Alternaria is a very common fungal genus, including numerous saprophytic, endophytic, and pathogenic species widely distributed in soil and decaying organic matter. It includes pathogenic species that can invade vegetable crops before and after harvesting and is responsible for considerable economic losses, due to the fact that it reduces the yield of the crops and produces alterations in the vegetables during their storage. Species of the genus Alternaria synthesize more than 70 secondary metabolites toxic to plants (phytotoxins), some of which also affect people and animals, which is why they are considered mycotoxins.