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Abstract: Natural mycoflora and co-occurrence of fumonisins and aflatoxins were evaluated in 300 freshly-harvested corn samples (2003 and 2004 crops) collected at two points of the production chain in the Northern region of Paraná State, Brazil. In the 2003 crop, fumonisins were detected in 100% of samples and the mean levels were 2.54μg/g in the reception and 3.12μg/g in the pre-drying samples. On the other hand, in the 2004 crop fumonisins were detected in 98.9% and 95% of the reception and pre-drying samples, respectively. The mean levels were 1.31μg/g in the reception, and 1.36μg/g in the pre-drying samples. Aflatoxins were not detected in 92% of the samples analysed. The maximum probable daily intake (PDIM) estimated for the Brazilian population (0.95μg/kg body weight/day) is below the tolerable daily intake of 2.0μg/kg body weight/day for fumonisin B1. [Copyright &y& Elsevier]

Grain yield data were used from 65 maize cultivar trials carried out in the State of the Rio Grande do Sul, Brazil, in the years of 2002/2003, 2003/2004 and 2004/2005, with the objective of comparing the following methods of adaptability and stability analysis: Yates and Cochran, Plaisted and Peterson, Wricke, Annicchiarico, Finlay and Wilkinson, Eberhart and Russell, Tai, Toler, Silva and Barreto, Cruz et al., Huehn, Lin and Binns modified by Carneiro and analysis AMMI. To verify the degree of association between the estimates of adaptability and stability parameters, obtained by the different methods, the Spearman correlation coefficient was used. There is an agreement in the indication of maize cultivars by the methods of Plaisted and Peterson and Wricke, of Annicchiarico and Lin and Binns modified by Carneiro, of Eberhart and Russell and Tai, and of Toler and Silva and Barreto, which counter-indicates their concomitant use. To a lesser degree of association the AMMI analysis agrees with the estimates of the stability parameters, Plaisted and Peterson, Wricke, Eberhart and Russell, Tai, Silva and Barreto and Cruz et al. [ABSTRACT FROM AUTHOR]

The performance of a monoclonal antibody (MAb)-based indirect competitive ELISA (ICELISA) for fumonisin detection in corn was evaluated using 150 post-harvest corn samples from the April 1995 and March-April 1996 crop, in the State of Parana, Brazil. Compared to high performance liquid chromatography (HPLC), the correlation coefficient (r) of the results from the two methods was 0.94. The IC-ELISA detected total fumonisin levels of 1.1 to 1.5-fold higher than HPLC in 85 samples (56.6%). The concentration range of 1.0 to 5.0 mug g[sup -1] was observed in 26% of samples analysed by ELISA and in 29% by HPLC. In addition, four samples (2.7%) showed an ELISA/HPLC ratio of 0.7 to 0.99 and seven samples (4.7%) a 1.0 ratio. In 29 (13.3%) samples, IC-ELISA detected 1.6 to 2.0-fold higher values than HPLC. These data showed high correlation (r = 0.91) of IC-ELISA and HPLC for fumonisin concentration in corn contaminated with 10 mu g g[sup -1], with a detection limit of 93 ng g[sup -1]. Matrix interference was minimized by diluting the sample before the ELISA assay. MAb-based IC-ELISA may be effectively applied for fumonisin screening in corn, with advantages of simplicity, ease of sample preparation and sensitivity. [ABSTRACT FROM AUTHOR]