Forecasting models for mycotoxins in cereal grains during cultivation are useful for pre-harvest and post-harvest mycotoxin management. Some of such models for deoxynivalenol (DON) in wheat, using two different modelling techniques, have been published. This study aimed to compare and cross-validate three different modelling approaches for predicting DON in winter wheat using data from the Netherlands as a case study. To this end, a published empirical model was updated with a new mixed effect logistic regression method. A mechanistic model for wheat in Italy was adapted to the Dutch situation. A new Bayesian network model was developed to predict DON in wheat. In developing the three models, the same dataset was used, including agronomic and weather data, as well as DON concentrations of individual samples in the Netherlands over the years 2001–2013 (625 records). Similar data from 2015 and 2016 (86 records) were used for external independent validation. The results showed that all three modelling approaches provided good accuracy in predicting DON in wheat in the Netherlands. The empirical model showed the highest accuracy (88%). However, this model is highly location and data-dependent, and can only be run if all of the input data are available. The mechanistic model provided 80% accuracy. This model is easier to implement in new areas given similar mycotoxin-producing fungal populations. The Bayesian network model provided 86% accuracy. Compared with the other two models, this model is easier to implement when input data are incomplete. In future research, the three modelling approaches could be integrated to even better support decision-making in mycotoxin management.

Fusarium graminearum is the predominant component of the Fusarium head blight complex of wheat. F. graminearum ascospores, which initiate head infection, mature in perithecia on crop residues and become airborne. The effects of temperature (T) and moisture on perithecium production and maturation and on ascospore production on maize stalk residues were determined. In the laboratory, perithecia were produced at temperatures between 5 and 30°C (the optimum was 21.7°C) but matured only at 20 and 25°C. Perithecia were produced when relative humidity (RH) was >75% but matured only when RH was >85%; perithecium production and maturation increased with RH. Equations describing perithecium production and maturation over time as a function of T and RH (R 2 > 0.96) were developed. Maize stalks were also placed outdoors on three substrates: a grass lawn exposed to rain; a constantly wet, spongelike foam exposed to rain; and a grass lawn protected from rain. No perithecia were produced on stalks protected from rain. Perithecium production and maturation were significantly higher on the constantly wet foam than on the intermittently wet lawn (both exposed to rain). Ascospore numbers but not their dispersal patterns were also affected by the substrate. Fusarium head blight (FHB) is one of the most widespread and dangerous diseases of wheat and other small-grain cereals (1, 2). Up to 17 species belonging to the genera Fusarium and Microdochium have been recognized as responsible for FHB (3). Fusarium graminearum has been considered the predominant species in most cereal-growing areas of the world (4, 5, 6). Symptoms of the disease include premature bleaching of spikes or spikelets, sterile florets, poorly filled grains, and grains that are shriveled and discolored (white to pale pink) (7). The disease reduces yield, grain quality, including contamination by mycotoxins, and seed quality (3).Wheat spikes are receptive to infection from flowering to the soft-dough stage (8). Ascospores and macroconidia are the main inocula (3,7,9) and are typically produced on the residues of the previous crop (4, 7). The fungus can survive as a saprophyte on the previous crop's residue for 2 or more years (10,11,12). Although both ascospores and conidia can be detected in cereal crops, ascospores are more prevalent than conidia in many areas (3,4,7,13). Macroconidia are produced in sporodochia and are dispersed for short distances by splashing rain (14,15,16). Ascospores mature in perithecia and are forcibly discharged into the air; they are then airborne and can travel meters to kilometers (9,17,18,19).The main factors influencing production of perithecia and ascospores are light, temperature, and moisture. Light with wavelengths between 300 and 320 nm is essential for the induction of perithecium (20). Paulitz (21) observed more perithecia on the side of debris exposed to direct light; perithecia were also found on grains buried at 5 to 10 cm, but they did not produce ascospores (10).Perithecia and ascospores are formed under warm and moist co...

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