 2012 in the former Republic of Macedonia, symptomatic plants with reddening of leaves were collected for laboratory analyses. In this study, grapevine red varieties (Vranec, Francovka, and Pinot noir) from four different localities (Stip, Kavadarci, Valandovo, and Gevgelija) in Macedonia were examined. Thirty-four samples were analyzed by DAS-ELISA using commercially antibodies against Grapevine leafroll associated virus-3 (GLRaV-3). Ten selected samples were processed through DAS-ELISA and molecular assays also for the presence of GVA and GFkV. Total RNA was extracted as previously described (2) and retro-transcribed (RT) using random primers followed by PCR assay with primers GVA-MP (5'-GCCAGAGGTGTTTGAGACAAT-3') and GVA-CPdt (5'-TTTTGTCTTCGTGTGACAACCT-3') (1), which amplified a GVA-specific fragment of 986 bp, and with primers GFkV-U279 (5'-TGGTCCTCGGCCCAGTGAAAAAGTA-3') and GFkV-L630 (5'-GGCCAGGTTGTAGTCGGTGTTGTC-3') (3), which amplified a GFkV-specific region of 315 bp. Results from DAS-ELISA test showed the presence of GLRaV-3 in 21 tested samples and of GVA and GFkV in six and three out of 10 selected samples, respectively. GVA was found in Vranec and Francovka vines sampled in all the locations mentioned before, while GFkV was detected in Vranec and Pinot noir vines, in Stip, Kavadarci, and Gevgelija. These latter results were confirmed by RT-PCR assays; then, four GVA-specific and three GFkV-specific amplicons were sequenced from both directions to get a 3× coverage. For GVA fragment, a primer pair designed in the internal part of the sequence was also used. BLASTn analyses showed that (i) PCR products amplified with GVA-specific primers shared best nucleotide sequence identities, ranging from 91.7 to 93.7%, with GVA isolate at GenBank Accession No. X75433; (ii) PCR products amplified with GFkV-specific primers shared best nucleotide sequence identities, from 92.5 to 94.7%, with GFkV isolate at AJ309022. These evidences reinforced the serological and PCR results indicating that GVA and GFkV were identified in examined grapevine plants in this study. Nucleotide sequences of GVA (KF594432 to 35) and GFkV (KF594429 to 31) were submitted to GenBank. To our knowledge, this is the first report of GVA and GFkV grapevine viruses in the Former Yugoslav Republic of Macedonia. References: (1) J. De Meyer et al. Page 138 in: Extended Abstracts, 13th Meeting of ICVG, Adelaide, 12-17 March 2000. (2) D. J. MacKenzie et al. Plant Dis. 81:222, 1997. (3) B. J. Shi et al. Ann. Appl. Biol. 142:349, 2003. more...
- Published
- 2014
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35. First Report of 'Candidatus Phytoplasma solani' and 'Ca. P. convolvuli' Associated with Grapevine Bois Noir and Bindweed Yellows, Respectively, in Georgia.
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Quaglino F, Maghradze D, Chkhaidze N, Casati P, Failla O, and Bianco PA
- Abstract
A survey carried out in Georgian vineyards, located in the Khaketi region, in September 2013, showed the presence of vines of the cultivar Chardonnay with typical grapevine yellows (GY) symptoms including leaf discoloration and curling, berry shriveling, and irregular maturation of wood. In the same vineyards, bindweed (Convolvulus arvensis L.) plants showing shoot proliferation and leaf yellowing were found, suggesting the involvement of phytoplasmas in the disease etiology. Total DNA was extracted by a CTAB method from leaf veins of 18 symptomatic and two asymptomatic grapevines, and from four symptomatic and two asymptomatic bindweeds, and analyzed by PCR assays. Moreover, DNA extracted from 'Candidatus Phytoplasma asteris' strain SAY (group 16SrI), 'Ca. P. solani' strain STOL (group 16SrXII), and 'Ca. P. ulmi' strain EY1 (group 16SrV) were used as positive controls. DNA extracted from healthy periwinkle and a reaction mixture without template were employed as negative controls. Nested PCRs targeting the 16S rDNA, carried out using the primer pairs P1/P7 followed by R16F2n/R16R2 (1), produced a band of the expected size (1,250 nt) in all the symptomatic grapevine and bindweed plants, and in the positive controls. No amplification was observed with DNA from asymptomatic plants nor the negative controls. PCR products were sequenced by a commercial sequencing service (Primm, Milan, Italy). The 16S rDNA nucleotide sequences of phytoplasmas identified in all grapevines and in two bindweed samples shared >99.5% sequence identity with 'Ca. P. solani' reference strain STOL (GenBank Accession No. AF248959), and carried identical STOL-unique signature sequence and distinguishing sequence blocks (3). Moreover, nucleotide sequences of phytoplasmas identified in the other two bindweed samples shared >99.6% sequence identity with 'Ca. P. convolvuli' reference strain BY-S57/11 (JN833705) (2). RFLP and phylogenetic analyses confirmed the affiliation of the phytoplasma strains identified in grapevine and bindweed plants in Georgia to the species 'Ca. P. solani' (subgroup 16SrXII-A) and 'Ca. P. convolvuli' (subgroup 16SrXII-H). Representative 16S rDNA nucleotide sequences were deposited in NCBI GenBank website with accession nos. KF996535 and KF996536 ('Ca. P. solani' from grapevine and bindweed, respectively), and KF996537 ('Ca. P. convolvuli'). Future studies will focus on investigating the spread and impact of 'Ca. P. solani'-associated bois noir (BN) in Georgia. In particular, the identification of 'Ca. P. solani' in bindweeds suggested the presence of the insect Hyalesthes obsoletus, a polyphagous cixiidae responsible for BN phytoplasma transmission in vineyards in Europe. Accurate surveys and molecular analyses will be performed for identifying the insect vector(s) of the BN associated phytoplasma strains in Georgia. Additional studies will be performed to study the spread and impact of 'Ca. P. convolvuli,' identified only in Italy, Germany, Serbia, and Bosnia and Herzegovina (2), throughout the Caucasian countries. References: (1) I.-M. Lee et al. Int. J. Syst. Bacteriol. 48:1153, 1998. (2) M. Martini et al. Int. J. Syst. Evol. Microbiol. 62:2910, 2013. (3) F. Quaglino et al. Int. J. Syst. Evol. Microbiol. 63:2879, 2013. more...
- Published
- 2014
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36. Endophytic bacterial community of grapevine leaves influenced by sampling date and phytoplasma infection process.
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Bulgari D, Casati P, Quaglino F, and Bianco PA
- Subjects
- Italy, Metagenomics, Plant Diseases microbiology, Polymerase Chain Reaction, Seasons, Biota, Endophytes classification, Endophytes isolation & purification, Phytoplasma growth & development, Plant Leaves microbiology, Vitis microbiology
- Abstract
Background: Endophytic bacteria benefit host plant directly or indirectly, e.g. by biocontrol of the pathogens. Up to now, their interactions with the host and with other microorganisms are poorly understood. Consequently, a crucial step for improving the knowledge of those relationships is to determine if pathogens or plant growing season influence endophytic bacterial diversity and dynamic., Results: Four healthy, four phytoplasma diseased and four recovered (symptomatic plants that spontaneously regain a healthy condition) grapevine plants were sampled monthly from June to October 2010 in a vineyard in north-western Italy. Metagenomic DNA was extracted from sterilized leaves and the endophytic bacterial community dynamic and diversity were analyzed by taxon specific real-time PCR, Length-Heterogeneity PCR and genus-specific PCR. These analyses revealed that both sampling date and phytoplasma infection influenced the endophytic bacterial composition. Interestingly, in June, when the plants are symptomless and the pathogen is undetectable (i) the endophytic bacterial community associated with diseased grapevines was different from those in the other sampling dates, when the phytoplasmas are detectable inside samples; (ii) the microbial community associated with recovered plants differs from that living inside healthy and diseased plants. Interestingly, LH-PCR database identified bacteria previously reported as biocontrol agents in the examined grapevines. Of these, Burkholderia, Methylobacterium and Pantoea dynamic was influenced by the phytoplasma infection process and seasonality., Conclusion: Results indicated that endophytic bacterial community composition in grapevine is correlated to both phytoplasma infection and sampling date. For the first time, data underlined that, in diseased plants, the pathogen infection process can decrease the impact of seasonality on community dynamic. Moreover, based on experimental evidences, it was reasonable to hypothesize that after recovery the restructured microbial community could maintain the main structure between seasons. more...
- Published
- 2014
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37. Curtobacterium sp. Genome Sequencing Underlines Plant Growth Promotion-Related Traits.
