Assessing the mycotoxigenic threat of necrotrophic pathogens of wheat

Pathogenic fungi are the causal agents of many significant plant diseases around the world. These diseases often result in significant yield reductions, leading to lower food production rates and economic losses. Several of these pathogenic fungi also produce mycotoxins during infection, which are harmful to human and animal health. Whilst some of these toxins and the fungi that produce them have been studied intensively, the mycotoxigenic potential of many of these pathogens remains largely unknown. Included within these fungi are the necrotrophic pathogens of wheat, Stagonospora nodorum, Pyrenophora tritici-repentis and Alternaria alternata. Recent studies have demonstrated that each of these pathogens is capable of synthesizing an array of mycotoxic compounds during disease development, questioning their status as non-mycotoxin producers. This review summarises recent mycotoxin findings in these necrotrophic wheat pathogens by briefly discussing the mycotoxins identified, their toxicity and their synthesis. Future and emerging threats are also considered.