is one of the most relevant fungal species in maize responsible for ear, stalk and seedling rot, as well as the fumonisin contamination of kernels. Plant lipoxygenases (LOX) synthesize oxylipins that play a crucial role in the regulation of defense mechanisms against pathogens and influence the outcome of pathogenesis. To better uncover the role of these signaling molecules in maize resistance against , the functional characterization of the 9-LOX gene, , was carried out in this study by employing mutants carrying Mu insertions in this gene (named as UFMu). In this regard, the genotyping of five UFMu identified the mutant UFMu10924 as the only one having an insertion in the coding region of the gene. The impact of mutagenesis on kernel defense against and fumonisin accumulation were investigated, resulting in an increased fungal susceptibility compared to the inbred lines W22 and Tzi18. Moreover, the expression of most of the genes involved in the LOX, jasmonic acid (JA) and green leaf volatiles (GLV) pathways, as well as LOX enzymatic activity, decreased or were unaffected by fungal inoculation in the mutant UFMu10924. These results confirm the strategic role of in controlling defense against and its influence on the expression of several LOX, JA and GLV genes.