title: Characterization of southern African isolates of maize streak virus: typing of three isolates by restriction mapping.
abstract: The genomic replicative form DNAs (RF-DNA) of three maize streak virus isolates (MSV-CT, MSV-PE, and MSV-SW) from widely separated locations in southern Africa were characterized by restriction endonuclease mapping in order to assess the feasibility of using the technique to determine genetic variability between isolates. The viruses were transmitted to and propagated in laboratory-grown maize by the leafhopper vector Cicadulina mbila (Naudé). MSV-PE produced more severe symptoms than MSV-CT and MSV-SW; the isolates were serologically identical in 'western' immunoblot tests, but distinct in 'sandwich' enzyme-linked immunosorbent assays. RF-DNA of all three isolates was prepared from infected maize; the RF-DNA of MSV-CT and MSV-PE was cloned in a plasmid vector in Escherichia coli. Restriction maps were generated from this cloned DNA and from the RF-DNA of MSV-SWA. The maps were similar in regions expected to be conserved, but there were also important differences between all isolates. The implications of these results, and of relationships amongst these and other sequenced isolates of MSV, are discussed.
authors.affiliation: Department of Microbiology, University of Cape Town, Republic of South Africa.
authors.forename: B A
authors.initials: BA
authors.lastname: Clarke
authors.forename: E P
authors.initials: EP
authors.lastname: Rybicki
authors.forename: F L
authors.initials: FL
authors.lastname: Hughes
authors.forename: R
authors.initials: R
authors.lastname: Kirby
authors.forename: M B
authors.initials: MB
authors.lastname: von Wechmar
mesh_terms: D000353:Africa, Southern; D015153:Blotting, Western; D002213:Capsid / Q000032:analysis; D003001:Cloning, Molecular; D004279:DNA, Viral / Q000235:genetics*; D004797:Enzyme-Linked Immunosorbent Assay; D010935:Plant Diseases; D010942:Plant Viruses / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D012150:Polymorphism, Restriction Fragment Length; D015183:Restriction Mapping; D003313:Zea mays / Q000382:microbiology
chemical_list: D004279:DNA, Viral