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Global food safety depends on continuous monitoring of food contaminants such as mycotoxins in cereals and cereal-derived products. Here, we combine this type of investigation with quantitative occurrence data on Fusarium infestation of these products in extensive correlation studies. Finally, this contributes to a thorough understanding of the presence, origin and physiology of Fusarium Head Blight (FHB) related mycotoxins and the correlations within their ranks. Two hundred and thirty-seven samples were analyzed from diverse cereal matrices, representing the most important stages of the cereal food and feed chain in Belgium. Food, feed and non-processed field samples were investigated, with a strong emphasis on whole-grain food products. Two approaches were pursued to estimate the full scope of FHB and its repercussions: UPLC-MS/MS was applied to detect twelve different mycotoxins, and Q-PCR was used to measure the presence of ten Fusarium species. We found that different matrices have different characteristic contamination profiles, and extensive correlation studies identified certain mycotoxins for future assessment (e.g. moniliformin produced by the Fusarium avenaceum/Fusarium tricinctum species group). The investigated harvest year of 2012 yielded many non-processed field materials containing elevated levels of deoxynivalenol (DON), while even in a so-called DON-year less prevalent toxins such as T-2 and HT-2 might be considered problematic due to their consistent co-occurrence with related mycotoxins. Our data illustrate complex interactions between the many Fusarium species that are responsible for FHB and their mycotoxins. Correlation studies demonstrate that consistent co-occurrence of mycotoxins is not to be neglected, and pinpoint issues for future surveillance and legislation., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Powdery mildew is an important disease of cereals, affecting both grain yield and end-use quality. The causal agent of powdery mildew on cereals, Blumeria graminis, has been classified into eight formae speciales (ff.spp.), infecting crops and wild grasses. Advances in research on host specificity and resistance, and on pathogen phylogeny and origins, have brought aspects of the subspecific classification system of B. graminis into ff.spp. into question, because it is based on adaptation to certain hosts rather than strict host specialization. Cereals therefore cannot be considered as typical non-hosts to non-adapted ff.spp. We introduce the term 'non-adapted resistance' of cereals to inappropriate ff.spp. of B. graminis, which involves both pathogen-associated molecular pattern-triggered immunity (PTI) and effector-triggered immunity (ETI). There is no clear distinction between the mechanisms of resistance to adapted and non-adapted ff.spp. Molecular evolutionary data suggest that the taxonomic grouping of B. graminis into different ff.spp. is not consistent with the phylogeny of the fungus. Imprecise estimates of mutation rates and the lack of genetic variation in introduced populations may explain the uncertainty with regard to divergence times, in the Miocene or Holocene epochs, of ff.spp. of B. graminis which infect cereal crop species. We propose that most evidence favours divergence in the Holocene, during the course of early agriculture. We also propose that the forma specialis concept should be retained for B. graminis pathogenic on cultivated cereals to include clades of the fungus which are strongly specialized to these hosts, i.e. ff.spp. hordei, secalis and tritici, as well as avenae from cultivated A. sativa, and that the forma specialis concept should no longer be applied to B. graminis from most wild grasses., (© 2013 BSPP AND JOHN WILEY & SONS LTD.)

Wheat production in African countries is a major challenge for their development, considering their increasing consumption of wheat flour products. In the Democratic Republic of Congo, wheat and wheat-based products are the important imported food products although there is a potential for the cultivation of small grain cereals such as durum wheat, wheat and triticale. Trials done in Lubumbashi in the Katanga Province have shown that Septoria Leaf Blotch, Septoria Glume Blotch and Fusarium head blight are the main constraints to the efficient development of these cultures. Some varieties of Elite Spring Wheat, High Rainfall Wheat, Triticale and Durum Wheat from CIMMYT were followed during 4 growing seasons and agronomic characteristics and their levels of disease resistance were recorded. Correlations of agronomic characteristics with yields showed that in most cases, thousand kernel weight is the parameter that has the most influence on the yield level (p < 0.0001). The analysis of variance for all diseases showed that there were significant effects related to the year, the species and the interaction years x species. Triticale varieties seem to have a better resistance against the two forms of Septoria compared to wheat varieties but, they seem to be more sensitive to Fusarium Head Blight than wheat varieties. However, the Fusarium Head Blight has a rather low incidence in Lubumbashi.

The development of new crop species and their associated agro-ecosystems led simultaneously to the emergence of new pathogens (Stukenbrock and McDonald, 2008). This research focused on the recent emergence of powdery mildew (Blumeria graminis) on triticale (x Triticosecale Wittmack). In a first part, we aimed to gain insights into the evolutionary origin of this pathogen on its new host. A secondary aim was to investigate the presence of powdery mildew resistance in current commercial triticale cultivars, including its cellular basis of resistance. To address these research goals, we have pursued a molecular, pathological and cytological approach. This discussion will reflect on the experimental findings described in this research and their impact for future management of powdery mildew on triticale and other cereals.

