Transcriptome Profiling of Defense Genes of Susceptible and Resistant Wheat Infected by Fusarium graminearum

Fusarium head blight (FHB) caused by Fusarium graminearum has posed a serious threat to both wheat and barley production worldwide, reducing not only the quantity but also the grain quality. Resistant varieties are the best and most effective way to control this destructive disease, but the molecular mechanisms leading to FHB resistance are still unclear. Transcriptional profiling was conducted for the spring wheat cultivars “Sumai 3” (resistant) and “Caledonia” (susceptible). The gene expressions at 6, 12, 24, 36, 48, 72, 144 h after inoculation (hai) with Fusarium graminearum were used to trace possible defence mechanisms and associated genes. A comparative qPCR was carried out for selected genes; such as UDP-glucosyltransferase, glucosidase, chitinase, thaumatin-like protein, peroxidase and methyltransferase, to analyse the respective expression patterns in “Sumai 3” and “Caledonia”. Overall, the transcriptome profiling showed that the putative defense genes of resistant cultivars were more expressed compared with the susceptible one at different time intervals. Moreover, the transcript levels of the defense genes were induced as early as 6 hai and most peaked at 72hai. The defense genes and their relationship to possible defenses from fusarium infection and toxin production will be discussed.