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Duduk B, Stepanović J, Fránová J, Zwolińska A, Rekanović E, Stepanović M, Vučković N, Duduk N, Vico I. Geographical variations, prevalence, and molecular dynamics of fastidious phloem-limited pathogens infecting sugar beet across Central Europe. PLoS One 2024; 19:e0306136. [PMID: 38954690 PMCID: PMC11218978 DOI: 10.1371/journal.pone.0306136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Accepted: 06/11/2024] [Indexed: 07/04/2024] Open
Abstract
In Europe, two fastidious phloem-limited pathogens, 'Candidatus Phytoplasma solani' (16SrXII-A) and 'Candidatus Arsenophonus phytopathogenicus', are associated with rubbery taproot disease (RTD) and syndrome basses richesses (SBR) of sugar beet, respectively. Both diseases can significantly reduce yield, especially when accompanied by root rot fungi. This study investigates the presence, geographic distribution and genetic traits of fastidious pathogens and the accompanying fungus, Macrophomina phaseolina, found on sugar beet across four geographically separated plains spanning seven countries in Central Europe. The survey revealed variable incidences of symptoms linked to these fastidious pathogens in the Pannonian and Wallachian Plains, sporadic occurrence in the North European Plain, and no symptomatic sugar beet in the Bohemian Plain. Molecular analyses unveiled the occurrence of both 'Ca. P. solani' and 'Ca. A. phytopathogenicus' throughout Central Europe, with a predominance of the phytoplasma. These fastidious pathogens were detected in all six countries surveyed within the Pannonian and Wallachian Plains, with only a limited presence of various phytoplasmas was found in the North European Plain, while no fastidious pathogens were detected in Bohemia, aligning with observed symptoms. While 16S rDNA sequences of 'Ca. P. solani' remained highly conserved, multi-locus characterization of two more variable loci (tuf and stamp) unveiled distinct variability patterns across the plains. Notably, the surprising lack of variability of tuf and stamp loci within Central Europe, particularly the Pannonian Plain, contrasted their high variability in Eastern and Western Europe, corresponding to epidemic and sporadic occurrence, respectively. The current study provides valuable insights into the genetic dynamics of 'Ca. P. solani' in Central Europe, and novel findings of the presence of 'Ca. A. phytopathogenicus' in five countries (Slovakia, Czech Republic, Austria, Serbia, and Romania) and M. phaseolina in sugar beet in Slovakia. These findings emphasize the need for further investigation of vector-pathogen(s)-plant host interactions and ecological drivers of disease outbreaks.
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Affiliation(s)
- Bojan Duduk
- Institute of Pesticides and Environmental Protection, Belgrade, Serbia
| | - Jelena Stepanović
- Institute of Pesticides and Environmental Protection, Belgrade, Serbia
| | - Jana Fránová
- Biology Centre, Czech Academy of Sciences, Institute of Plant Molecular Biology, Plant Virology, Ceske Budejovice, Czech Republic
| | - Agnieszka Zwolińska
- Department of Plant Physiology, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
| | - Emil Rekanović
- Institute of Pesticides and Environmental Protection, Belgrade, Serbia
| | - Miloš Stepanović
- Institute of Pesticides and Environmental Protection, Belgrade, Serbia
| | - Nina Vučković
- University of Belgrade–Faculty of Agriculture, Belgrade, Serbia
| | - Nataša Duduk
- University of Belgrade–Faculty of Agriculture, Belgrade, Serbia
| | - Ivana Vico
- University of Belgrade–Faculty of Agriculture, Belgrade, Serbia
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Kosovac A, Rekanović E, Ćurčić Ž, Stepanović J, Duduk B. Plants under Siege: Investigating the Relevance of ' Ca. P. solani' Cixiid Vectors through a Multi-Test Study. PLANTS (BASEL, SWITZERLAND) 2023; 12:4157. [PMID: 38140484 PMCID: PMC10748216 DOI: 10.3390/plants12244157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 12/08/2023] [Accepted: 12/12/2023] [Indexed: 12/24/2023]
Abstract
Crop losses caused by the plant pathogenic bacterium 'Candidatus Phytoplasma solani' (CaPsol) underscore the need to better understand its perplexing epidemiological pathways. Hyalesthes obsoletus (Hemiptera, Cixiidae) is a prominent CaPsol vector with three plant associations in Serbia (ex Urtica dioica/HobsUd; ex Convolvulus arvensis/HobsCa; ex Crepis foetida/HobsCf). Another cixiid planthopper, Reptalus quinquecostatus (Dufour), has been recently confirmed as a noteworthy CaPsol vector. A multi-test study assessed the relevance of H. obsoletus associations and R. quinquecostatus populations from Crataegus monogyna and Prunus spinosa in CaPsol occurrence in sugar beet, maize, and tobacco. Molecular typing of the CaPsol strains transmitted to test plants in experimental trials provided the first evidence of HobsUd transmitting CaPsol tuf-a type to sugar beet, HobsCa infecting maize and tobacco with tuf-b type, and HobsCf transmitting CaPsol tuf-b to maize. Affiliation of R. quinquecostatus with the specific CaPsol genotype, dSTOLg, was reaffirmed in this study. The possible involvement of R. quinquecostatus in maize redness disease and tobacco stolbur was suggested, given that this cixiid was identified as a vector of CaPsol to these crops. The obtained results indicate that the tested vectors pose a threat to cultivated plants in Serbia, underscoring the need to recognize their relevance in CaPsol disease occurrences.
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Affiliation(s)
- Andrea Kosovac
- Institute of Pesticides and Environmental Protection, 11080 Belgrade, Serbia; (E.R.); (J.S.); (B.D.)
| | - Emil Rekanović
- Institute of Pesticides and Environmental Protection, 11080 Belgrade, Serbia; (E.R.); (J.S.); (B.D.)
| | - Živko Ćurčić
- Institute of Field and Vegetable Crops, 21000 Novi Sad, Serbia;
| | - Jelena Stepanović
- Institute of Pesticides and Environmental Protection, 11080 Belgrade, Serbia; (E.R.); (J.S.); (B.D.)
| | - Bojan Duduk
- Institute of Pesticides and Environmental Protection, 11080 Belgrade, Serbia; (E.R.); (J.S.); (B.D.)
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Duduk B, Ćurčić Ž, Stepanović J, Böhm JW, Kosovac A, Rekanović E, Kube M. Prevalence of a ' Candidatus Phytoplasma solani'-Related Strain Designated as New 16SrXII-P Subgroup over ' Candidatus Arsenophonus phytopathogenicus' in Sugar Beet in Eastern Germany. PLANT DISEASE 2023; 107:3792-3800. [PMID: 37189042 DOI: 10.1094/pdis-04-23-0613-re] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Two phloem-limited pathogens, 'Candidatus Arsenophonus phytopathogenicus' and 'Candidatus Phytoplasma solani', threaten sugar beet production in France, Switzerland, and Germany. Previous studies of these pathogens in Germany had focused on its western and southern regions, leaving a knowledge gap about eastern Germany. Despite their importance, this study is the first to investigate phytoplasmas in sugar beet in Saxony-Anhalt, Germany. A phytoplasma strain related to 'Ca. P. solani' is found predominant in Saxony-Anhalt, unlike in France, where 'Ca. P. solani' has a minor role compared with 'Ca. A. phytopathogenicus'. The phytoplasma strain infecting sugar beet in Saxony-Anhalt was classified into a new subgroup designated as 16SrXII-P. The multilocus sequence analysis (MLSA) of nonribosomal genes of the novel phytoplasma strain showed that it is significantly different from the reference and all previously reported 'Ca. P. solani' strains including the strain from western Germany. Analyses of sugar beet samples from previous years confirmed the presence of the 16SrXII-P strain in sugar beet as early as 2020 and also in Bavaria in southern Germany. Based on 16S rDNA analysis, 'Ca. A. phytopathogenicus' in Saxony-Anhalt is identical to strains in sugar beet in other parts of Germany and France, as well as to a strain in potato from Germany. The presence and prevalence of two phytoplasmas in sugar beet in Germany suggest that more attention should be directed toward understanding phytoplasma infection in sugar beet in this country.
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Affiliation(s)
- Bojan Duduk
- Institute of Pesticides and Environmental Protection, Belgrade 11080, Serbia
| | - Živko Ćurčić
- Institute of Field and Vegetable Crops, Novi Sad 21000, Serbia
| | - Jelena Stepanović
- Institute of Pesticides and Environmental Protection, Belgrade 11080, Serbia
| | | | - Andrea Kosovac
- Institute of Pesticides and Environmental Protection, Belgrade 11080, Serbia
| | - Emil Rekanović
- Institute of Pesticides and Environmental Protection, Belgrade 11080, Serbia
| | - Michael Kube
- University of Hohenheim, Stuttgart 70599, Germany
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Dermastia M, Tomaž Š, Strah R, Lukan T, Coll A, Dušak B, Anžič B, Čepin T, Wienkoop S, Kladnik A, Zagorščak M, Riedle-Bauer M, Schönhuber C, Weckwerth W, Gruden K, Roitsch T, Pompe Novak M, Brader G. Candidate pathogenicity factor/effector proteins of ' Candidatus Phytoplasma solani' modulate plant carbohydrate metabolism, accelerate the ascorbate-glutathione cycle, and induce autophagosomes. FRONTIERS IN PLANT SCIENCE 2023; 14:1232367. [PMID: 37662165 PMCID: PMC10471893 DOI: 10.3389/fpls.2023.1232367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 07/31/2023] [Indexed: 09/05/2023]
Abstract
The pathogenicity of intracellular plant pathogenic bacteria is associated with the action of pathogenicity factors/effectors, but their physiological roles for most phytoplasma species, including 'Candidiatus Phytoplasma solani' are unknown. Six putative pathogenicity factors/effectors from six different strains of 'Ca. P. solani' were selected by bioinformatic analysis. The way in which they manipulate the host cellular machinery was elucidated by analyzing Nicotiana benthamiana leaves after Agrobacterium-mediated transient transformation with the pathogenicity factor/effector constructs using confocal microscopy, pull-down, and co-immunoprecipitation, and enzyme assays. Candidate pathogenicity factors/effectors were shown to modulate plant carbohydrate metabolism and the ascorbate-glutathione cycle and to induce autophagosomes. PoStoSP06, PoStoSP13, and PoStoSP28 were localized in the nucleus and cytosol. The most active effector in the processes studied was PoStoSP06. PoStoSP18 was associated with an increase in phosphoglucomutase activity, whereas PoStoSP28, previously annotated as an antigenic membrane protein StAMP, specifically interacted with phosphoglucomutase. PoStoSP04 induced only the ascorbate-glutathione cycle along with other pathogenicity factors/effectors. Candidate pathogenicity factors/effectors were involved in reprogramming host carbohydrate metabolism in favor of phytoplasma own growth and infection. They were specifically associated with three distinct metabolic pathways leading to fructose-6-phosphate as an input substrate for glycolysis. The possible significance of autophagosome induction by PoStoSP28 is discussed.