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Bulgari D, Minio A, Casati P, Quaglino F, Delledonne M, and Bianco PA
- Abstract
Endophytic bacteria are microorganisms residing in plant tissues without causing disease symptoms. Here, we provide the high-quality genome sequence of Curtobacterium sp. strain S6, isolated from grapevine plant. The genome assembly contains 2,759,404 bp in 13 contigs and 2,456 predicted genes., (Copyright © 2014 Bulgari et al.) more...
- Published
- 2014
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38. First Report of 'Candidatus Phytoplasma solani' Strains Associated with Grapevine Bois Noir in Jordan.
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Salem NM, Quaglino F, Abdeen A, Casati P, Bulgari D, Alma A, and Bianco PA
- Abstract
During a survey carried out in Jordanian vineyards in August and October 2012, grapevine (Vitis vinifera L.) plants showing typical grapevine yellows (GY) disease symptoms, including leaf discoloration and curling, berry shriveling, and irregular maturation of wood, were observed. In the same vineyards, bindweed (Convolvulus arvensis L.) plants showing stunting and leaf chromatic alteration were found, suggesting the involvement of phytoplasmas in the disease etiology. Using a CTAB method, total DNA was extracted from leaf veins of 25 symptomatic and two asymptomatic grapevines, and from five symptomatic and two asymptomatic bindweeds for PCR analysis. DNAs from periwinkle (Catharanthus roseus (L.) G. Don) plants infected by 'Ca. Phytoplasma asteris' strain SAY (group 16SrI), 'Ca. Phytoplasma solani' strain STOL (group 16SrXII), and 'Ca. Phytoplasma ulmi' strain EY1 (group 16SrV), were used as positive controls. DNAs from healthy periwinkle and reactions without template DNA were employed as negative controls. 16S rDNA nested PCRs, carried out using the primer pairs P1/P7, followed by R16F2n/R16R2 (1), yielded an amplicon of the expected size (1,250-bp) in three grapevine and in five bindweed samples, and in positive controls. Amplicons were not produced with DNA from 22 symptomatic grapevines (probably because samples were collected late in the growing season and phytoplasma distribution in plants was non-uniform [2]); nor from asymptomatic plants and negative controls. PCR products were sequenced by commercial services in Italy (Primm, Milan) and Korea (Macrogen Inc., Soul). Representative 16S rDNA nucleotide sequences were deposited in NCBI GenBank with accessions KC835139 (from grapevine) and KC835140 (from bindweed). The 16S rDNA nucleotide sequences of phytoplasmas identified in grapevine and bindweed in Jordan shared >99.5% sequence identity with 'Ca. Phytoplasma solani' reference strain STOL (AF248959), and carried identical STOL-unique signature sequences and distinguishing sequence blocks (3). Phylogenetic and in silico RFLP analyses confirmed the affiliation of phytoplasma strains identified in grapevine and bindweed in Jordan to the species 'Ca. Phytoplasma solani' (subgroup 16SrXII-A), opening an avenue to future studies on the dissemination and impact of Bois noir (BN) in Jordan. These studies may add new information about BN, previously reported in neighboring countries (4). Further studies will investigate the role of Hyalesthes obsoletus Signoret, a polyphagous Cixiidae responsible for the BN phytoplasma transmission in Europe, and other possible insect vector(s) in the BN spread in Jordan. References: (1) I.-M. Lee et al. Int. J. Syst. Bact. 48:1153, 1998. (2) F. E. Constable et al. Plant Pathol. 52:267, 2003. (3) F. Quaglino et al. Int. J. Syst. Evol. Microb. 63:2879. (4) E. Choueiri et al. Plant Dis. 86:697, 2002. more...
- Published
- 2013
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39. 'Candidatus Phytoplasma solani', a novel taxon associated with stolbur- and bois noir-related diseases of plants.
