Fusarium head blight (FHB) is one of the main severe diseases of cereals, including durum wheat (Triticum turgidum subsp. durum). Polyphenols are secondary metabolites that could act as stress protecting agents, playing a significant role in plant resistance against plant pathogens. Pigmented wheat genotypes have flavonoids-rich kernels, due to the presence of anthocyanins in the pericarp or in aleurone layer. Different researchers studied the plant-pathogen interaction between pigmented cereals and Fusarium spp., causal agents of FHB, but there is a lack of knowledge on the disease resistance level of pigmented durum wheats and about phenolic metabolism of durum wheat during FHB infection.

The purpose of this work was to evaluate the resistance level of a pigmented durum wheat genotype (Purple Durum) and to analyze the phenolic metabolism during F. graminearum infection. FHB assay was carried out by artificial tip inoculation into spikes, in controlled environment, by using 3 durum wheat cultivars: Svevo (susceptible), DBC 480 (resistant), and Purple Durum (pigmented). Concerning a whole disease evaluation, different resistance components were considered: type II resistance (disease severity %) and type IV resistance (percentage of Fusarium Damaged Kernels, FDK), in association to the health status index (flag leaf Nitrogen Balance Index, NBI) and the production indexes (number and weight of grains produced). The data shown that Purple Durum was a susceptible variety and that Total Phenolics Content (TPC) was higher in the infected spikes of Purple Durum compared to untreated control. Princincipal Component Analysis (PCA) reveals a correlation between TPC and the most important disease indexes (severity %, AUDPC, FDK and kernel weight). To better understand the relationship between phenolic metabolism and Fusarium spp. infection in durum wheat, further analysis has already been planned (i.e.: quantification of the phenolic compounds and differential expression of genes).