Technical Abstract: The fungus Fusarium verticillioides is a pathogen of many plants and is known to produce fumonisins. These toxins have been shown to contribute to the development of maize seedling disease. Fumonisin disruption of sphingolipid biosynthesis has been demonstrated to occur during such pathogenesis. A liquid chromatographic/mass spectrometric method was developed for the analysis of fumonisin content in maize leaf tissue, as well as the elevation of biomarkers of sphingoid base disruption in those tissues. This method involved a quick extraction and subsequent analysis on a mass spectrometer. To test the efficacy of the method, seed of susceptible and resistant maize lines were inoculated with a pathogenic, fumonisin-producing strain of F. verticillioides. The maize seedlings were then harvested, and analyzed for fumonisin, as well as sphingoid bases and their 1-phosphates. Fumonisin accumulation was evident in the leaves of inoculated plants and was significantly greater in the leaves of the susceptible maize variety than the resistant variety, as was elevation of sphingoid bases and sphingoid base 1-phosphates. Unexpectedly, FB1 was preferentially accumulated in the leaf tissues over FB2 and FB3. The method developed was effective, fast, and sensitive for use in determining these indicators of disease induced by infection and toxin production.