- Author
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Quaglino F, Zhao Y, Casati P, Bulgari D, Bianco PA, Wei W, and Davis RE
- Subjects
- Animals, DNA, Bacterial genetics, Genes, Bacterial, Hemiptera microbiology, Italy, Molecular Sequence Data, Phytoplasma genetics, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Phylogeny, Phytoplasma classification, Plant Diseases microbiology, Vitis microbiology
- Abstract
Phytoplasmas classified in group 16SrXII infect a wide range of plants and are transmitted by polyphagous planthoppers of the family Cixiidae. Based on 16S rRNA gene sequence identity and biological properties, group 16SrXII encompasses several species, including 'Candidatus Phytoplasma australiense', 'Candidatus Phytoplasma japonicum' and 'Candidatus Phytoplasma fragariae'. Other group 16SrXII phytoplasma strains are associated with stolbur disease in wild and cultivated herbaceous and woody plants and with bois noir disease in grapevines (Vitis vinifera L.). Such latter strains have been informally proposed to represent a separate species, 'Candidatus Phytoplasma solani', but a formal description of this taxon has not previously been published. In the present work, stolbur disease strain STOL11 (STOL) was distinguished from reference strains of previously described species of the 'Candidatus Phytoplasma' genus based on 16S rRNA gene sequence similarity and a unique signature sequence in the 16S rRNA gene. Other stolbur- and bois noir-associated ('Ca. Phytoplasma solani') strains shared >99 % 16S rRNA gene sequence similarity with strain STOL11 and contained the signature sequence. 'Ca. Phytoplasma solani' is the only phytoplasma known to be transmitted by Hyalesthes obsoletus. Insect vectorship and molecular characteristics are consistent with the concept that diverse 'Ca. Phytoplasma solani' strains share common properties and represent an ecologically distinct gene pool. Phylogenetic analyses of 16S rRNA, tuf, secY and rplV-rpsC gene sequences supported this view and yielded congruent trees in which 'Ca. Phytoplasma solani' strains formed, within the group 16SrXII clade, a monophyletic subclade that was most closely related to, but distinct from, that of 'Ca. Phytoplasma australiense'-related strains. Based on distinct molecular and biological properties, stolbur- and bois noir-associated strains are proposed to represent a novel species level taxon, 'Ca. Phytoplasma solani'; STOL11 is designated the reference strain. more...
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- 2013
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40. Endophytic bacterial community living in roots of healthy and 'Candidatus Phytoplasma mali'-infected apple (Malus domestica, Borkh.) trees.
- Author
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Bulgari D, Bozkurt AI, Casati P, Cağlayan K, Quaglino F, and Bianco PA
- Subjects
- Bacteria genetics, Bacteria isolation & purification, Cluster Analysis, DNA, Bacterial chemistry, DNA, Bacterial genetics, DNA, Ribosomal chemistry, DNA, Ribosomal genetics, Endophytes genetics, Endophytes isolation & purification, Molecular Sequence Data, Phylogeny, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Bacteria classification, Biota, Endophytes classification, Malus microbiology, Plant Diseases microbiology, Plant Roots microbiology
- Abstract
'Candidatus Phytoplasma mali', the causal agent of apple proliferation (AP) disease, is a quarantine pathogen controlled by chemical treatments against insect vectors and eradication of diseased plants. In accordance with the European Community guidelines, novel strategies should be developed for sustainable management of plant diseases by using resistance inducers (e.g. endophytes). A basic point for the success of this approach is the study of endophytic bacteria associated with plants. In the present work, endophytic bacteria living in healthy and 'Ca. Phytoplasma mali'-infected apple trees were described by cultivation-dependent and independent methods. 16S rDNA sequence analysis showed the presence of the groups Proteobacteria, Acidobacteria, Bacteroidetes, Actinobacteria, Chlamydiae, and Firmicutes. In detail, library analyses underscored 24 and 17 operational taxonomic units (OTUs) in healthy and infected roots, respectively, with a dominance of Betaproteobacteria. Moreover, differences in OTUs number and in CFU/g suggested that phytoplasmas could modify the composition of endophytic bacterial communities associated with infected plants. Intriguingly, the combination of culturing methods and cloning analysis allowed the identification of endophytic bacteria (e.g. Bacillus, Pseudomonas, and Burkholderia) that have been reported as biocontrol agents. Future research will investigate the capability of these bacteria to control 'Ca. Phytoplasma mali' in order to develop sustainable approaches for managing AP. more...
- Published
- 2012
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41. Restructuring of endophytic bacterial communities in grapevine yellows-diseased and recovered Vitis vinifera L. plants.