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Affiliation(s)
- Marina Dermastia
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
| | - Špela Tomaž
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
- Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Rebeka Strah
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
- Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Tjaša Lukan
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
| | - Anna Coll
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
| | - Barbara Dušak
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
- Department of Plant and Environmental Sciences, University of Copenhagen, Taastrup, Denmark
| | - Barbara Anžič
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
| | - Timotej Čepin
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
| | - Stefanie Wienkoop
- Department of Functional and Evolutionary Ecology, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | - Aleš Kladnik
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Maja Zagorščak
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
| | - Monika Riedle-Bauer
- Federal College and Research Institute for Viticulture and Pomology Klosterneuburg, Klosterneuburg, Austria
| | - Christina Schönhuber
- Bioresources Unit, Health & Environment Department, Austrian Institute of Technology, Tulln, Austria
| | - Wolfram Weckwerth
- Department of Functional and Evolutionary Ecology, Faculty of Life Sciences, University of Vienna, Vienna, Austria
- Vienna Metabolomics Center (VIME), University of Vienna, Vienna, Austria
| | - Kristina Gruden
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
| | - Thomas Roitsch
- Department of Plant and Environmental Sciences, University of Copenhagen, Taastrup, Denmark
| | - Maruša Pompe Novak
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
- Faculty of Viticulture and Enology, University of Nova Gorica, Vipava, Slovenia
| | - Günter Brader
- Bioresources Unit, Health & Environment Department, Austrian Institute of Technology, Tulln, Austria
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Riedle-Bauer M, Brader G. Effects of insecticides and repellents on the spread of ' Candidatus Phytoplasma solani' under laboratory and field conditions. JOURNAL OF PLANT DISEASES AND PROTECTION : SCIENTIFIC JOURNAL OF THE GERMAN PHYTOMEDICAL SOCIETY (DPG) 2023; 130:1057-1074. [PMID: 37576720 PMCID: PMC10421767 DOI: 10.1007/s41348-023-00768-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 06/06/2023] [Indexed: 08/15/2023]
Abstract
Recent outbreaks of 'Candidatus Phytoplasma solani' resulted in severe losses in potatoes, vegetable crops and grapevines in certain regions of Austria and constituted a major challenge for seed potato production. Therefore, the effects of various insecticides and insect deterrents on pathogen spread were studied both in laboratory and field experiments from 2018 to 2021. In laboratory transmission experiments, field captured Hyalesthes obsoletus were caged on differently treated Catharanthus roseus for five days. The insecticides lambda-cyhalothrin, deltamethrin, esfenvalerate, acetamiprid and chlorpyriphos showed the most rapid impact on insect survival and fully prevented phytoplasma transmission. The particle film forming products kaolin and diatomaceous earth had some effect. A transfer of the promising laboratory results to potato fields, however, was achieved to a limited extent only. Treatments with pyrethroids and acetamiprid every 8-10 days over the flight period of H. obsoletus roughly halved the number of symptomatic plants and tubers in case of moderately susceptible varieties and moderate infection pressure. In the event of susceptible varieties and high disease pressure, treatment effects were hardy discernible. In practical terms, the experiments indicate that insecticide applications alone are not sufficient to mitigate the disease. Spraying of diatomaceous earth and mineral oil did not affect disease incidence in the field. Supplementary Information The online version contains supplementary material available at 10.1007/s41348-023-00768-y.
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Affiliation(s)
- Monika Riedle-Bauer
- Federal College and Research Institute for Viticulture and Pomology Klosterneuburg, Wienerstraße 74, 3400 Klosterneuburg, Austria
| | - Günter Brader
- AIT Austrian Institute of Technology GmbH, Konrad-Lorenz-Straße 24, 3430 Tulln, Austria
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Kosovac A, Ćurčić Ž, Stepanović J, Rekanović E, Duduk B. Epidemiological role of novel and already known 'Ca. P. solani' cixiid vectors in rubbery taproot disease of sugar beet in Serbia. Sci Rep 2023; 13:1433. [PMID: 36697493 PMCID: PMC9877035 DOI: 10.1038/s41598-023-28562-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 01/20/2023] [Indexed: 01/26/2023] Open
Abstract
Rubbery taproot disease (RTD) of sugar beet was recently associated with the plant pathogenic bacterium 'Candidatus Phytoplasma solani' (CaPsol) and reported throughout the Pannonian Plain with variations in severity. Tracing CaPsol epidemiological pathways was performed in the experimental sugar beet field in Rimski Šančevi (Serbia) in 2020-2021, where an RTD outbreak was recently recorded. A molecular epidemiology approach was applied to the study of three RTD occurrence scenarios: epidemic, non-epidemic and 'absence of RTD'. As a result, Hyalesthes obsoletus ex Convolvulus arvensis was detected as a CaPsol vector to sugar beet, while two other cixiids were identified for the first time as vectors of the CaPsol-induced plant disease in crops: Reptalus quinquecostatus and R. cuspidatus. R. quinquecostatus was proposed culpable for the 2020 RTD epidemic outbreak in Rimski Šančevi when dSTOLg CaPsol strain predominated in the RTD-affected sugar beet, whereas R. cuspidatus had a negligible role in RTD occurrence and displayed ambiguous involvement in CaPsol epidemiology on a wider scale. The temporal discrepancy of the offset of CaPsol dissemination and disease occurrence is the main obstacle in predicting CaPsol-induced diseases. Predicting disease occurrence and severity can only be achieved by gaining a better understanding of CaPsol epidemiological pathways and insect vectors involved in disease outbreaks.
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Affiliation(s)
- Andrea Kosovac
- Laboratory of Phytopathology, Institute of Pesticides and Environmental Protection, 11080, Belgrade, Serbia.
| | - Živko Ćurčić
- Sunflower Department, Institute of Field and Vegetable Crops, 21000, Novi Sad, Serbia
| | - Jelena Stepanović
- Laboratory of Phytopathology, Institute of Pesticides and Environmental Protection, 11080, Belgrade, Serbia
| | - Emil Rekanović
- Laboratory of Phytopathology, Institute of Pesticides and Environmental Protection, 11080, Belgrade, Serbia
| | - Bojan Duduk
- Laboratory of Phytopathology, Institute of Pesticides and Environmental Protection, 11080, Belgrade, Serbia
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Duduk N, Vico I, Kosovac A, Stepanović J, Ćurčić Ž, Vučković N, Rekanović E, Duduk B. A biotroph sets the stage for a necrotroph to play: ' Candidatus Phytoplasma solani' infection of sugar beet facilitated Macrophomina phaseolina root rot. Front Microbiol 2023; 14:1164035. [PMID: 37152751 PMCID: PMC10158981 DOI: 10.3389/fmicb.2023.1164035] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Accepted: 03/31/2023] [Indexed: 05/09/2023] Open
Abstract
'Candidatus Phytoplasma solani' (stolbur phytoplasma) is associated with rubbery taproot disease (RTD) of sugar beet (Beta vulgaris L.), while Macrophomina phaseolina is considered the most important root rot pathogen of this plant in Serbia. The high prevalence of M. phaseolina root rot reported on sugar beet in Serbia, unmatched elsewhere in the world, coupled with the notorious tendency of RTD-affected sugar beet to rot, has prompted research into the relationship between the two diseases. This study investigates the correlation between the occurrence of sugar beet RTD and the presence of root rot fungal pathogens in a semi-field 'Ca. P. solani' transmission experiment with the cixiid vector Reptalus quinquecostatus (Dufour), in addition to naturally infected sugar beet in the open field. Our results showed that: (i) Reptalus quinquecostatus transmitted 'Ca. P. solani' to sugar beet which induced typical RTD root symptoms; (ii) Macrophomina phaseolina root rot was exclusively present in 'Ca. P. solani'-infected sugar beet in both the semi-field experiment and naturally infected sugar beet; and that (iii) even under environmental conditions favorable to the pathogen, M. phaseolina did not infect sugar beet, unless the plants had been previously infected with phytoplasma.
