title: Biological and molecular variability among geographically diverse isolates of sweet potato virus 2.
abstract: Sweet potato virus 2 (SPV2) is a tentative member of the genus Potyvirus, family Potyviridae. In addition to the type isolate of SPV2 recently characterised in greater detail, twelve additional isolates of this virus were obtained from sweet potato clones originating from China, Portugal, South Africa and Zambia. Sequences of the coat protein (CP) gene and 3' non-translated region (NTR) were determined. Comparisons of the CP gene sequences of these isolates revealed nucleotide and amino acid sequence identities ranging from 81 to 99% and from 86 to 99%, respectively. Phylogenetic analysis of sequences distinguished several groups, which partially correlated with the geographic origin of the isolates, and indicated that some isolates from South Africa and a Zambian isolate are most distinct both in CP and 3'NTR sequences. Host range studies of a selected number of isolates revealed some differences in test plant reactions, which appeared to correlate to some extent with the geographic origin and molecular distinctness of the SPV2 isolates. The results strongly suggest the occurrence of biologically and genetically diverse strains of SPV2.
authors.affiliation: Institute of Plant Virology, Microbiology and Biosafety, Biologische Bundesanstalt für Land- und Forstwirtschaft (BBA), Braunschweig, Germany.
authors.forename: E M
authors.initials: EM
authors.lastname: Ateka
authors.forename: E
authors.initials: E
authors.lastname: Barg
authors.forename: R W
authors.initials: RW
authors.lastname: Njeru
authors.forename: G
authors.initials: G
authors.lastname: Thompson
authors.forename: H J
authors.initials: HJ
authors.lastname: Vetten
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D004279:DNA, Viral / Q000235:genetics; D005843:Geography; D027723:Ipomoea batatas / Q000821:virology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D017800:Potyvirus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D012367:RNA, Viral / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D014764:Viral Proteins / Q000235:genetics
chemical_list: D004279:DNA, Viral; D012367:RNA, Viral; D014764:Viral Proteins