Evaluation of fumonisin-aflatoxin co-occurrence in Brazilian corn hybrids by ELISA

The natural co-occurrence of fumonisins and aflatoxins was investigated in freshly harvested corn kernels (150 samples, 62 hybrids), acquired from the Central-Southern (27 samples, 21 hybrids), Central-Western (86 samples, 51 hybrids) and Northern (37 samples, 18 hybrids) regions of the State of Par ana, Brazil using enzyme-linked immunosorbent assay (ELISA). Fumonisins wer e detected in 147 (98%) samples at a concentration range of 0.096 to 22.6 m ug/g, while aflatoxins were detected in 17 (11.3%). All the aflatoxin-posit ive samples (range 38.0-460.0 ng/g) came from the Central-Western region an d were co-contaminated with fumonisins. Fumonisin contamination was higher in corn from the Northern (9.85 mug/g) and Central-Western regions (5.08 mu g/g), when compared with the Central-Southern region (1.14 mug/g). The over all evaluation detected 62% samples with fumonisin levels less than or equa l to5.0 mug/g. Regional differences affected fumonisin levels in the same h ybrid, regardless of Fusarium count and moisture content, suggesting interf erence from climatic conditions, in addition to the local predominance of t oxigenic strains of the Fusarium biotype.