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Affiliation(s)
- Nataša Duduk
- Faculty of Agriculture, University of Belgrade, Belgrade, Serbia
- *Correspondence: Nataša Duduk,
| | - Ivana Vico
- Faculty of Agriculture, University of Belgrade, Belgrade, Serbia
| | - Andrea Kosovac
- Institute of Pesticides and Environmental Protection, Belgrade, Serbia
| | - Jelena Stepanović
- Institute of Pesticides and Environmental Protection, Belgrade, Serbia
| | - Živko Ćurčić
- Institute of Field and Vegetable Crops, Novi Sad, Serbia
| | - Nina Vučković
- Faculty of Agriculture, University of Belgrade, Belgrade, Serbia
| | - Emil Rekanović
- Institute of Pesticides and Environmental Protection, Belgrade, Serbia
| | - Bojan Duduk
- Institute of Pesticides and Environmental Protection, Belgrade, Serbia
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Çağlar BK, Şimşek E. Detection and Multigene Typing of ' Candidatus Phytoplasma solani'-Related Strains Infecting Tomato and Potato Plants in Different Regions of Turkey. Pathogens 2022; 11:1031. [PMID: 36145463 PMCID: PMC9505192 DOI: 10.3390/pathogens11091031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 09/02/2022] [Accepted: 09/08/2022] [Indexed: 11/27/2022] Open
Abstract
'Candidatus Phytoplasma solani' ('Ca. P. solani') is a crop pathogen that is a member of the 16SrXII-A ribosomal subgroup. It is also known as stolbur phytoplasma and causes yield losses in several important crops, especially in Solanaceous crops. Different strains of the pathogen are regularly reported all over the world, particularly in the Mediterranean region. In this study, the determination of genetic diversity for the pathogen infecting tomatoes and potatoes was carried out by using multilocus sequence typing analysis for the Tuf, SecY, and Vmp1 genes to gain insight into the epidemiology of 'Ca. P. solani' in Turkey. Genetic diversity of the phytoplasmas was investigated by sequence-based phylogenetic analyses and in silico RFLP analysis of related genes. It was determined that all 'Ca. P. solani'-related strains infecting tomatoes and potatoes were tuf-b, which is linked to field bindweed (Convolvulus arvensis L.). Tomato or potato-infecting 'Ca. P. solani'-related strains showed similarities with each other; however, the isolates collected from different plants showed genetic differences in terms of the SecY gene. This study indicates that the highest genetic variability of collected samples was found in the Vmp1 gene. RsaI-RFLP analysis of TYPH10F/R amplicons showed that potato-infecting 'Ca. P. solani'-related strains were found to be similar to some existing V types. However, the V-type of tomato-infecting isolates is not similar to any previously reported V-type. The results indicate that there could be an important genetic diversity of 'Ca. P. solani'-related phytoplasmas in Turkey. This could indicate various ways in which the pathogen has adapted to the two host plants as a consequence of the various Vmp1 gene rearrangements seen in these two plant hosts. Obtained results also indicate that the epidemiology of 'Ca. P. solani'-related phytoplasmas in the tomato and potato agroecosystem may be better understood with the use of molecular data on the complex of vmp-types.
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Affiliation(s)
- Behçet Kemal Çağlar
- Department of Plant Protection, Faculty of Agriculture, Çukurova University, Adana 01330, Turkey
| | - Eray Şimşek
- Department of Plant Protection, Faculty of Agriculture, Harran University, Şanlıurfa 63290, Turkey
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Jamshidi E, Murolo S, Ravari SB, Salehi M, Romanazzi G. Multilocus Genotyping of ‘Candidatus Phytoplasma Solani’ Associated with Grapevine Bois Noir in Iran. BIOLOGY 2022; 11:biology11060835. [PMID: 35741356 PMCID: PMC9220303 DOI: 10.3390/biology11060835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 05/23/2022] [Accepted: 05/26/2022] [Indexed: 11/16/2022]
Abstract
Simple Summary Understanding the epidemiological cycle of Bois noir (BN) associated with ‘Candidatus Phytoplasma solani’ is vital to managing the disease effectively. The genotyping of ‘Ca. P. solani’ strains, according to tuf, vmp1, and stamp genes, contributes to a better knowledge of the geographical distribution of BN. In this study, we provide information on the molecular variants of ‘Ca. P. solani’ in Iranian vineyards. We observed six known vmp1 variants and discovered two new ones, V24 and V27. This information is useful for future investigations to more accurately understand the epidemiological cycle(s) of BN in Iranian vineyards, contributing to the management of the disease. Abstract Grapevine Bois noir (BN) is associated with ‘Candidatus Phytoplasma solani’. It has been recorded in vineyards throughout Europe as well as in different countries in Asia, where it now constitutes a threat to Iranian viticulture. BN is strictly dependent on ‘Ca. P. solani’ strains, wild host plants, and insect vectors. The molecular typing of ‘Ca. P. solani’, based on the nonribosomal gene tuf and the two hypervariable markers vmp1 and stamp, is valuable for the reconstruction and clarification of the pathways of BN spread. In this study, an RFLP analysis was performed on the vmp1 gene, and a single-nucleotide polymorphism analysis confirmed new vmp types in ‘Ca. P. solani’. A stamp gene phylogenetic analysis allowed us to distinguish between the new genotype infections in the grapevines and the ‘weeds’ Convolvulus arvensis and Erigeron bonariensis in Iranian vineyards, highlighting the close genetic relatedness of the strains of ‘Ca. P. solani’ found in Iran and Azerbaijan. The most common genotype in the grapevines was tuf b/V24/stamp III, which was associated with C. arvensis. This information contributes toward the identification of further routes of introduction of ‘Ca. P. solani’ in Iran to sustain the control measures for the management of BN.
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Affiliation(s)
- Elham Jamshidi
- Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, I-60131 Ancona, Italy; (E.J.); (S.M.)
| | - Sergio Murolo
- Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, I-60131 Ancona, Italy; (E.J.); (S.M.)
| | - Sareh Baghaee Ravari
- Plant Protection Department, Ferdowsi University of Mashhad, Mashhad 1696700, Iran;
| | - Mohammad Salehi
- Plant Protection Research Department, Fars Agricultural and Natural Resources Research and Education Centre, AREEO, Zarghan 73415-111, Iran;
| | - Gianfranco Romanazzi
- Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, I-60131 Ancona, Italy; (E.J.); (S.M.)
- Correspondence: ; Tel.: +39-071-2204336
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Mehle N, Kavčič S, Mermal S, Vidmar S, Pompe Novak M, Riedle-Bauer M, Brader G, Kladnik A, Dermastia M. Geographical and Temporal Diversity of ' Candidatus Phytoplasma solani' in Wine-Growing Regions in Slovenia and Austria. FRONTIERS IN PLANT SCIENCE 2022; 13:889675. [PMID: 35668796 PMCID: PMC9164133 DOI: 10.3389/fpls.2022.889675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 04/11/2022] [Indexed: 06/15/2023]
Abstract
As the causal agent of the grapevine yellows disease Bois noir, 'Candidatus Phytoplasma solani' has a major economic impact on grapevines. To improve the control of Bois noir, it is critical to understand the very complex epidemiological cycles that involve the multiple "Ca. P. solani" host plants and insect vectors, of which Hyalesthes obsoletus is the most important. In the present study, multiple genotyping of the tuf, secY, stamp, and vmp1 genes was performed. This involved archived grapevine samples that were collected during an official survey of grapevine yellows throughout the wine-growing regions of Slovenia (from 2003 to 2016), plus samples from Austrian grapevines, stinging nettle, field bindweed, and insect samples (collected from 2012 to 2019). The data show that the tuf-b2 type of the tuf gene has been present in eastern Slovenia since at least 2003. The hypotheses that the occurrence of the haplotypes varies due to the geographical position of Slovenia on the Italian-Slovenian Karst divide and that the haplotypes are similar between Slovenian and Austrian Styria were confirmed. The data also show haplotype changes for host plants and H. obsoletus associated with 'Ca. P. solani,' which might be linked to new epidemiological cycles of this phytoplasma that involve not just new plant sources and new insect vectors, but also climate and land-use changes.
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Affiliation(s)
- Nataša Mehle
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
- Faculty of Viticulture and Enology, University of Nova Gorica, Vipava, Slovenia
| | - Sanda Kavčič
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
| | - Sara Mermal
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
| | - Sara Vidmar
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
| | - Maruša Pompe Novak
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
- Faculty of Viticulture and Enology, University of Nova Gorica, Vipava, Slovenia
| | - Monika Riedle-Bauer
- Federal College and Research Institute for Viticulture and Pomology Klosterneuburg, Klosterneuburg, Austria
| | - Günter Brader
- Center for Health & Bioresources, Austrian Institute of Technology, Tulln, Austria
| | - Aleš Kladnik
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Marina Dermastia
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
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11
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Marasco R, Alturkey H, Fusi M, Brandi M, Ghiglieno I, Valenti L, Daffonchio D. Rootstock-scion combination contributes to shape diversity and composition of microbial communities associated with grapevine root system. Environ Microbiol 2022; 24:3791-3808. [PMID: 35581159 PMCID: PMC9544687 DOI: 10.1111/1462-2920.16042] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 05/06/2022] [Indexed: 12/01/2022]
Abstract
To alleviate biotic and abiotic stresses and enhance fruit yield, many crops are cultivated in the form of grafted plants, in which the shoot (scion) and root (rootstock) systems of different species are joined together. Because (i) the plant species determines the microbial recruitment from the soil to the root and (ii) both scion and rootstock impact the physiology, morphology and biochemistry of the grafted plant, it can be expected that their different combinations should affect the recruitment and assembly of plant microbiome. To test our hypothesis, we investigated at a field scale the bacterial and fungal communities associated with the root system of seven grapevine rootstock–scion combinations cultivated across 10 different vineyards. Following the soil type, which resulted in the main determinant of the grapevine root microbial community diversity, the rootstock–scion combination resulted more important than the two components taken alone. Notably, the microbiome differences among the rootstock–scion combinations were mainly dictated by the changes in the relative abundance of microbiome members rather than by their presence/absence. These results reveal that the microbiome of grafted grapevine root systems is largely influenced by the combination of rootstock and scion, which affects the microbial diversity uptaken from soil.
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Affiliation(s)
- Ramona Marasco
- Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Hend Alturkey
- Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Marco Fusi
- Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Michele Brandi
- Marchesi Frescobaldi Società Agricola s.p.a. Fattoria Poggio a Remole, Sieci, Italy
| | - Isabella Ghiglieno
- Department of Agricultural and Environmental Sciences - Production, Landscape, Agroenergy, University of Milan, Milan, Italy.,Department of Civil, Environmental, Architectural Engineering and Mathematics (DICATAM), University of Brescia, Agrofood Research Hub, Brescia, Italy
| | - Leonardo Valenti
- Department of Agricultural and Environmental Sciences - Production, Landscape, Agroenergy, University of Milan, Milan, Italy
| | - Daniele Daffonchio
- Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
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12
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In Silico Three-Dimensional (3D) Modeling of the SecY Protein of ‘Candidatus Phytoplasma Solani’ Strains Associated with Grapevine “Bois Noir” and Its Possible Relationship with Strain Virulence. INTERNATIONAL JOURNAL OF PLANT BIOLOGY 2022. [DOI: 10.3390/ijpb13020004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Grapevine “bois noir”, related to the presence of ‘Candidatus Phytoplasma solani’ (‘Ca. P. solani’), represents a serious threat in several vine-growing areas worldwide. In surveys conducted over two years, mild and/or moderate symptoms and lower pathogen titer were mainly associated with ‘Ca. P. solani’ strains harboring a secY gene sequence variant (secY52), whereas severe symptoms and higher titer were mainly observed in grapevines infected by phytoplasma strains carrying any one of another four variants. A comparison of amino acid sequences of the protein SecY of ‘Ca. P. solani’ strains revealed the presence of conservative and semi-conservative substitutions. The deduced three-dimensional (3D) protein analysis unveiled that one semi-conservative substitution identified in the sequence variant secY52 is responsible for a structural disordered region that probably confers a flexibility for binding to distinct molecular complexes. In fact, the other analyzed variants show an organized structure and the 3D in silico prediction allowed the identification of β-sheets. Thus, differences in symptom severity and pathogen concentration observed in grapevines infected by ‘Ca. P. solani’ strains carrying distinct secY gene sequence variants suggest a possible relationship between SecY protein structure and phytoplasma strain virulence.
