Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 3/22/1999
Publication Date: N/A
Interpretive Summary: Despite considerable progress in understanding the systematics of plant pathogenic fungi, the identification and classification of some groups of fungi is still difficult. This is particularly true for members of the complex genus Fusarium. Recent molecular work has shown that most species in the asexually reproducing genus Fusarium that cause serious disease of plants have sexual states in Gibberella. In this paper the characteristic of species of Fusarium having Gibberella sexual states are enumerated and both genera are described and illustrated. A key is presented for the identification of the species of Gibberella and their Fusarium states. This work will be useful to plant pathologists and extension agents who seek to identify, characterize, and control these fungi causing diseases of plants.
Technical Abstract: Although the genus Fusarium is restricted to the Hypocreales, it is polyphyletic because species of the anamorph genus are anamorphs of different teleomorph genera of that order. Because the type species of Fusarium, F. sambucinum Fuckel, is the anamorph of Gibberella pulicaris (Fr.) Sacc., Fusarium s. str. is the anamorphic or mitotic state of Gibberella. DNA sequence analyses have shown that asexual species such as F. oxysporum are actually asexual Gibberella species. Although there is a vast literature about the biology and genetics of Gibberella, mainly under the name of Fusarium, little effort has been expended on characterizing the perithecia, asci or ascospores of the species of this genus. In this paper, we discuss how to recognize a Gibberella perithecium and the background to the taxonomy of the genus. We also discuss recent research in the definition of biological and `phylogentic' species within Gibberella. Finally, we present a key to the Gibberella species that are proven to have Fusarium anamorphs.