Systemic response to Fusarium graminearum and culmorum inoculations: changes in detoxification of flag leaves in wheat

Fusarium graminearum and F. culmorum cause the most widespread wheat disease Fusarium head blight (FHB). The present study describes that the Fusarium inoculation of the wheat spikes caused systemic changes in the key elements of the antioxidant/detoxification defence system in the flag leaf during the grain filling period in wheat lines differing in biotic stress susceptibility to explore changes in some components of the response. According to our data, the inoculation with both F. graminearum and F. culmorum at the anthesis changed significantly the activities of superoxide dismutase (SOD) and guaiacol peroxidase (POD) enzymes, as well as the glutathione transferase (GST) activity in the flag leaves of the selected wheat lines approx. two weeks later after the infection. In silico approach supported the expressional up-regulation of various GST genes upon Fusarium infection. Based on our results, GST sequences TaGSTF26 and TaGSTU120 were among the series of important stress response genes, which were transcriptionally up-regulated, thus possibly playing a role in the systemic response to Fusarium infection, where TaGSTF26 might have an important role in the successful defence. These GSTs can serve as effective markers of the detoxification process for breeders and plant protection in the future.