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13
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Contaldo N, Stepanović J, Pacini F, Bertaccini A, Duduk B. Molecular Variability and Host Distribution of ' Candidatus Phytoplasma solani' Strains from Different Geographic Origins. Microorganisms 2021; 9:microorganisms9122530. [PMID: 34946132 PMCID: PMC8705599 DOI: 10.3390/microorganisms9122530] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 11/29/2021] [Accepted: 12/01/2021] [Indexed: 11/30/2022] Open
Abstract
The knowledge of phytoplasma genetic variability is a tool to study their epidemiology and to implement an effective monitoring and management of their associated diseases. ‘Candidatus Phytoplasma solani’ is associated with “bois noir” disease in grapevines, and yellowing and decline symptoms in many plant species, causing serious damages during the epidemic outbreaks. The epidemiology of the diseases associated with this phytoplasma is complex and related to numerous factors, such as interactions of the host plant and insect vectors and spreading through infected plant propagation material. The genetic variability of ‘Ca. P. solani’ strains in different host species and in different geographic areas during the last two decades was studied by RFLP analyses coupled with sequencing on vmp1, stamp, and tuf genes. A total of 119 strains were examined, 25 molecular variants were identified, and the variability of the studied genes was linked to both geographic distribution and year of infection. The crucial question in ‘Ca. P. solani’ epidemiology is to trace back the epidemic cycle of the infections. This study presents some relevant features about differential strain distribution useful for disease monitoring and forecasting, illustrating and comparing the phytoplasma molecular variants identified in various regions, host species, and time periods.
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Affiliation(s)
- Nicoletta Contaldo
- Department of Agricultural and Food Sciences, Alma Mater Studiorum-University of Bologna, 40127 Bologna, Italy; (F.P.); (A.B.)
- Correspondence:
| | - Jelena Stepanović
- Institute of Pesticides and Environmental Protection, 11080 Belgrade, Serbia; (J.S.); (B.D.)
| | - Francesco Pacini
- Department of Agricultural and Food Sciences, Alma Mater Studiorum-University of Bologna, 40127 Bologna, Italy; (F.P.); (A.B.)
| | - Assunta Bertaccini
- Department of Agricultural and Food Sciences, Alma Mater Studiorum-University of Bologna, 40127 Bologna, Italy; (F.P.); (A.B.)
| | - Bojan Duduk
- Institute of Pesticides and Environmental Protection, 11080 Belgrade, Serbia; (J.S.); (B.D.)
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14
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Ćurčić Ž, Kosovac A, Stepanović J, Rekanović E, Kube M, Duduk B. Multilocus Genotyping of ' Candidatus Phytoplasma solani' Associated with Rubbery Taproot Disease of Sugar Beet in the Pannonian Plain. Microorganisms 2021; 9:microorganisms9091950. [PMID: 34576845 PMCID: PMC8470437 DOI: 10.3390/microorganisms9091950] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 09/07/2021] [Accepted: 09/07/2021] [Indexed: 11/16/2022] Open
Abstract
Rubbery taproot disease of sugar beet (RTD), associated with ‘Candidatus Phytoplasma solani’, appeared in 2020 on an epidemic scale in northern Serbia and southern Slovakia, situated at opposite edges of the Pannonian Plain. In the affected locations where the disease was assessed, symptomatic sugar beets were analysed for phytoplasma infection. Additionally, multilocus sequence analyses of ‘Ca. P. solani’ strains on epidemiologically informative marker genes (tuf, stamp and vmp1) were performed. Symptomatic sugar beets from other countries of the Pannonian Plain (Croatia, Hungary and Austria), one sample from Germany, and red beets from Serbia were included in the analyses. ‘Ca. P. solani’ was detected in sugar beet in all assessed countries, as well as in red beet. Molecular analyses revealed the high genetic variability of ‘Ca. P. solani’ with the presence of all four tuf-types (a, b1, b2 and d), 14 stamp genotypes (seven new) and five vmp1 profiles (one new). The most common multilocus genotype in Serbia, Slovakia, Croatia, and Hungary was dSTOLg (tuf-d/STOL/V2-TA). It was dominant on sites with epidemic RTD outbreaks in the Pannonian Plain and in several sugar beet fields with non-epidemic RTD occurrence suggesting the prevalence of a particular epidemiological pathway during the epidemic’s phases.
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Affiliation(s)
- Živko Ćurčić
- Institute of Field and Vegetable Crops, 21000 Novi Sad, Serbia;
| | - Andrea Kosovac
- Institute of Pesticides and Environmental Protection, 11080 Belgrade, Serbia; (A.K.); (J.S.); (E.R.)
| | - Jelena Stepanović
- Institute of Pesticides and Environmental Protection, 11080 Belgrade, Serbia; (A.K.); (J.S.); (E.R.)
| | - Emil Rekanović
- Institute of Pesticides and Environmental Protection, 11080 Belgrade, Serbia; (A.K.); (J.S.); (E.R.)
| | - Michael Kube
- Department of Integrative Infection Biology Crops-Livestock, University of Hohenheim, 70599 Stuttgart, Germany;
| | - Bojan Duduk
- Institute of Pesticides and Environmental Protection, 11080 Belgrade, Serbia; (A.K.); (J.S.); (E.R.)
- Correspondence: ; Tel.: +381-11-3076133
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15
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Škrlj B, Novak MP, Brader G, Anžič B, Ramšak Ž, Gruden K, Kralj J, Kladnik A, Lavrač N, Roitsch T, Dermastia M. New Cross-Talks between Pathways Involved in Grapevine Infection with ' Candidatus Phytoplasma solani' Revealed by Temporal Network Modelling. PLANTS (BASEL, SWITZERLAND) 2021; 10:646. [PMID: 33805409 PMCID: PMC8065506 DOI: 10.3390/plants10040646] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 03/18/2021] [Accepted: 03/24/2021] [Indexed: 12/17/2022]
Abstract
Understanding temporal biological phenomena is a challenging task that can be approached using network analysis. Here, we explored whether network reconstruction can be used to better understand the temporal dynamics of bois noir, which is associated with 'Candidatus Phytoplasma solani', and is one of the most widespread phytoplasma diseases of grapevine in Europe. We proposed a methodology that explores the temporal network dynamics at the community level, i.e., densely connected subnetworks. The methodology offers both insights into the functional dynamics via enrichment analysis at the community level, and analyses of the community dissipation, as a measure that accounts for community degradation. We validated this methodology with cases on experimental temporal expression data of uninfected grapevines and grapevines infected with 'Ca. P. solani'. These data confirm some known gene communities involved in this infection. They also reveal several new gene communities and their potential regulatory networks that have not been linked to 'Ca. P. solani' to date. To confirm the capabilities of the proposed method, selected predictions were empirically evaluated.
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Affiliation(s)
- Blaž Škrlj
- Jožef Stefan International Postgraduate School, 1000 Ljubljana, Slovenia;
- Jožef Stefan Institute, 1000 Ljubljana, Slovenia;
| | - Maruša Pompe Novak
- National Institute of Biology, 1000 Ljubljana, Slovenia; (M.P.N.); (B.A.); (Ž.R.); (K.G.); (M.D.)
- School of Viticulture and Enology, University of Nova Gorica, 5271 Vipava, Slovenia
| | - Günter Brader
- Austrian Institute of Technology, Bioresources Unit, 3430 Tulln, Austria;
| | - Barbara Anžič
- National Institute of Biology, 1000 Ljubljana, Slovenia; (M.P.N.); (B.A.); (Ž.R.); (K.G.); (M.D.)
| | - Živa Ramšak
- National Institute of Biology, 1000 Ljubljana, Slovenia; (M.P.N.); (B.A.); (Ž.R.); (K.G.); (M.D.)
| | - Kristina Gruden
- National Institute of Biology, 1000 Ljubljana, Slovenia; (M.P.N.); (B.A.); (Ž.R.); (K.G.); (M.D.)
| | - Jan Kralj
- Jožef Stefan Institute, 1000 Ljubljana, Slovenia;
| | - Aleš Kladnik
- Department of Biology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia;
| | - Nada Lavrač
- Jožef Stefan International Postgraduate School, 1000 Ljubljana, Slovenia;
- Jožef Stefan Institute, 1000 Ljubljana, Slovenia;
| | - Thomas Roitsch
- Department of Plant and Environmental Sciences, University of Copenhagen, 2630 Taastrup, Denmark;
| | - Marina Dermastia
- National Institute of Biology, 1000 Ljubljana, Slovenia; (M.P.N.); (B.A.); (Ž.R.); (K.G.); (M.D.)
