Fusarium graminearum SPECIES COMPLEX: IMPACT OF NUTRITIONAL CONDITIONS CULTURE MEDIA ON ITS GROWTH

BELIZAN, M.M.E.; VATTUONE, M.A.; CATALAN, C. A. N,; SAMPIETRO, D.A.

Tucuman

Congreso; THIRD JOINT MEETING OF THE BIOLOGY SOCIETIES OF ARGENTINA; 2015

Sociedades Argentinas de Biologia

Fusarium graminearum morphological species generate ear rot of corn, reducing grain yield and contaminating it with toxic trichothecenes for humans and animals. At present these species are considered as a complex of phylogenetic species, the phenotypic significance of this genetic diversity being unknown. The objective of this study was to assess the growth rate of phylogenetic species of the Fg complex in culture media prepared from natural substrates and YES medium recommended for growing Fusarium. The effect of the media was studied using YES medium, extract of whole corn and ground corn 3% with and without glucose supplementation on Fusarium graminearum sensu estricto (Fgss), Fusarium boothii (Fb) and Fusarium meridionale (Fm) 25°C by testing microdilution. Assessment of growth was made every day for 20 days through microplate reader by reading absorbance at 630 nm. Growth rates were observed until day 7 in all species. Growth was higher in YES medium followed by extract of ground corn andthen by extract of whole corn. In the YES medium, growth rate was higher for Fgss than for other species. The addition of glucose to corn extracts did not cause variations in the response. While a higher growth rate was observed in the YES medium, in the ground corn extract it showed a reproducible response. The advantage of the ground corn extract is that it allowed the detection ofreproducible growth rates, easily measurable, in not very long periods and within the dynamic range of detection of theabsorbance reader.