- Author
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Bulgari D, Casati P, Crepaldi P, Daffonchio D, Quaglino F, Brusetti L, and Bianco PA
- Subjects
- Bacteria genetics, Biodiversity, DNA, Bacterial analysis, DNA, Bacterial chemistry, DNA, Bacterial genetics, Microbial Consortia, Molecular Sequence Data, Phylogeny, Polymerase Chain Reaction, Polymorphism, Restriction Fragment Length, RNA, Ribosomal, 16S genetics, Plant Diseases microbiology, Vitis microbiology
- Abstract
Length heterogeneity-PCR assays, combined with statistical analyses, highlighted that the endophytic bacterial community associated with healthy grapevines was characterized by a greater diversity than that present in diseased and recovered plants. The findings suggest that phytoplasmas can restructure the bacterial community by selecting endophytic strains that could elicit a plant defense response. more...
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- 2011
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42. 'Candidatus Liberibacter europaeus' sp. nov. that is associated with and transmitted by the psyllid Cacopsylla pyri apparently behaves as an endophyte rather than a pathogen.
- Author
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Raddadi N, Gonella E, Camerota C, Pizzinat A, Tedeschi R, Crotti E, Mandrioli M, Bianco PA, Daffonchio D, and Alma A
- Subjects
- Animals, DNA, Ribosomal Spacer genetics, Molecular Sequence Data, Phylogeny, Pyrus microbiology, RNA, Bacterial genetics, RNA, Ribosomal, 16S genetics, Rhizobiaceae genetics, Rhizobiaceae growth & development, Sequence Analysis, DNA, Hemiptera microbiology, Plant Diseases microbiology, Rhizobiaceae classification
- Abstract
'Candidatus Liberibacter spp.' cause serious plant diseases. 'Candidatus Liberibacter asiaticus', 'Ca. L. americanus' and 'Ca. L. africanus' are the aetiological agents of citrus greening (Huanglongbing) in Asia, America and Africa. 'Candidatus Liberibacter solanacearum' causes diseases in Solanaceae in America and New Zealand. All four species are vectored by psyllid insects of different genera. Here, we show that the pear psyllid pest Cacopsylla pyri (L.) hosts a novel liberibacter species that we named 'Ca. Liberibacter europaeus'. It can bloom to high titres in the psyllid host, with more than 10(9) 16S rRNA gene copies per individual. Fluorescent in situ hybridization experiments showed that 'Ca. L. europaeus' is present in the host midgut lumen, salivary glands and Malpighian tubules. 'Candidatus L. europaeus' has a relatively high prevalence (> 51%) in C. pyri from different areas in the Piedmont and Valle d'Aosta regions in Italy and can be transmitted to pear plants in experimental transmission trials. However, even though high titres of the bacterium (more than 10(8) 16S rRNA gene copies g(-1) of pear plant tissue) could be detected, in the pear tissues no specific disease symptoms could be observed in the infected plants over a 6-month period. Despite liberibacters representing potential quarantine organisms, 'Ca. L. europaeus', first described in Italy and Europe, apparently behaves as an endophyte rather than a pathogen. more...
- Published
- 2011
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43. Distinct rpsC single nucleotide polymorphism lineages of Flavescence dorée subgroup 16SrV-D phytoplasma co-infect Vitis vinifera L.
- Author
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Quaglino F, Casati P, and Bianco PA
- Subjects
- Cluster Analysis, DNA Fingerprinting, DNA, Bacterial chemistry, DNA, Bacterial genetics, DNA, Ribosomal genetics, Italy, Molecular Sequence Data, Phylogeny, Phytoplasma genetics, Polymerase Chain Reaction, Polymorphism, Restriction Fragment Length, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Sequence Homology, Bacterial Proteins genetics, Phytoplasma classification, Phytoplasma isolation & purification, Plant Diseases microbiology, Polymorphism, Single Nucleotide, Ribosomal Proteins genetics, Vitis microbiology
- Abstract
During a survey on grapevine yellows disease complex in vineyards of Lombardy region (northern Italy), phytoplasmas associated with Flavescence dorée disease were identified in symptomatic grapevines. Polymerase chain reaction and restriction fragment length polymorphism (RFLP) analyses of 16S rDNA revealed the prevalence of phytoplasmal subgroup 16SrV-D. Bioinformatic analyses of nucleotide sequences of rplV and rpsC genes, amplified from 16SrV-D phytoplasma infected grapevines and cloned, underscored the presence of five confirmed rpsC single nucleotide polymorphism (SNP) lineages, determined by different combination of SNPs at nucleotide positions 29, 365, 680, and 720 of rpsC gene. Virtual and actual RFLP analyses with the enzyme TaqI validated the presence of these SNPs. Co-infections by up to four distinct rpsC SNP lineages of 16SrV-D phytoplasma were found in grapevines. These results could open new perspectives for the study of the ecology and the epidemiology of Flavescence dorée. more...
