title: Species of Cercospora associated with grey leaf spot of maize.
abstract: Grey leaf spot is a serious yield-reducing disease of maize (Zea mays) in many parts of the world where this crop is cultivated. The causal organism associated with the disease is Cercospora zeae-maydis. Two potential sibling species have been recognized as Groups I and II. The DNA sequences for the internal transcribed spacers (ITS1 & ITS2), the 5.8S rRNA gene, elongation factor 1-alpha, histone H3, actin and calmodulin gene regions suggest that Groups I and II are two distinct species. Furthermore, Cercospora zeae-maydis (Group I) can be distinguished from C. zeina sp. nov. (Group II) by its faster growth rate on artificial media, the ability to produce cercosporin, longer conidiophores, and broadly fusiform conidia. A PCR-based test that distinguishes the two species was developed using species-specific primers designed from the histone H3 gene.
authors.affiliation: Centraalbureau voor Schimmelcultures, Fungal Biodiversity Centre, P.O. Box 85167, 3508 AD, Utrecht, The Netherlands.
authors.forename: Pedro W
authors.initials: PW
authors.lastname: Crous
authors.forename: Johannes Z
authors.initials: JZ
authors.lastname: Groenewald
authors.forename: Marizeth
authors.initials: M
authors.lastname: Groenewald
authors.forename: Pat
authors.initials: P
authors.lastname: Caldwell
authors.forename: Uwe
authors.initials: U
authors.lastname: Braun
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Harrington