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16
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Differential Response of Grapevine to Infection with ' Candidatus Phytoplasma solani' in Early and Late Growing Season through Complex Regulation of mRNA and Small RNA Transcriptomes. Int J Mol Sci 2021; 22:ijms22073531. [PMID: 33805429 PMCID: PMC8037961 DOI: 10.3390/ijms22073531] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/24/2021] [Accepted: 03/25/2021] [Indexed: 02/08/2023] Open
Abstract
Bois noir is the most widespread phytoplasma grapevine disease in Europe. It is associated with ‘Candidatus Phytoplasma solani’, but molecular interactions between the causal pathogen and its host plant are not well understood. In this work, we combined the analysis of high-throughput RNA-Seq and sRNA-Seq data with interaction network analysis for finding new cross-talks among pathways involved in infection of grapevine cv. Zweigelt with ‘Ca. P. solani’ in early and late growing seasons. While the early growing season was very dynamic at the transcriptional level in asymptomatic grapevines, the regulation at the level of small RNAs was more pronounced later in the season when symptoms developed in infected grapevines. Most differentially expressed small RNAs were associated with biotic stress. Our study also exposes the less-studied role of hormones in disease development and shows that hormonal balance was already perturbed before symptoms development in infected grapevines. Analysis at the level of communities of genes and mRNA-microRNA interaction networks revealed several new genes (e.g., expansins and cryptdin) that have not been associated with phytoplasma pathogenicity previously. These novel actors may present a new reference framework for research and diagnostics of phytoplasma diseases of grapevine.
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Jović J, Marinković S, Jakovljević M, Krstić O, Cvrković T, Mitrović M, Toševski I. Symptomatology, (Co)occurrence and Differential Diagnostic PCR Identification of ' Ca. Phytoplasma solani' and ' Ca. Phytoplasma convolvuli' in Field Bindweed. Pathogens 2021; 10:pathogens10020160. [PMID: 33546447 PMCID: PMC7913610 DOI: 10.3390/pathogens10020160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Revised: 01/20/2021] [Accepted: 01/29/2021] [Indexed: 11/16/2022] Open
Abstract
Field bindweed (Convolvulus arvensis) is one of the major natural plant hosts and reservoirs of ‘Candidatus Phytoplasma solani’ (‘Ca. P. solani’), the causal agent of plant diseases in diverse agricultural crops, including Bois noir (BN) disease of grapevine. Phylogenetically, the most closely related phytoplasma to ‘Ca. P. solani’, the ‘Ca. P. convolvuli’, induces disease in field bindweed that is known by its symptoms as bindweed yellows (BY). The occurrence, coinfection and symptoms association of the two phytoplasmas in shared host plants were the subject of this study. Specific primers for the amplification of the elongation factor Tu gene (tuf) were developed for the identification of ‘Ca. P. convolvuli’ (by conventional nested PCR), as well as primers for simultaneous detection of ‘Ca. P. solani’ and ‘Ca. P. convolvuli’ by duplex SYBR Green real-time PCR. Among symptomatic bindweed plants, 25 and 41% were infected with a single phytoplasma species, ‘Ca. P. solani’ and ‘Ca. P. convolvuli’, respectively, while 34% were infected with both phytoplasmas. None of the non-symptomatic control plants carried phytoplasma, while non-symptomatic plants from our previous epidemiological studies in BN-affected vineyards were confirmed to be infected solely with ‘Ca. P. solani’. Stamp gene typing revealed Rqg50 and Rqg31 ‘Ca. P. solani’ genotypes in plants coinfected with ‘Ca. P. convolvuli’, while three diverse genotypes (Rqg50, GGY and Rpm35) were identified in a single locality with symptomatic bindweeds infected solely with ‘Ca. P. solani’. Variations in symptoms and their association with each of the phytoplasmas are described and documented. The symptom of bushy appearance could be single out as specific for ‘Ca. P. convolvuli’ infection, while occurrence of ‘Ca. P. solani’ could not be unequivocally associated with specific alterations in infected bindweeds. The results are discussed in the context of the epidemiological and ecological complexity of ‘Ca. P. solani’-induced diseases and the relationship between the two phytoplasma relatives in shared host plant.
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Affiliation(s)
- Jelena Jović
- Department of Plant Pests, Institute for Plant Protection and Environment, 11080 Zemun, Serbia; (S.M.); (M.J.); (O.K.); (T.C.); (M.M.); (I.T.)
- Correspondence: or
| | - Slavica Marinković
- Department of Plant Pests, Institute for Plant Protection and Environment, 11080 Zemun, Serbia; (S.M.); (M.J.); (O.K.); (T.C.); (M.M.); (I.T.)
| | - Miljana Jakovljević
- Department of Plant Pests, Institute for Plant Protection and Environment, 11080 Zemun, Serbia; (S.M.); (M.J.); (O.K.); (T.C.); (M.M.); (I.T.)
| | - Oliver Krstić
- Department of Plant Pests, Institute for Plant Protection and Environment, 11080 Zemun, Serbia; (S.M.); (M.J.); (O.K.); (T.C.); (M.M.); (I.T.)
| | - Tatjana Cvrković
- Department of Plant Pests, Institute for Plant Protection and Environment, 11080 Zemun, Serbia; (S.M.); (M.J.); (O.K.); (T.C.); (M.M.); (I.T.)
| | - Milana Mitrović
- Department of Plant Pests, Institute for Plant Protection and Environment, 11080 Zemun, Serbia; (S.M.); (M.J.); (O.K.); (T.C.); (M.M.); (I.T.)
| | - Ivo Toševski
- Department of Plant Pests, Institute for Plant Protection and Environment, 11080 Zemun, Serbia; (S.M.); (M.J.); (O.K.); (T.C.); (M.M.); (I.T.)
- CABI, 2800 Delémont, Switzerland
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Ćurčić Ž, Stepanović J, Zübert C, Taški-Ajduković K, Kosovac A, Rekanović E, Kube M, Duduk B. Rubbery Taproot Disease of Sugar Beet in Serbia Associated with ' Candidatus Phytoplasma solani'. PLANT DISEASE 2021; 105:255-263. [PMID: 33021915 DOI: 10.1094/pdis-07-20-1602-re] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Rubbery taproot disease (RTD) of sugar beet was observed in Serbia for the first time in the 1960s. The disease was already described in neighboring Bulgaria and Romania at the time but it was associated with abiotic factors. In this study on RTD of sugar beet in its main growing area of Serbia, we provide evidence of the association between 'Candidatus Phytoplasma solani' (stolbur phytoplasma) infection and the occurrence of typical RTD symptomatology. 'Ca. P. solani' was identified by PCR and the sequence analyses of 16S ribosomal RNA, tuf, secY, and stamp genes. In contrast, the causative agent of the syndrome "basses richesses" of sugar beet-namely, 'Ca. Arsenophonus phytopathogenicus'-was not detected. Sequence analysis of the stolbur strain's tuf gene confirmed a previously reported and a new, distinct tuf stolbur genotype (named 'tuf d') that is prevalent in sugar beet. The sequence signatures of the tuf gene as well as the one of stamp both correlate with the epidemiological cycle and reservoir plant host. This study provides knowledge that, for the first time, enables the differentiation of stolbur strains associated with RTD of sugar beet from closely related strains, thereby providing necessary information for further epidemiological work seeking to identify insect vectors and reservoir plant hosts. The results of this study indicate that there are differences in hybrid susceptibility. Clarifying the etiology of RTD as a long-known and economically important disease is certainly the first step toward disease management in Serbia and neighboring countries.
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Affiliation(s)
- Živko Ćurčić
- Institute of Field and Vegetable Crops, Novi Sad 21000, Serbia
| | - Jelena Stepanović
- Institute of Pesticides and Environmental Protection, Belgrade 11080, Serbia
| | - Christina Zübert
- University of Hohenheim, Integrative Infection Biology Crops-Livestock, Stuttgart 70599, Germany
| | | | - Andrea Kosovac
- Institute of Pesticides and Environmental Protection, Belgrade 11080, Serbia
| | - Emil Rekanović
- Institute of Pesticides and Environmental Protection, Belgrade 11080, Serbia
| | - Michael Kube
- University of Hohenheim, Integrative Infection Biology Crops-Livestock, Stuttgart 70599, Germany
| | - Bojan Duduk
- Institute of Pesticides and Environmental Protection, Belgrade 11080, Serbia
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Multilocus Genotyping Reveals New Molecular Markers for Differentiating Distinct Genetic Lineages among " Candidatus Phytoplasma Solani" Strains Associated with Grapevine Bois Noir. Pathogens 2020; 9:pathogens9110970. [PMID: 33233322 PMCID: PMC7700334 DOI: 10.3390/pathogens9110970] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 11/18/2020] [Accepted: 11/19/2020] [Indexed: 11/16/2022] Open
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.
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20
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Conigliaro G, Jamshidi E, Lo Verde G, Bella P, Mondello V, Giambra S, D’Urso V, Tsolakis H, Murolo S, Burruano S, Romanazzi G. Epidemiological Investigations and Molecular Characterization of ' Candidatus Phytoplasma solani' in Grapevines, Weeds, Vectors and Putative Vectors in Western Sicily, (Southern Italy). Pathogens 2020; 9:pathogens9110918. [PMID: 33171934 PMCID: PMC7694634 DOI: 10.3390/pathogens9110918] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 10/29/2020] [Accepted: 11/02/2020] [Indexed: 01/07/2023] Open
Abstract
Bois noir is caused by 'Candidatus Phytoplasma solani', and it is one of the most important and widespread diseases in the Euro-Mediterranean region. There are complex interactions between phytoplasma and grapevines, weeds, and vectors. These ecological relationships can be tracked according to molecular epidemiology. The aims of the 2-year study (2014-2015) were to describe incidence and spatial distribution of Bois noir in a vineyard with three grapevine varieties in Sicily, and to identify the molecular types of the tuf and vmp1 genes in these naturally infected grapevines, according to the potential reservoir plants and vectors. Disease incidence in 2015 was significantly higher in 'Chardonnay' (up to 35%) than for 'Nero d'Avola' and 'Pinot noir' (<5%). All grapevine, weed, and insect samples were infected by 'Ca. P. solani' tuf-type b. Most of the collected insects were strictly related to Vitis spp. and belonged to Neoaliturus fenestratus, Empoasca spp., and Zygina rhamni. The characterization of the vmp1 gene revealed six different vmp types in grapevines (V1, V4, V9, V11, V12, V24), three in weeds (V4, V9, V11), and four in insects (V4, V9, V11, V24). Notably, V4, V9, appear both in hosts and vectors, with V9 predominant. Virtual restriction fragment length polymorphism (RFLP) analysis based on the nucleotide sequences supported the data of the conventional RFLP. Connections between the molecular data recorded in the vineyard ecosystems and the application of innovative tools based on the geostatistical analysis will contribute to further clarification of the specific ecological and epidemiological aspects of 'Ca. P. solani' in Sicily.
