Modelling, predicting and mapping the emergence of aflatoxins in cereals in the EU due to climate change
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 AFB2-G1-G2 were not sufficient for further use in predictive modelling. Thus, a model was developed to predict the risk of AFB1 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.