title: Sequence diversity and virulence in Zea mays of Maize streak virus isolates.
abstract: Full genomic sequences were determined for 12 Maize streak virus (MSV) isolates obtained from Zea mays and wild grass species. These and 10 other publicly available full-length sequences were used to classify a total of 66 additional MSV isolates that had been characterized by PCR-restriction fragment length polymorphism and/or partial nucleotide sequence analysis. A description is given of the host and geographical distribution of the MSV strain and subtype groupings identified. The relationship between the genotypes of 21 fully sequenced virus isolates and their virulence in differentially MSV-resistant Z. mays genotypes was examined. Within the only MSV strain grouping that produced severe symptoms in maize, highly virulent and widely distributed genotypes were identified that are likely to pose the most serious threat to maize production in Africa. Evidence is presented that certain of the isolates investigated may be the products of either intra- or interspecific recombination.
authors.affiliation: Department of Moleculare Cell Biology, University of Cape Town, Cape Town, South Africa, 7701.
authors.forename: D P
authors.initials: DP
authors.lastname: Martin
authors.forename: J A
authors.initials: JA
authors.lastname: Willment
authors.forename: R
authors.initials: R
authors.lastname: Billharz
authors.forename: R
authors.initials: R
authors.lastname: Velders
authors.forename: B
authors.initials: B
authors.lastname: Odhiambo
authors.forename: J
authors.initials: J
authors.lastname: Njuguna
authors.forename: D
authors.initials: D
authors.lastname: James
authors.forename: E P
authors.initials: EP
authors.lastname: Rybicki
mesh_terms: D017791:Geminiviridae / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D014644:Genetic Variation; D016679:Genome, Viral; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA; D014774:Virulence; D003313:Zea mays / Q000821:virology*