title: Genetic Variability of Stolbur Phytoplasma in Hyalesthes obsoletus (Hemiptera: Cixiidae) and its Main Host Plants in Vineyard Agroecosystems.
abstract: Bois noir is an economically important grapevine yellows that is induced by 'Candidatus Phytoplasma solani' and principally vectored by the planthopper Hyalesthes obsoletus Signoret (Hemiptera: Cixiidae). This study explores the 'Ca. P. solani' genetic variability associated to the nettle-H. obsoletus and bindweed-H. obsoletus systems in vineyard agroecosystems of the central-eastern Italy. Molecular characterization of 'Ca. P. solani' isolates was carried out using polymerase chain reaction/restriction fragment length polymorphism to investigate the nonribosomal vmp1 gene. Seven phytoplasma vmp-types were detected among the host plants- and insect-associated field-collected samples. The vmp1 gene showed the highest polymorphism in the bindweed-H. obsoletus system, according to restriction fragment length polymorphism analysis, which is in agreement with nucleotide sequence analysis. Five vmp-types were associated with H. obsoletus from bindweed, of which one was solely restricted to planthoppers, with one genotype also in planthoppers from nettle. Type V12 was the most prevalent in both planthoppers and bindweed. H. obsoletus from nettle harbored three vmp-types, of which V3 was predominant. V3 was the only type detected for nettle. Our data demonstrate that planthoppers might have acquired some 'Ca. P. solani' profiles from other plant hosts before landing on nettle or bindweed. Overall, the different vmp1 gene rearrangements observed in these two plant hosts-H. obsoletus systems might represent different adaptations of the pathogen to the two host plants. Molecular information about the complex of vmp-types provides useful data for better understanding of Bois noir epidemiology in vineyard agroecosystem.
authors.affiliation: Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Landi
authors.affiliation: Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona, Italy. p.riolo@univpm.it.
authors.forename: Paola
authors.initials: P
authors.lastname: Riolo
authors.affiliation: Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona, Italy.
authors.forename: Sergio
authors.initials: S
authors.lastname: Murolo
authors.affiliation: Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona, Italy.
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Romanazzi
authors.affiliation: Servizio Fitosanitario Regionale, Agenzia Servizi Settore Agroalimentare delle Marche, Via Industria 1, 60027 Osimo Stazione (AN), Italy.
authors.forename: Sandro
authors.initials: S
authors.lastname: Nardi
authors.affiliation: Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona, Italy.
authors.forename: Nunzio
authors.initials: N
authors.lastname: Isidoro
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics*; D031254:Convolvulus / Q000382:microbiology*; D014644:Genetic Variation; D006430:Hemiptera / Q000382:microbiology*; D007558:Italy; D008969:Molecular Sequence Data; D010802:Phylogeny; D045582:Phytoplasma / Q000235:genetics / Q000502:physiology*; D010935:Plant Diseases / Q000382:microbiology; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D017422:Sequence Analysis, DNA; D026982:Urtica dioica / Q000382:microbiology*; D027843:Vitis / Q000382:microbiology
chemical_list: D001426:Bacterial Proteins
keywords: Convolvulus arvensis; Hyalesthes obsoletus; Urtica dioica; stolbur; vmp1 gene