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Affiliation(s)
- Gaetano Conigliaro
- Dipartimento di Scienze Agrarie, Alimentari e Forestali, Università degli Studi di Palermo, Viale delle Scienze Ed. 4, 90128 Palermo, Italy; (G.C.); (G.L.V.); (P.B.); (S.G.); (H.T.); (S.B.)
| | - Elham Jamshidi
- Department of Agricultural, Food and Environmental Science, Marche Polytechnic University, 60131 Ancona, Italy; (E.J.); (S.M.)
| | - Gabriella Lo Verde
- Dipartimento di Scienze Agrarie, Alimentari e Forestali, Università degli Studi di Palermo, Viale delle Scienze Ed. 4, 90128 Palermo, Italy; (G.C.); (G.L.V.); (P.B.); (S.G.); (H.T.); (S.B.)
| | - Patrizia Bella
- Dipartimento di Scienze Agrarie, Alimentari e Forestali, Università degli Studi di Palermo, Viale delle Scienze Ed. 4, 90128 Palermo, Italy; (G.C.); (G.L.V.); (P.B.); (S.G.); (H.T.); (S.B.)
| | - Vincenzo Mondello
- Résistance Induite et Bioprotection des Plantes (RIBP), SFR Condorcet FR CNRS 3417, Université de Reims Champagne-Ardenne, EA 4707, BP 1039, CEDEX 2, 51687 Reims, France;
| | - Selene Giambra
- Dipartimento di Scienze Agrarie, Alimentari e Forestali, Università degli Studi di Palermo, Viale delle Scienze Ed. 4, 90128 Palermo, Italy; (G.C.); (G.L.V.); (P.B.); (S.G.); (H.T.); (S.B.)
| | - Vera D’Urso
- Sezione di Biologia Animale, Dipartimento di Scienze Biologiche, Geologiche e Ambientali, Università degli Studi di Catania, via Androne 81, 95124 Catania, Italy;
| | - Haralabos Tsolakis
- Dipartimento di Scienze Agrarie, Alimentari e Forestali, Università degli Studi di Palermo, Viale delle Scienze Ed. 4, 90128 Palermo, Italy; (G.C.); (G.L.V.); (P.B.); (S.G.); (H.T.); (S.B.)
| | - Sergio Murolo
- Department of Agricultural, Food and Environmental Science, Marche Polytechnic University, 60131 Ancona, Italy; (E.J.); (S.M.)
| | - Santella Burruano
- Dipartimento di Scienze Agrarie, Alimentari e Forestali, Università degli Studi di Palermo, Viale delle Scienze Ed. 4, 90128 Palermo, Italy; (G.C.); (G.L.V.); (P.B.); (S.G.); (H.T.); (S.B.)
| | - Gianfranco Romanazzi
- Department of Agricultural, Food and Environmental Science, Marche Polytechnic University, 60131 Ancona, Italy; (E.J.); (S.M.)
- Correspondence: ; Tel.: +39-071-2204336
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Relationships between Hyalesthes obsoletus, Its Herbaceous Hosts and Bois Noir Epidemiology in Northern Italian Vineyards. INSECTS 2020; 11:insects11090606. [PMID: 32906774 PMCID: PMC7565731 DOI: 10.3390/insects11090606] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/25/2020] [Accepted: 09/03/2020] [Indexed: 11/17/2022]
Abstract
Hyalesthes obsoletus is the vector of "Candidatus Phytoplasma (Ca. P.) solani," the causal agent of grapevine yellows Bois noir (BN). The relationships among the planthopper, its main herbaceous hosts as phytoplasma reservoirs (Convolvolus arvensis and Urtica dioica) and BN spreading were studied in northern Italy. In two areas the relationship between host plants and the phenology and survival of planthopper adults was investigated in potted plants and in field conditions. Moreover, H. obsoletus ecology, newly symptomatic grapevine occurrence and "Ca. P. solani" tuf-types' presence were studied in two vineyards (2014-2019). An earlier occurrence of H. obsoletus adults on C. arvensis than U. dioica and better adult survival of the originating host were observed. When U. dioica was prevalent, the vector occurred almost exclusively along the ditch outside the vineyard. Hyalesthes obsoletus amount varied widely from year to year and nymphal mortality due to late frosts was supposed. In one vineyard, the amount of newly symptomatic grapevines was significantly correlated with vector abundance in the previous year. The "Ca. P. solani" tuf-type was influenced by vector population levels on the two hosts. Since the abundance of H. obsoletus populations on the two hosts influences BN epidemiology and dynamics and the "Ca. P. solani" tuf-type, this must be considered in BN control strategies.
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Jamshidi E, Murolo S, Salehi M, Romanazzi G. Sequence Analysis of New Tuf Molecular Types of ' Candidatus Phytoplasma Solani' in Iranian Vineyards. Pathogens 2020; 9:pathogens9060508. [PMID: 32599831 PMCID: PMC7350298 DOI: 10.3390/pathogens9060508] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 06/11/2020] [Accepted: 06/17/2020] [Indexed: 12/26/2022] Open
Abstract
Grapevine Bois noir (BN) is caused by ‘Candidatus Phytoplasma solani’ (‘Ca. P. solani’) and is one of the most important phytoplasma diseases in the Euro-Mediterranean viticultural areas. The epidemiology of BN can include grapevine as a plant host and is usually transmitted via sap-sucking insects that inhabit herbaceous host plants. Tracking the spread of ‘Ca. P. solani’ strains is of great help for the identification of plant reservoirs and insect vectors involved in local BN outbreaks. The molecular epidemiology of ‘Ca. P. solani’ is primarily based on sequence analysis of the tuf housekeeping gene (which encodes elongation factor Tu). In this study, molecular typing of tuf, through restriction fragment length polymorphism and sequencing, was carried out on grapevine samples from Iranian vineyards. According to the molecular characterization, three molecular types—tuf b1, tuf b5 and tuf b6—were found, with tuf b1 being the most prominent. These data provide further knowledge of tuf gene diversity and question the ecological role of such “minor” tuf types in Iranian vineyards, which have been detected only in grapevines.
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Affiliation(s)
- Elham Jamshidi
- Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, 60131 Ancona, Italy; (E.J.); (S.M.)
| | - Sergio Murolo
- Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, 60131 Ancona, Italy; (E.J.); (S.M.)
| | - Mohammad Salehi
- Plant Protection Research Department, Fars Agricultural and Natural Resources Research and Education Centre, AREEO, Zarghan 617-71555, Iran;
| | - Gianfranco Romanazzi
- Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, 60131 Ancona, Italy; (E.J.); (S.M.)
- Correspondence: ; Tel.: +39-071-220-4336
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Girsova N, Aleinikova N, Kastalyeva T, Radionovskaya Y, Bogoutdinov D. Phytoplasma disease “Bois noir” in Crimea: diagnosis of the pathogen. BIO WEB OF CONFERENCES 2020. [DOI: 10.1051/bioconf/20202506004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
In 2018-2019, grape leaf samples with symptoms of yellowing (reddening) and leaf rolling collected from grapevines of different regions of Crimea were tested for the presence of phytoplasma using the “nested”PCR with primer pairs P1/16S-Sr and R16F2n/R16R2. Phytoplasmas were detected in 91% grape samples of 2018 and 46% samples of 2019. Genotyping performed by restriction fragment length polymorphism analysis for three genes: ribosomal (16S rRNA), the tuf gene encoding the elongation factor EF-Tu, and the vmp1 gene encoding a membrane protein, showed that the phytoplasmas isolated from all samples were related to the species Candidatus Phytoplasma solani, type “b”. Polymorphism was observed only for the vmp1 gene. The electrophoretic profiles of grape phytoplasma of 2018 (‘Chardonnay’ variety) differed from those of grape phytoplasma of 2019 (‘Pinot Noir’ and ‘Verdelho’ varieties), as well as from the profiles published in well-known works, which indicates the genetic diversity.
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Quaglino F, Sanna F, Moussa A, Faccincani M, Passera A, Casati P, Bianco PA, Mori N. Identification and ecology of alternative insect vectors of 'Candidatus Phytoplasma solani' to grapevine. Sci Rep 2019; 9:19522. [PMID: 31862945 PMCID: PMC6925216 DOI: 10.1038/s41598-019-56076-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 11/28/2019] [Indexed: 11/08/2022] Open
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.
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Affiliation(s)
- Fabio Quaglino
- Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia, Università degli Studi di Milano, via Celoria 2, 20133, Milano, Italy
| | - Francesco Sanna
- Dipartimento di Agronomia Animali Alimenti Risorse Naturali e Ambiente, Università degli Studi di Padova, Agripolis - viale dell'università, 16 - Legnaro, Padova, Italy
| | - Abdelhameed Moussa
- Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia, Università degli Studi di Milano, via Celoria 2, 20133, Milano, Italy
| | - Monica Faccincani
- Consorzio per la tutela del Franciacorta - via G. Verdi 53, 25030, Erbusco, BS, Italy
| | - Alessandro Passera
- Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia, Università degli Studi di Milano, via Celoria 2, 20133, Milano, Italy
| | - Paola Casati
- Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia, Università degli Studi di Milano, via Celoria 2, 20133, Milano, Italy
| | - Piero Attilio Bianco
- Dipartimento di Scienze Agrarie e Ambientali - Produzione, Territorio, Agroenergia, Università degli Studi di Milano, via Celoria 2, 20133, Milano, Italy
| | - Nicola Mori
- Dipartimento di Agronomia Animali Alimenti Risorse Naturali e Ambiente, Università degli Studi di Padova, Agripolis - viale dell'università, 16 - Legnaro, Padova, Italy.
