OCCURRENCE OF FUMONISIN B-1 IN MAIZE GROWN IN COSTA-RICA

Fusarium moniliforme is one of the most frequent fungal pathogens foun d in corn. Samples of corn grown in three different regions of Costa R ica were collected and analyzed for the presence of fumonisins, metabo lites produced by F. moniliforme. Results indicate that fumonisin B-1 was present in 89% of the samples. Maize grown in Costa Rica is theref ore contaminated with fumonisin B-1, and contamination depends on geog raphical region and period of collection. Microbiological analysis rev ealed the presence of F. moniliforme-type isolates in 86% of the maize samples. Average levels of fumonisin B-1 per region-Brunca, Huetar No rte, and Huetar Atlantica-were 2.50, 3.58, and 1.81 ppm, respectively. Mean fumonisin B-1 values were 2.13 ppm with a minimum of 0.00 ppm an d a maximum of 6.32 ppm. Maize from the Huetar Atlantica region showed significantly (a = 0.05) higher levels off. moniliforme-type isolates than maize from the Brunca and Huetar Norte regions.