title: Indian bunchy top disease of tomato plants is caused by a distinct strain of citrus exocortis viroid.
abstract: A viroid has been isolated from tomato plants affected by Indian bunchy top disease of tomato (Lycopersicon esculentum Mill.). In dot blot hybridization assays with 32P-labelled cRNA probes specific for the detection of various viroids, the Indian viroid was shown to be most closely related to the citrus exocortis viroid (CEVd). Sequence determination showed that the viroid consists of 372 nucleotides and confirmed its close relationship with CEVd. The viroid, for which we propose the acronym CEVd-t, differs from the Australian CEVd strains A and B by 36 and 47 nucleotides, respectively, and from the Spanish grapevine isolate by 52 changes. A phylogenetic analysis confirmed the closet relationship with CEVd in all structural domains, except the pathogenicity and left-terminal domains, which are closely related to the corresponding domains of the potato spindle tuber and tomato apical stunt viroids, respectively.
authors.affiliation: Advance Center for Plant Virus Education and Research, Indian Agricultural Research Institute, New Delhi.
authors.forename: M D
authors.initials: MD
authors.lastname: Mishra
authors.forename: R W
authors.initials: RW
authors.lastname: Hammond
authors.forename: R A
authors.initials: RA
authors.lastname: Owens
authors.forename: D R
authors.initials: DR
authors.lastname: Smith
authors.forename: T O
authors.initials: TO
authors.lastname: Diener
mesh_terms: D001483:Base Sequence; D004279:DNA, Viral; D004591:Electrophoresis, Polyacrylamide Gel; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D010802:Phylogeny; D010935:Plant Diseases; D010942:Plant Viruses / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D012367:RNA, Viral / Q000737:chemistry / Q000302:isolation & purification; D014772:Viroids / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D004279:DNA, Viral; D012367:RNA, Viral