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Jamshidi E, Murolo S, Ravari SB, Salehi M, Romanazzi G. Molecular Typing of ' Candidatus Phytoplasma solani' in Iranian Vineyards. PLANT DISEASE 2019; 103:2412-2416. [PMID: 31306091 DOI: 10.1094/pdis-02-19-0281-re] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Grapevine (Vitis vinifera L.) is one of the most important horticultural crops in Iran, with >200,000 ha of cultivated area. Recently, outbreaks of the grapevine yellows Bois noir that is associated with phytoplasma strains related to 'Candidatus Phytoplasma solani' were recorded in several Iranian regions. This has resulted in severe economic losses. We carried out a survey in 2015, followed by collection of leaf samples from symptomatic grapevines and weeds. Because no information is available on the molecular epidemiology of 'Ca. P. solani' in Iran, multiple gene analyses were carried out here according to molecular characterization of the tuf and vmp1 genes. From the molecular characterization, all of the samples (i.e., grapevines, weeds) were infected with tuf b type. Detailed molecular characterization of the vmp1 gene (i.e., PCR-restriction fragment length polymorphism, sequence analysis) defined five molecular types: V1, V4, V10, V15, and V20. The abundance of Convolvulus arvensis in vineyards and detection of the same 'Ca. P. solani' molecular types in grapevines and weeds suggest that C. arvensis has a major role in Bois noir epidemiology of Iranian vineyards. Therefore, control strategies should be developed to manage these host plants to reduce inoculum sources of the phytoplasma in vineyards.
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Affiliation(s)
- Elham Jamshidi
- Plant Protection Department, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Sergio Murolo
- Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, Ancona, Italy
| | | | - Mohammad Salehi
- Plant Protection Research Department, Fars Agricultural and Natural Resources Research and Education Centre, AREEO, Zarghan, Iran
| | - Gianfranco Romanazzi
- Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, Ancona, Italy
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Landi L, Murolo S, Romanazzi G. Detection of 'Candidatus Phytoplasma solani' in roots from Bois noir symptomatic and recovered grapevines. Sci Rep 2019; 9:2013. [PMID: 30765733 PMCID: PMC6375969 DOI: 10.1038/s41598-018-38135-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 12/17/2018] [Indexed: 12/12/2022] Open
Abstract
'Candidatus Phytoplasma solani' is the causal agent of Bois noir (BN) in grapevine (Vitis vinifera). It is usually detected in leaves, where typical disease symptoms are seen. However, little information is available on the presence of this phytoplasma in grapevine roots. Here, we investigated 'Ca. P. solani' in roots collected from 28 symptomatic, 27 recovered and eight asymptomatic grapevine plants. Protocols based on high-resolution melting (HRM) combined with real-time quantitative PCR (qPCR-HRM) and nested-qPCR-HRM were developed to identify 'Ca. P. solani' tuf-type variants with single nucleotide polymorphisms. In all, 21.4% of roots from symptomatic plants were positive to 'Ca. P. solani' using qPCR-HRM, and 60.7% with nested-qPCR HRM. Also, 7.4% of roots from recovered plants were positive using qPCR-HRM, which reached 44.4% using nested-qPCR HRM. These analyses identified tuf-type b1 on 88.2% of the positive samples from symptomatic grapevines, and 66.6% from recovered grapevines, with all other samples identified as tuf-type a. This study reports the presence of 'Ca. P. solani' in the roots of both symptomatic and recovered grapevines. These qPCR-HRM and nested-qPCR-HRM protocols can be applied to increase the sensitivity of detection of, and to simplify and speed up the screening for, 'Ca. P. solani' tuf-types.
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Affiliation(s)
- Lucia Landi
- Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, Via Brecce Bianche, I-60131, Ancona, Italy
| | - Sergio Murolo
- Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, Via Brecce Bianche, I-60131, Ancona, Italy
| | - Gianfranco Romanazzi
- Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, Via Brecce Bianche, I-60131, Ancona, Italy.
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Lavender Decline in France Is Associated with Chronic Infection by Lavender-Specific Strains of "Candidatus Phytoplasma solani". Appl Environ Microbiol 2018; 84:AEM.01507-18. [PMID: 30291116 PMCID: PMC6275342 DOI: 10.1128/aem.01507-18] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 09/04/2018] [Indexed: 11/20/2022] Open
Abstract
The etiology and main pathways for the spread of lavender decline, an infectious disease affecting French lavender production since the 1960s, have remained unclear, hampering the development of efficient control strategies. An extensive survey of lavender fields led to the conclusion that “Candidatus Phytoplasma solani” was chronically infecting declining lavenders and was associated with large infectious populations of Hyalesthes obsoletus planthoppers living on the crop itself. Lavender appeared to be the main reservoir host for lavender-specific phytoplasma strains, an unusual feature for this phytoplasma, which usually propagates from reservoir weeds to various economically important crops. These results point out the necessity to protect young lavender fields from the initial phytoplasma inoculum coming from surrounding lavender fields or from infected nurseries and to promote agricultural practices that reduce the development of H. obsoletus vector populations. Lavender decline compromises French lavender production, and preliminary data have suggested the involvement of “Candidatus Phytoplasma solani” in the etiology of the disease. In order to evaluate the epidemiological role of “Ca. Phytoplasma solani,” a 3-year survey was conducted in southeastern France. “Ca. Phytoplasma solani” was detected in 19 to 56% of the declining plants, depending on seasons and cultivars, and its prevalence was correlated with symptom severity. Autumn was more favorable than spring for phytoplasma detection, and “Ca. Phytoplasma solani” incidence was higher in Lavandula angustifolia than in Lavandula intermedia hybrids. Detection of the phytoplasma fluctuated over months, supporting the chronicity of infection. Three “Ca. Phytoplasma solani” secY genotypes, S17, S16, and S14, were the most prevalent in lavender fields and were also detected in nurseries, whereas strains detected in surrounding bindweed and wild carrots were mostly of the S1 and S4 genotypes. This suggests that lavender is the main pathogen reservoir of the epidemic. Adults and nymphs of the planthopper vector Hyalesthes obsoletus were commonly captured in lavender fields and were shown to harbor mainly the prevalent phytoplasma genotypes detected in lavenders. The “Ca. Phytoplasma solani” genotype S17 was transmitted to Catharanthus roseus periwinkle by naturally infected H. obsoletus. Finally, the inventory of the bacterial community of declining lavenders that tested negative for “Ca. Phytoplasma solani” by 16S rRNA deep sequencing ruled out the involvement of other phloem-limited bacterial pathogens. IMPORTANCE The etiology and main pathways for the spread of lavender decline, an infectious disease affecting French lavender production since the 1960s, have remained unclear, hampering the development of efficient control strategies. An extensive survey of lavender fields led to the conclusion that “Candidatus Phytoplasma solani” was chronically infecting declining lavenders and was associated with large infectious populations of Hyalesthes obsoletus planthoppers living on the crop itself. Lavender appeared to be the main reservoir host for lavender-specific phytoplasma strains, an unusual feature for this phytoplasma, which usually propagates from reservoir weeds to various economically important crops. These results point out the necessity to protect young lavender fields from the initial phytoplasma inoculum coming from surrounding lavender fields or from infected nurseries and to promote agricultural practices that reduce the development of H. obsoletus vector populations.
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Widespread plant specialization in the polyphagous planthopper Hyalesthes obsoletus (Cixiidae), a major vector of stolbur phytoplasma: Evidence of cryptic speciation. PLoS One 2018; 13:e0196969. [PMID: 29738577 PMCID: PMC5940214 DOI: 10.1371/journal.pone.0196969] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 04/24/2018] [Indexed: 11/22/2022] Open
Abstract
The stolbur phytoplasma vector Hyalesthes obsoletus is generally considered as a polyphagous species associated with numerous wild and cultivated plants. However, recent research in southeastern Europe, the distribution centre of H. obsoletus and the area of most stolbur-inflicted crop diseases, points toward specific host-plant associations of the vector, indicating specific vector-based transmission routes. Here, we study the specificity of populations associated with four host-plants using mitochondrial and nuclear genetic markers, and we evaluate the evolution of host-shifts in H. obsoletus. Host-plant use was confirmed for Convolvulus arvensis, Urtica dioica, Vitex agnus-castus and Crepis foetida. Mitochondrial genetic analysis showed sympatric occurrence of three phylogenetic lineages that were ecologically delineated by host-plant preference, but were morphologically inseparable. Nuclear data supported the existence of three genetic groups (Evanno’s ΔK(3) = 803.72) with average genetic membership probabilities > 90%. While populations associated with C. arvensis and U. dioica form a homogenous group, populations affiliated with V. agnus-castus and C. foetida constitute two independent plant-associated lineages. The geographical signal permeating the surveyed populations indicated complex diversification processes associated with host-plant selection and likely derived from post-glacial refugia in the eastern Mediterranean. This study provides evidence for cryptic species diversification within H. obsoletus sensu lato: i) consistent mitochondrial differentiation (1.1–1.5%) among host-associated populations in syntopy and in geographically distant areas, ii) nuclear genetic variance supporting mitochondrial data, and iii) average mitochondrial genetic distances among host-associated meta-populations are comparable to the most closely related, morphologically distinguishable species, i.e., Hyalesthes thracicus (2.1–3.3%).
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Pierro R, Passera A, Panattoni A, Casati P, Luvisi A, Rizzo D, Bianco PA, Quaglino F, Materazzi A. 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'. PHYTOPATHOLOGY 2018; 108:362-373. [PMID: 29027886 DOI: 10.1094/phyto-06-17-0215-r] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
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.