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- 2010
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44. Endophytic bacterial diversity in grapevine (Vitis vinifera L.) leaves described by 16S rRNA gene sequence analysis and length heterogeneity-PCR.
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Bulgari D, Casati P, Brusetti L, Quaglino F, Brasca M, Daffonchio D, and Bianco PA
- Subjects
- Bacteria classification, DNA, Bacterial genetics, DNA, Ribosomal genetics, Molecular Sequence Data, Plant Leaves microbiology, Sequence Analysis, DNA, Bacteria genetics, Bacteria isolation & purification, Biodiversity, Polymerase Chain Reaction methods, RNA, Ribosomal, 16S genetics, Vitis microbiology
- Abstract
Diversity of bacterial endophytes associated with grapevine leaf tissues was analyzed by cultivation and cultivation-independent methods. In order to identify bacterial endophytes directly from metagenome, a protocol for bacteria enrichment and DNA extraction was optimized. Sequence analysis of 16S rRNA gene libraries underscored five diverse Operational Taxonomic Units (OTUs), showing best sequence matches with gamma-Proteobacteria, family Enterobacteriaceae, with a dominance of the genus Pantoea. Bacteria isolation through cultivation revealed the presence of six OTUs, showing best sequence matches with Actinobacteria, genus Curtobacterium, and with Firmicutes genera Bacillus and Enterococcus. Length Heterogeneity-PCR (LH-PCR) electrophoretic peaks from single bacterial clones were used to setup a database representing the bacterial endophytes identified in association with grapevine tissues. Analysis of healthy and phytoplasma-infected grapevine plants showed that LH-PCR could be a useful complementary tool for examining the diversity of bacterial endophytes especially for diversity survey on a large number of samples. more...
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- 2009
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45. Simultaneous pancreas-kidney transplantation: evaluation of graft function, cholesterol, triglycerides, and immunosuppressive regimens.
- Author
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Stahlschmidt A, Suzigan BH, Martins CC, Swarowski F, Seelig DC, Bianco PA, Keitel E, Santos AF, Garcia CD, and Garcia VD
- Subjects
- Blood Glucose metabolism, Follow-Up Studies, Glycated Hemoglobin metabolism, Humans, Hypolipidemic Agents therapeutic use, Kidney Transplantation immunology, Kidney Transplantation mortality, Pancreas Transplantation immunology, Pancreas Transplantation mortality, Patient Selection, Retrospective Studies, Time Factors, Treatment Outcome, Cholesterol blood, Diabetes Mellitus, Type 1 surgery, Diabetic Nephropathies surgery, Immunosuppressive Agents therapeutic use, Kidney Failure, Chronic surgery, Kidney Transplantation physiology, Pancreas Transplantation physiology, Triglycerides blood
- Abstract
Aims: To evaluate pancreas graft function, use of insulin, cholesterol, triglyceride levels, prescription of lipid-lowering drugs, and immunosuppressive regimens among recipients of simultaneous pancreas-kidney transplants (SPKT), who had initial immunosuppression with tacrolimus, sirolimus, and corticosteroids., Methods: From 2000 to 2007, we performed 73 SKPT, among which we conducted a retrospective data analysis on 51 medical records of patients who had been followed for at least 6 to 72 months. We excluded from the analysis eight recipients who died before 6 months: eight with early pancreas graft losses and six for continued follow-up in other centers., Results: There were four pancreas graft losses after 6 months due in two diabetes mellitus recurrence, one posttuberculosis treatment, and one after use of nonsteroidal inflammatory medication. Mean plasma glucose levels ranged from 84 to 103 mg/dL, while glycosylated hemoglobin (HbA1) levels ranged from 5.7% to 6.2%. At 6, 12, 36, and 60 months, 80%, 91%, 86%, and 75% of recipients, respectively, had HbA1 lower than 6.5%. In the same period, 10%, 8%, 10%, and 11% of recipients became insulin-dependent. Mean cholesterol levels (mg/dL) at 6, 12, 36, and 60 month were 190, 180, 196 and 193, while triglyceride levels (mg/dL) were 162, 129, 106, and 113 respectively. Recipient's rate of lipid-lowering drug use was 18%, 21%, 20%, and 22% at 6, 12, 36, and 60 months. Mean serum creatinine levels (mg/dL) with standard deviations were 1.3 +/- 0.4, 1.5 +/- 0.4, 1.6 +/- 0.5, 1.8 +/- 0.9, at 6, 12, 36 and 60 months respectively. Nineteen recipients had sirolimus suspended and 14 recipients, tacrolimus suspended as well for various reasons., Conclusion: Mean plasma glucose levels were normal during the period. About 10% of recipients became insulin-dependent and 20% required lipid-lowering drugs. The immunosuppressive regimen protocol had to be changed in 60% of patients. more...
