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The aim of this study was to evaluate the potential use of an e-nose in combination with lateral flow immunoassays for rapid aflatoxin and fumonisin occurrence/co-occurrence detection in maize samples. For this purpose, 161 samples of corn have been used. Below the regulatory limits, single-contaminated, and co-contaminated samples were classified according to the detection ranges established for commercial lateral flow immunoassays (LFIAs) for mycotoxin determination. Correspondence between methods was evaluated by discriminant function analysis (DFA) procedures using IBM SPSS Statistics 22. Stepwise variable selection was done to select the e-nose sensors for classifying samples by DFA. The overall leave-out-one cross-validated percentage of samples correctly classified by the eight-variate DFA model for aflatoxin was 81%. The overall leave-out-one cross-validated percentage of samples correctly classified by the seven-variate DFA model for fumonisin was 85%. The overall leave-out-one cross-validated percentage of samples correctly classified by the nine-variate DFA model for the three classes of contamination (below the regulatory limits, single-contaminated, co-contaminated) was 65%. Therefore, even though an exhaustive evaluation will require a larger dataset to perform a validation procedure, an electronic nose (e-nose) seems to be a promising rapid/screening method to detect contamination by aflatoxin, fumonisin, or both in maize kernel stocks.

The ascomycete Neurospora crassa is classical model organisms in biology. So far, a phylogenetic analysis based on genomic sequences of four non-functional nuclear loci has been reported for 44 natural isolates of N. crassa. Three subgroups (clades) with a distinct geographical distribution have been identified: clade A (Caribbean Basin and Ivory Coast), clade B (Europe, Ivory Coast and India), and clade C (India). Here, we report the results of a phylogenetic analysis of 16 additional isolates. Six of these were from the Caribbean Basin, eight from Europe and one from Pakistan and one from Thailand. The previously described clades and their geographical distribution were generally confirmed. All Caribbean isolates belonged to clade A and all European isolates belonged to clade B, with the exception of one isolate from Italy, which also belonged to clade A, suggesting a transport from the Caribbean Basin or the Ivory Coast to Europe. Interestingly, the isolates from Pakistan and Thailand were found in a separate group, basal to all other clades. Their phylogenetic classification is not yet clear as they might belong to N. crassa but as well to N. perkinsii, potentially representing yet undescribed phylogenetic groups or species of Neurospora, or hybrids.