Fusarium verticillioides (Sacc.) Nirenberg (synonym F. moniliforme Sheldon) (teleomorph: Gibberella moniliformis) and F. proliferatum (Matsushima) Nirenberg (teleomorph: G. intermedia) are fungal pathogens of maize (Zea mays L.) that cause ear rot and contaminate grain with fumonisins, a family of mycotoxins that adversely affect animal and human health. The objective of this study was to estimate heritabilities of and genotypic and phenotypic correlations between fumonisin concentration, ear rot, and flowering time in two maize populations. In the (GE440 3 FR1064) 3 FR1064 backcross population, the genotypic and phenotypic correlations between ear rot and fumonisin concentration were 0.96 and 0.40, respectively. Heritability estimated on an entry mean basis was 0.75 for fumonisin concentration and 0.47 for ear rot resistance. In the NC300 3 B104 recombinant inbred line population, the genotypic and phenotypic correlations between ear rot and fumonisin concentration were 0.87 and 0.64, respectively. Heritability estimated on an entry mean basis was 0.86 for fumonisin concentration and 0.80 for ear rot resistance. Correlations between fumonisin concentration and silking date were not significant in either population, and correlations between ear rot resistance and silking date were small (less than 0.30) in both populations. Moderate to high heritabilities and strong genetic correlations between ear rot and fumonisin concentration suggest that selection for reduced ear rot should frequently identify lines with reduced fumonisin concentration. Ear rot can be screened visually and so is less costly and less time-consuming to evaluate than laboratory assays for fumonisin concentration.

T-2 toxin is a trichothecene mycotoxin produced when Fusarium fungi infect grains, especially oats and wheat. Ingestion of T-2 toxin contaminated grain can cause diarrhea, hemorrhaging, and feed refusal in livestock. Cereal crops infected with mycotoxin-producing fungi form toxin glycosides, sometimes called masked mycotoxins, which are a potential food safety concern because they are not detectable by standard approaches and may be converted back to the parent toxin during digestion or food processing. The work reported here addresses four aspects of T-2 toxin-glucosides: phytotoxicity, stability after ingestion, antibody detection, and the anomericity of the naturally occurring T-2 toxin-glucoside found in cereal plants. T-2 toxin-β-glucoside was chemically synthesized and compared to T-2 toxin-α-glucoside prepared with Blastobotrys muscicola cultures and the T-2 toxin-glucoside found in naturally contaminated oats and wheat. The anomeric forms were separated chromatographically and differ in both NMR and mass spectrometry. Both anomers were significantly degraded to T-2 toxin and HT-2 toxin under conditions that mimic human digestion, but with different kinetics and metabolic end products. The naturally occurring T-2 toxin-glucoside from plants was found to be identical to T-2 toxin-α-glucoside prepared with B. muscicola. An antibody test for the detection of T-2 toxin was not effective for the detection of T-2 toxin-α-glucoside. This anomer was produced in sufficient quantity to assess its animal toxicity.

The trichothecenes produced by solid and liquid cultures of Fusarium sporotrichioides were evaluated with high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). Along with the expected T-2 toxin HT-2 toxin and neosolaniol, two additional compounds were detected, which had ions 162 m/z higher than those in the mass spectra of T-2 toxin or HT-2 toxin. Fragmentation behavior of these two compounds was similar to that of T-2 toxin and HT-2 toxin. Based on LC-MS/MS behavior, it is proposed that the two compounds are T-2 toxin 3-O-glucoside and HT-2 toxin 3-O-glucoside. Production of the two glucosides was measured in kernels from wheat and oat inoculated with F. sporotrichiodes, as well as in cultures grown in liquid media and on cracked corn or rice. Production of glucosides in wheat and oats suggest that they may also be present in naturally contaminated cereals.

The problems associated with mycotoxin contamination of foods and feeds are well established and, in many cases, have been known for a long time. Consequently, the techniques for detecting known mycotoxins are quite advanced and range from methods for directly detecting the toxins themselves, based upon physical characteristics of the toxins, to methods for indirectly detecting the toxins, such as immunoassays. This review focuses on recent technologies that can be used to detect mycotoxins and, as such, is not a comprehensive review of the mycotoxin analytical literature. Rather, the intent is to survey the range of technologies from those that are instrument intensive such as modern chromatographic methods to those that require no instrumentation, such as certain immunoassays and biosensors. In particular, mass spectrometric techniques using ambient ionization offer the intriguing possibility of non-destructive sampling and detection. The potential application of one such technique, desorption electrospray ionization (DESI), is demonstrated for fumonisin B(1) on maize. While methods for detecting mycotoxins are quite advanced, the need remains for assays with increased throughput, for the exploration of novel detection technologies, and for the comprehensive validation of such technologies as they continue to be developed.