**3. Overview of mycotoxin-contaminating cereals**

Mycotoxin contamination can occur pre-harvest when the crop plant is growing or postharvest during processing. Storage of cereals at temperatures over 37°C increases humidity during prolonged storage times is a factor for crops and cereals to be susceptible to mold growth and mycotoxin contamination [16]. The susceptibility of the grain is another factor to consider, presenting greater susceptibility maize and lower rice. Animal pests, weeds and pathogens impact yield and quality of cereals. *F. graminearum* mostly affects cereals, including maize, wheat and barley. The predominant *Fusarium* species associated with ear and stalk rots are *F. graminearum* followed by *F. verticillioides*, *F. proliferatum* and *F. culmorum* [21]. These *Fusarium* species are also capable of producing mycotoxins, which contribute to pre-harvest contamination of human food and animal feed impacting health [7]. Among *Fusarium* spp., *F. graminearum* is the most common agent causing *Fusarium* head blight [26]. The major mycotoxin type of *F. graminearum*, *F. sporotrichioides* and *Fusarium avenaceum* is the trichothecene type-B mycotoxin class of fungi capable of producing deoxynivalenol and its derivatives (3Ac-deoxynivalenol, 15Ac-deoxynivalenol) or nivalenol. The nivalenol-producing isolates of *F. graminearum* have been found to be more aggressive in maize than the deoxynivalenolproducing isolates [15]. On the other hand, maize production is mainly affected by diseases caused by the species *Fusarium proliferatum*, *F. verticillioides* and *F. subglutinans* and mycotoxin generators including fusaric acid, fusarins and fumonisins. Among fumonisins, fumonisin B1 (FB1), FB2 and FB3 are most frequently encountered in maize kernels [1, 27]. *Fusarium sporotrichioides* is a common soil-borne plant pathogen causing dry rot of potato [28].
