Fusarium species (Gibberella fujikuroi complex) isolated from maize hybrids harvested in Mexico

REYES VELAZQUEZ, W.P; FIGUEROA GOMEZ, R.M.; REYNOSO M.M.; TORRES, A.M; CHULZE, S,N,

Villa Carlos Paz

Otro; Advances in research on toxigenic fungi and mycotoxins in Soth America ensuring food and feed safety in a myco-globe context; 2006

Myco-Globe- Sixth Framework Programme

Maize (Zea mays L.) is one of the main crops for the Mexican  economy and consumed as "tortillas", "tostadas" and other maize based foods. Fusarium species (Gibberella fujikuroi complex) is able to cause root rot, stalk rot and kernel or ear rot, and produce several mycotoxins such as fumonisins, beauvericin, and fusaproliferin. The aims of this study was: -to evaluated Fusarium population isolated from maize harvested in Jalisco State, Mexico. Three Fusarium species were isolated, Fusarium verticillioides (G. moniliformis, Gibberella fujikuroi mating population A), F. proliferatum (G. intermedia, G. fujikuroi mating population D) and F. subglutinans (G. subglutinans, G. fujikuroi mating population E). Both mating types MAT-1/MAT-2 were detected. The alleles frequency was dependent on the mating population evaluated. We determined the effective population number for mating population A (Ne) due to it was the only population from which recovered a good number of strains. The Ne for mating type [Ne(mt)] was 20% of the count (total population) and the Ne for hermaphrodite status [Ne(f)] was 91%. The mating population A will be able to recombine by sexual reproduction so that will have more adaptive advantages to the selection pressures. Fumonisin production was dependant on the mating population to which the strain belong. Although, all maize samples were contaminated with fumonisins. The toxin levels found were not higher than 4 µg g-1.