In the present study, a quantitative dietary exposure assessment of mycotoxins and their masked forms was conducted on a national representative sample of the Belgian population using the contamination data of cereal-based foods. Cereal-based food products (n=174) were analysed for the occurrence of deoxynivalenol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, zearalenone, α-zearalenol, β-zearalenol, T-2-toxin, HT-2-toxin, and their respective masked forms, including, deoxynivalenol-3-glucoside, zearalenone-4-glucoside, α-zearalenol-4-glucoside, β-zearalenol-4-glucoside and zearalenone-4-sulfate. Fibre-enriched bread, bran-enriched bread, breakfast cereals, popcorn and oatmeal were collected in Belgian supermarkets according to a structured sampling plan and analysed during the period from April 2010 to October 2011. The habitual intake of these food groups was estimated from a national representative food intake survey. According to a probabilistic exposure analysis, the mean (and P95) mycotoxin intake for the sum of the deoxynivalenol-equivalents, zearalenone-equivalents, and the sum of HT-2-and T-2-toxin for all cereal-based foods was 0.1162 (0.4047, P95), 0.0447 (0.1568, P95) and 0.0258 (0.0924, P95) μg kg(-1)body weight day(-1), respectively. These values were below the tolerable daily intake (TDI) levels for deoxynivalenol, zearalenone and the sum of T-2 and HT-2 toxin (1.0, 0.25 and 0.1 μg kg(-1)body weight day(-1), respectively). The absolute level exceeding the TDI for all cereal-based foods was calculated, and recorded 0.85%, 2.75% and 4.11% of the Belgian population, respectively., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

An LC-MS/MS method was developed and validated for the simultaneous determination of deoxynivalenol, zearalenone, T-2-toxin, HT-2-toxin and metabolites, including 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, deoxynivalenol-3-glucoside, α-zearalenol, β-zearalenol, zearalenone-4-glucoside, α-zearalenol-4-glucoside, β-zearalenol-4-glucoside and zearalenone-4-sulfate in maize, wheat, oats, cornflakes and bread. Extraction was performed with acetonitrile/water/acetic acid (79/20/1, v/v/v) followed by a hexane defatting step. After filtration, the extract was evaporated and the residue was redissolved in mobile phase for injection. The mobile phase, which consisted of a mixture of methanol and water with 10 mM ammonium acetate, was adjusted to pH 3 with glacial acetic acid. A sample clean-up procedure was not included because of the low recoveries of free and masked mycotoxins and their differences in polarity. The method allowed the simultaneous determination of 13 Fusarium mycotoxins in a one-step chromatographic run using a Waters Acquity UPLC system coupled to a Quattro Premier XE mass spectrometer. The method was validated for several parameters such as linearity, apparent recovery, limit of detection, limit of quantification, precision, expanded measurement uncertainty and specificity. The limits of detection varied from 5 to 13 ng g⁻¹; those for the limit of quantification from 10 to 26 ng g⁻¹. The results of the performance characteristics of the developed LC-MS/MS method were in good agreement with the criteria mentioned in Commission Regulation (EC) No. 401/2006. Thirty samples of a variety of food and feed matrices were sampled and analysed between July 2010 and January 2011.

Tank-mix adjuvants can increase the overall performance of plant protection products. Their most important ways of action are the improved retention, spreading, wetting, and penetration of the pesticide on the target and the reduction of fine droplets. In this paper, deposition and spreading of the systemic fungicide propiconazole on triticale ears were quantified. A better deposition and spreading of fungicide on the ear may be a possible help for the Fusarium problem in triticale, wheat, and other cereals. Triticale ears were applied with propiconazole in combination with 11 different tank-mix adjuvants. Vegetable oil, alcohol ethoxylates, lactate ester, trisiloxanes, and an amphoteric molecule were included in this experiment. When no tank-mix adjuvant was used, the lower part of the ear was reached five times less by the propiconazole spray than the upper part of the ear. When the tank-mix adjuvant was combined with the propiconazole formulation, an increase in residue on both the upper and the lower part of the ear was observed. A higher residue on the upper half of the ear means a better deposition, while a higher residue on the lower part of the ear is related to a better downward spreading over the grains and the needles of the ear. The combination of those two observations makes it interesting to use tank-mix adjuvants for the prevention of mycotoxin-producing Fusarium species. The advantages are emphasized even more when cost effectiveness was calculated. The use of a proper tank-mix adjuvant can result in 40% lower cost per application per hectare.

The food production in Katanga is inadequate and causes food insecurity for more than 400.000 people. Nowadays the Katanga province relies for more than 75 % on imported wheat and wheat flour from neighbouring countries. The absence of adapted germplasm is one of the mean reasons for the low production levels of small grains and as consequence the disinteresting of farmers for producing wheat. To select well adapted genotypes a screening test with wheat (T. aestivum) and triticale (x Triticosecale Wittm.) was establish during the rainy season of 2006-2007 at the farm Kasapa (25 km outside Lubumbashi). Glume blotch (S. nodorum teleomorph: Leptosphaeria nodorum) was the most dominant disease during the rainy season 2006 - 2007. Glume blotch could be detected on leaves and ears of wheat as well as of triticale. Fusarium head blight (Fusarium sp. teleomorph: Gibberella sp.) was also present but to a less extend. Rust or mildew fungus were not recorded on any genotype. The disease pressure made it possible to screen more disease tolerant genotypes of wheat and triticale. The differences were most clear for ear glume blotch but especially on triticale differences between FHB tolerant and susceptible genotypes could be made. For triticale and wheat respectively 25 and 32 % of the genotypes were put in the breeding pole to select new varieties.