title: The genetic diversity of Citrus dwarfing viroid populations is mainly dependent on the infected host species.
abstract: As with viruses, viroids infect their hosts as polymorphic populations of variants. Identifying possible sources of genetic variability is significant in the case of the species Citrus dwarfing viroid (CDVd) which has been proposed as a dwarfing agent for high-density citrus plantings. Here, a natural CDVd isolate (CMC) was used as an inoculum source for long-term (25 years) and short-term (1 year) bioassays in different citrus host species. Characterization of progenies indicated that the genetic stability of CDVd populations was high in certain hosts (trifoliate orange, Troyer citrange, Etrog citron, Navelina sweet orange), which preserve viroid populations similar to the original CMC isolate even after 25 years. By contrast, CDVd variant populations in Interdonato lemon and Volkamer lemon were completely different to those in the inoculated sources, highlighting how influential the host is on the genetic variability of CDVd populations. Implications for risk assessment of CDVd as a dwarfing agent are discussed. The GenBank/EMBL/DDBJ accession numbers for the complete sequences of the Citrus dwarfing viroid variants are JF970266.1 forH2-2, JF970267.1 for H2-7, EU938647.1 for H6-2, EU938651.1 forH6-10, JF970268.1 for H10-7, EU938652.1 for H14-13, EU938653.1for H14-14, JF970269.1 for H14-16, EU938648.1 for H15-9,EU938649.1 for H16-2, JF970265.1 for H16-9, EU938654.1 forH16-13, EU938650.1 for H20-3, JF970270.1 for H20-7, EU938641.1for PR-1, EU938642.1 for PR-3, EU938643.1 for PR-7, EU938644.1for CR-1, EU938639.1 for VR-4, JF12070.1 for VR-15, JF812069.1LS-4, EU938640.1 for LS-10 and JF970264.1 for LS-11.
authors.affiliation: Dipartimento di Scienze delle Produzioni Agrarie e Alimentari - Sez. Fitopatologia e Genetica agraria, Università di Catania, 95123 Catania, Italy.
authors.forename: Matilde
authors.initials: M
authors.lastname: Tessitori
authors.affiliation: Dipartimento di Scienze delle Produzioni Agrarie e Alimentari - Sez. Fitopatologia e Genetica agraria, Università di Catania, 95123 Catania, Italy.
authors.forename: Serena
authors.initials: S
authors.lastname: Rizza
authors.affiliation: Dipartimento di Scienze delle Produzioni Agrarie e Alimentari - Sez. Fitopatologia e Genetica agraria, Università di Catania, 95123 Catania, Italy.
authors.forename: Antonella
authors.initials: A
authors.lastname: Reina
authors.affiliation: Dipartimento di Scienze delle Produzioni Agrarie e Alimentari - Sez. Fitopatologia e Genetica agraria, Università di Catania, 95123 Catania, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Causarano
authors.affiliation: Istituto di Virologia Vegetale, UOS Bari, Consiglio Nazionale delle Ricerche, 70126 Bari, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Di Serio
mesh_terms: D001483:Base Sequence; D002957:Citrus / Q000821:virology*; D018076:DNA, Complementary / Q000235:genetics; D015967:Gene Expression Regulation, Viral / Q000502:physiology; D014644:Genetic Variation; D008969:Molecular Sequence Data; D010802:Phylogeny; D010935:Plant Diseases / Q000821:virology*; D010942:Plant Viruses / Q000235:genetics*; D012367:RNA, Viral / Q000235:genetics; D013045:Species Specificity
chemical_list: D018076:DNA, Complementary; D012367:RNA, Viral