Species Diversity of and Toxin Production by Gibberella fujikuroi Species Complex Strains Isolated from Native Prairie Grasses in Kansas

Abstract

Fusarium species from agricultural crops have been well studied with respect to toxin production and genetic diversity, while similar studies of communities from nonagricultural plants are much more limited. We examined 72 Fusarium isolates from a native North American tallgrass prairie and found that Gibberella intermedia (Fusarium proliferatum), Gibberella moniliformis (Fusarium verticillioides), and Gibberella konza (Fusarium konzum) dominated. Gibberella thapsina (Fusarium thapsinum) and Gibberella subglutinans (Fusarium subglutinans) also were recovered, as were seven isolates that could not be assigned to any previously described species on the basis of either morphological or molecular characters. In general, isolates from the prairie grasses produced the same toxins in quantities similar to those produced by isolates of the same species recovered from agricultural hosts. The G. konza isolates produce little or no fumonisins (up to 120 g/g by one strain), and variable but generally low to moderate amounts of beauvericin (4 to 320 g/g) and fusaproliferin (50 to 540 g/g). Toxicity to Artemia salina larvae within most species was correlated with the concentration of either beauvericin or fusaproliferin produced. Organic isolates from some cultures of G. moniliformis were highly toxic towards A. salina even though they produced little, if any, beauvericin or fusaproliferin. Thus, additional potentially toxigenic compounds may be synthesized by G. moniliformis strains isolated from prairie grasses. The Fusarium community from these grasses appears to contain some species not found in surrounding agricultural communities, including some that probably are undescribed, and could be capable of serving as a reservoir for strains of potential agricultural importance.

Complete genetic linkage maps from an interspecific cross between Fusarium circinatum and Fusarium subglutinans

“…Fusarium fujikuroi (mating population C) and Fusarium proliferatum (mating population D) are defined as being different biological species, yet a few isolates have been shown to be sexually compatible ( [Desjardins et al, 1997] and [Leslie et al, 2004b]), indicating the limitations of the biological species concept in the Liseola section of Fusarium. A naturally occurring hybrid has also been identified (Leslie et al, 2004a). One hypothesis to explain the presence of a naturally occurring hybrid is that of a hybrid swarm, possibly being geographically separated or occurring on a specific host.…”

Biochemical and Molecular Analyses of Gibberellin Biosynthesis in Fungi

“…Diversity of GA Production and Biosynthetic Genes in Fungi G. fujikuroi (Sawada) Ito in the Ito & K. Kimura species complex, which includes species from Fusarium sections Liseola and Elegans, is composed of at least nine reproductively isolated biological species (mating populations) denoted by letters A (MP-A) through to I [40][41][42] These species produce mycotoxins and secondary metabolites, including moniliformin, fumonisins, fusaric acid and beauvericin.…”

Population Structure of the Gibberella fujikuroi Species Complex Associated with Rice and Corn in Korea

“…The G. fujikuroi species complex, a monophyletic lineage, consists of at least nine biological species, formerly designated as mating populations (MPs) (Britz et al, 1999;Leslie 1999;Leslie et al, 2004), and numerous additional Fusarium anamorphs that are assigned to phylogenetically distinct species O'Donnell et al, 1998;O'Donnell et al, 2000).…”