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A study was carried out to investigate fungi present on grapes grown in Italy. Aspergillus and Penicillium spp. isolates were identified and studied in vitro, and their ability to produce ochratoxin A (OA) was investigated. The survey involved nine vineyards, three located in northern Italy and six located in southern Italy. In 1999 and 2000, bunches of grapes at different growth stages were collected from all nine vineyards, and berry samples were placed in moist chambers and incubated. The resultant fungal colonies were then transferred to petri dishes containing Czapek yeast agar and incubated at 25 degrees C for 7 days; the fungal isolates were identified and then cultivated in liquid Czapek yeast medium and evaluated for their ability to produce OA. During the survey, 508 isolates were collected, with 477 belonging to Aspergillus spp. and 31 belonging to Penicillium spp. Among the aspergilli, species of the Fumigati, Circumdati, and Nigri sections were identified, with species of the Nigri section (464 isolates) largely predominating; for species of the Nigri section, 108 isolates were uniseriate, 270 were biseriate, and 86 were identified as Aspergillus carbonarius. Black aspergilli isolated over the 2 years of the study showed a very similar pattern. On average, the biseriates represented about 60% of the isolates collected in both years and were followed by uniseriates (21%) and A. carbonarius (19%). The most toxigenic strains proved to be those of A. carbonarius; about 60% of these isolates were OA producers and produced the highest levels of OA. A. carbonarius was more frequent in the south, but in both areas the percentages of OA-producing isolates remained the same.

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Aflatoxin (AF) contamination in maize is of worldwide importance. Aspergillus flavus and A. parasiticus are the principal fungi responsible for AF production. Based on the current literature, AFs are not considered a problem in wheat and rice at harvest and no data were found on aspergilliwheat/rice interactions in the field. Data on the effects influencing the development of A. flavus and A. parasiticus on maize and maize kernel at harvest were collected; however data on A. parasiticus and AFB 2 -G 1 -G 2 were not sufficient for further use in predictive modelling. Thus, a model was developed to predict the risk of AFB 1 contamination, due to A. flavus, in maize at harvest and further adapted to wheat and rice as host crops. The Joint Research Centre of the EC provided a database with mean daily temperatures during emergence, flowering and harvesting of maize, wheat and rice. Meteorological data (temperature, relative humidity and rain) obtained from the LARS weather generator, were used as input for the modelling of crop phenology and A. flavus behaviour. The output was designed at a 50 x 50 km scale over the European territory and generated over 100 years, in three different climate scenarios (present and A2 and B2 storylines, or + 2 °C and + 5 °C scenarios, proposed by the Intergovernmental Panel on Climate Change). Predictions showed a reduction in season length and an advance in flowering and harvest dates leading to an enlargement of the crop growing areas towards north EU, mainly for maize and rice, because earlier ripening could occur in these areas. The risk of A. flavus contamination was expected to increase in maize, both in the + 2 °C and + 5 °C scenarios, to be very low in wheat and to be absent in rice. Results were discussed and recommendations were made on data collection and prevention measures on AF risks.

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