Two-dimensional environmental profiles of growth, deoxynivalenol and nivalenol production by Fusarium culmorum on a wheat-based substrate

Abstract

Aims: To determine the effect of interacting conditions of water activity (aw, 0.99-0.85), temperature (15, 25°C) and time (40 days) on growth and production of the mycotoxins deoxynivalenol (DON) and nivalenol (NIV) by Fusarium culmorum on a wheat-based agar medium. Methods and Results: Fusarium culmorum grew optimally at 0.995aw and minimally at 0.90 at both 15 and 25°C. No growth was observed at <0.90aw. Overall, temperature, aw and their interaction had a statistically significant effect on the growth rate of F. culmorum. Production of both DON and NIV were over a much narrower range (0.995-0.95aw) than that for growth. The highest concentrations of DON and NIV levels were produced at 0.995aw and 0.981aw at 25°C, respectively, after 40 days of incubation. Statistically, aw, temperature and incubation time, and aw x temperature and temperature x incubation time had a statistically significant effect on DON/NIV production. Conclusions: This is the first detailed report on the two-dimensional environmental profiles for DON/NIV production by F. culmorum in the UK. Significance and Impact of the Study: As part of a hazard analysis critical control point (HACCP) approach, this type of information is critical in monitoring critical control points for prevention of DON/NIV entering the wheat production chain.