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- 2009
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46. A novel Bacteroidetes symbiont is localized in Scaphoideus titanus, the insect vector of Flavescence dorée in Vitis vinifera.
- Author
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Marzorati M, Alma A, Sacchi L, Pajoro M, Palermo S, Brusetti L, Raddadi N, Balloi A, Tedeschi R, Clementi E, Corona S, Quaglino F, Bianco PA, Beninati T, Bandi C, and Daffonchio D
- Subjects
- Animals, Bacteroidetes genetics, Bacteroidetes pathogenicity, Bacteroidetes ultrastructure, Base Sequence, DNA, Bacterial genetics, Fat Body microbiology, Fat Body ultrastructure, Female, Hemiptera ultrastructure, Insect Vectors ultrastructure, Male, Microscopy, Electron, Molecular Sequence Data, Ovary microbiology, Ovary ultrastructure, Phylogeny, Salivary Glands microbiology, Salivary Glands ultrastructure, Symbiosis, Bacteroidetes isolation & purification, Hemiptera microbiology, Insect Vectors microbiology, Plant Diseases microbiology, Plant Diseases parasitology, Vitis microbiology, Vitis parasitology
- Abstract
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 insect. Using length heterogeneity PCR with universal primers for bacteria we identified a major peak associated with almost all of the individuals examined (both males and females). Characterization by denaturing gradient gel electrophoresis confirmed the presence of a major band that, after sequencing, showed a 97 to 99% identity with Bacteroidetes symbionts of the "Candidatus Cardinium hertigii" group. In addition, electron microscopy of tissues of S. titanus fed for 3 months on phytoplasma-infected grapevine plants showed bacterial cells with the typical morphology of "Ca. Cardinium hertigii." This endosymbiont, tentatively designated ST1-C, was found in the cytoplasm of previtellogenic and vitellogenic ovarian cells, in the follicle cells, and in the fat body and salivary glands. In addition, cell morphologies resembling those of "Ca. Phytoplasma vitis" were detected in the midgut, and specific PCR assays indicated the presence of the phytoplasma in the gut, fat body and salivary glands. These results indicate that ST1-C and "Ca. Phytoplasma vitis" have a complex life cycle in the body of S. titanus and are colocalized in different organs and tissues. more...
- Published
- 2006
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47. Genetic variability among flavescence dorée phytoplasmas from different origins in Italy and France.
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Martini M, Botti S, Marcone C, Marzachì C, Casati P, Bianco PA, Benedetti R, and Bertaccini A
- Subjects
- DNA, Bacterial analysis, DNA, Ribosomal genetics, France, Italy, Molecular Sequence Data, Mycoplasma classification, Operon, Phylogeny, Polymorphism, Restriction Fragment Length, Sequence Alignment, Genetic Variation, Mycoplasma genetics, Plant Diseases microbiology, Vitis microbiology
- Abstract
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 subgroups among the reference strains belonging to elm yellows group (16SrV). Sequencing and phylogenetic analysis of the same ribosomal protein DNA fragment validated the delineation of 4 distinct FD strain types derived by RFLP analyses. The results supported the differentiation based on analysis of the non-ribosomal DNA fragment FD9. The phylogenetic analysis further revealed relationships and a probable evolutionary trend among the FD strains and the other representatives of elm yellows group. All the FD strains together with the reference strains ALY, RuS and JWB formed a cluster very well distinct from the EY/ULW cluster. Moreover, ALY was shown to be more closely related to three FD strain types: the Lombardia/Piemonte, the French FD70, and the French FD88/Italian FD-D strain clusters. more...
- Published
- 2002
- Full Text
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