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Affiliation(s)
- R Pierro
- First, third, fifth, and ninth authors: Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy; second, fourth, seventh, and eighth authors: Department of Agricultural and Environmental Sciences-Production, Landscape, Agroenergy, University of Milan, via Celoria 2, 20133 Milano, Italy; fifth author: Department of Biological and Environmental Sciences and Technologies-University of Salento, via Provinciale Monteroni, 73100 Lecce, Italy; and sixth author: Regional Phytosanitary Service, Laboratory of Phytopathological Diagnostics and Molecular Biology, via Ciliegiole 99, 51100 Pistoia, Italy
| | - A Passera
- First, third, fifth, and ninth authors: Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy; second, fourth, seventh, and eighth authors: Department of Agricultural and Environmental Sciences-Production, Landscape, Agroenergy, University of Milan, via Celoria 2, 20133 Milano, Italy; fifth author: Department of Biological and Environmental Sciences and Technologies-University of Salento, via Provinciale Monteroni, 73100 Lecce, Italy; and sixth author: Regional Phytosanitary Service, Laboratory of Phytopathological Diagnostics and Molecular Biology, via Ciliegiole 99, 51100 Pistoia, Italy
| | - A Panattoni
- First, third, fifth, and ninth authors: Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy; second, fourth, seventh, and eighth authors: Department of Agricultural and Environmental Sciences-Production, Landscape, Agroenergy, University of Milan, via Celoria 2, 20133 Milano, Italy; fifth author: Department of Biological and Environmental Sciences and Technologies-University of Salento, via Provinciale Monteroni, 73100 Lecce, Italy; and sixth author: Regional Phytosanitary Service, Laboratory of Phytopathological Diagnostics and Molecular Biology, via Ciliegiole 99, 51100 Pistoia, Italy
| | - P Casati
- First, third, fifth, and ninth authors: Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy; second, fourth, seventh, and eighth authors: Department of Agricultural and Environmental Sciences-Production, Landscape, Agroenergy, University of Milan, via Celoria 2, 20133 Milano, Italy; fifth author: Department of Biological and Environmental Sciences and Technologies-University of Salento, via Provinciale Monteroni, 73100 Lecce, Italy; and sixth author: Regional Phytosanitary Service, Laboratory of Phytopathological Diagnostics and Molecular Biology, via Ciliegiole 99, 51100 Pistoia, Italy
| | - A Luvisi
- First, third, fifth, and ninth authors: Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy; second, fourth, seventh, and eighth authors: Department of Agricultural and Environmental Sciences-Production, Landscape, Agroenergy, University of Milan, via Celoria 2, 20133 Milano, Italy; fifth author: Department of Biological and Environmental Sciences and Technologies-University of Salento, via Provinciale Monteroni, 73100 Lecce, Italy; and sixth author: Regional Phytosanitary Service, Laboratory of Phytopathological Diagnostics and Molecular Biology, via Ciliegiole 99, 51100 Pistoia, Italy
| | - D Rizzo
- First, third, fifth, and ninth authors: Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy; second, fourth, seventh, and eighth authors: Department of Agricultural and Environmental Sciences-Production, Landscape, Agroenergy, University of Milan, via Celoria 2, 20133 Milano, Italy; fifth author: Department of Biological and Environmental Sciences and Technologies-University of Salento, via Provinciale Monteroni, 73100 Lecce, Italy; and sixth author: Regional Phytosanitary Service, Laboratory of Phytopathological Diagnostics and Molecular Biology, via Ciliegiole 99, 51100 Pistoia, Italy
| | - P A Bianco
- First, third, fifth, and ninth authors: Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy; second, fourth, seventh, and eighth authors: Department of Agricultural and Environmental Sciences-Production, Landscape, Agroenergy, University of Milan, via Celoria 2, 20133 Milano, Italy; fifth author: Department of Biological and Environmental Sciences and Technologies-University of Salento, via Provinciale Monteroni, 73100 Lecce, Italy; and sixth author: Regional Phytosanitary Service, Laboratory of Phytopathological Diagnostics and Molecular Biology, via Ciliegiole 99, 51100 Pistoia, Italy
| | - F Quaglino
- First, third, fifth, and ninth authors: Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy; second, fourth, seventh, and eighth authors: Department of Agricultural and Environmental Sciences-Production, Landscape, Agroenergy, University of Milan, via Celoria 2, 20133 Milano, Italy; fifth author: Department of Biological and Environmental Sciences and Technologies-University of Salento, via Provinciale Monteroni, 73100 Lecce, Italy; and sixth author: Regional Phytosanitary Service, Laboratory of Phytopathological Diagnostics and Molecular Biology, via Ciliegiole 99, 51100 Pistoia, Italy
| | - A Materazzi
- First, third, fifth, and ninth authors: Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124 Pisa, Italy; second, fourth, seventh, and eighth authors: Department of Agricultural and Environmental Sciences-Production, Landscape, Agroenergy, University of Milan, via Celoria 2, 20133 Milano, Italy; fifth author: Department of Biological and Environmental Sciences and Technologies-University of Salento, via Provinciale Monteroni, 73100 Lecce, Italy; and sixth author: Regional Phytosanitary Service, Laboratory of Phytopathological Diagnostics and Molecular Biology, via Ciliegiole 99, 51100 Pistoia, Italy
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Marasco R, Rolli E, Fusi M, Michoud G, Daffonchio D. Grapevine rootstocks shape underground bacterial microbiome and networking but not potential functionality. MICROBIOME 2018; 6:3. [PMID: 29298729 PMCID: PMC5751889 DOI: 10.1186/s40168-017-0391-2] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 12/18/2017] [Indexed: 05/09/2023]
Abstract
BACKGROUND The plant compartments of Vitis vinifera, including the rhizosphere, rhizoplane, root endosphere, phyllosphere and carposphere, provide unique niches that drive specific bacterial microbiome associations. The majority of phyllosphere endophytes originate from the soil and migrate up to the aerial compartments through the root endosphere. Thus, the soil and root endosphere partially define the aerial endosphere in the leaves and berries, contributing to the terroir of the fruit. However, V. vinifera cultivars are invariably grafted onto the rootstocks of other Vitis species and hybrids. It has been hypothesized that the plant species determines the microbiome of the root endosphere and, as a consequence, the aerial endosphere. In this work, we test the first part of this hypothesis. We investigate whether different rootstocks influence the bacteria selected from the surrounding soil, affecting the bacterial diversity and potential functionality of the rhizosphere and root endosphere. METHODS Bacterial microbiomes from both the root tissues and the rhizosphere of Barbera cultivars, both ungrafted and grafted on four different rootstocks, cultivated in the same soil from the same vineyard, were characterized by 16S rRNA high-throughput sequencing. To assess the influence of the root genotype on the bacterial communities' recruitment in the root system, (i) the phylogenetic diversity coupled with the predicted functional profiles and (ii) the co-occurrence bacterial networks were determined. Cultivation-dependent approaches were used to reveal the plant-growth promoting (PGP) potential associated with the grafted and ungrafted root systems. RESULTS Richness, diversity and bacterial community networking in the root compartments were significantly influenced by the rootstocks. Complementary to a shared bacterial microbiome, different subsets of soil bacteria, including those endowed with PGP traits, were selected by the root system compartments of different rootstocks. The interaction between the root compartments and the rootstock exerted a unique selective pressure that enhanced niche differentiation, but rootstock-specific bacterial communities were still recruited with conserved PGP traits. CONCLUSION While the rootstock significantly influences the taxonomy, structure and network properties of the bacterial community in grapevine roots, a homeostatic effect on the distribution of the predicted and potential functional PGP traits was found.
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Affiliation(s)
- Ramona Marasco
- King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering Division (BESE), Thuwal, 23955-6900, Saudi Arabia.
| | - Eleonora Rolli
- Department of Food Environmental and Nutritional Sciences, Università degli Studi di Milano, 20133, Milano, Italy
| | - Marco Fusi
- King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering Division (BESE), Thuwal, 23955-6900, Saudi Arabia
| | - Grégoire Michoud
- King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering Division (BESE), Thuwal, 23955-6900, Saudi Arabia
| | - Daniele Daffonchio
- King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering Division (BESE), Thuwal, 23955-6900, Saudi Arabia.
- Department of Food Environmental and Nutritional Sciences, Università degli Studi di Milano, 20133, Milano, Italy.
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Quaglino F, Maghradze D, Casati P, Chkhaidze N, Lobjanidze M, Ravasio A, Passera A, Venturini G, Failla O, Bianco PA. 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. PLANT DISEASE 2016; 100:904-915. [PMID: 30686148 DOI: 10.1094/pdis-09-15-0978-re] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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.
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Affiliation(s)
- Fabio Quaglino
- Department of Agricultural and Environmental Sciences-Production, Landscape, Agroenergy (DISAA), University of Milan, Milano, Italy
| | - David Maghradze
- Institute of Horticulture, Viticulture and Oenology, Agricultural University of Georgia, Tbilisi, Georgia
| | | | - Nona Chkhaidze
- Laboratory of Plant Anatomy and Physiology, Agricultural University of Georgia, Tbilisi
| | - Mzagho Lobjanidze
- Institute of Entomology, Agricultural University of Georgia, Tbilisi
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Murolo S, Romanazzi G. In-vineyard population structure of 'Candidatus Phytoplasma solani' using multilocus sequence typing analysis. INFECTION GENETICS AND EVOLUTION 2015; 31:221-30. [PMID: 25660034 DOI: 10.1016/j.meegid.2015.01.028] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2014] [Revised: 01/28/2015] [Accepted: 01/29/2015] [Indexed: 11/28/2022]
Abstract
'Candidatus Phytoplasma solani' is a phytoplasma of the stolbur group (16SrXII subgroup A) that is associated with 'Bois noir' and causes heavy damage to the quality and quantity of grapevine yields in several European countries, and particularly in the Mediterranean area. Analysis of 'Ca. P. solani' genetic diversity was carried out for strains infecting a cv. 'Chardonnay' vineyard, through multilocus sequence typing analysis for the vmp1, stamp and secY genes. Several types per gene were detected: seven out of 20 types for vmp1, six out of 17 for stamp, and four out of 16 for secY. High correlations were seen among the vmp1, stamp and secY typing with the tuf typing. However, no correlations were seen among the tuf and vmp1 types and the Bois noir severity in the surveyed grapevines. Grouping the 'Ca. P. solani' sequences on the basis of their origins (i.e., study vineyard, Italian regions, Euro-Mediterranean countries), dN/dS ratio analysis revealed overall positive selection for stamp (3.99, P=0.019) and vmp1 (2.28, P=0.001). For secY, the dN/dS ratio was 1.02 (P=0.841), showing neutral selection across this gene. Using analysis of the nucleotide sequencing by a Bayesian approach, we determined the population structure of 'Ca. P. solani', which appears to be structured in 3, 5 and 6 subpopulations, according to the secY, stamp and vmp1 genes, respectively. The high genetic diversity of 'Ca. P. solani' from a single vineyard reflects the population structure across wider geographical scales. This information is useful to trace inoculum source and movement of pathogen strains at the local level and over long distances.
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Affiliation(s)
- Sergio Murolo
- Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, Ancona, Italy
| | - Gianfranco Romanazzi
- Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, Ancona, Italy.
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