Wheat gluten proteins are decisive for the industrial properties of flour, so alterations resulting from grain infection with Fusarium graminearum produce changes in the glutenin content that affect the baking properties. This work analyzes the high-molecular-weight glutenin changes from wheat flour with different degrees of F. graminearum infection at field, since these proteins are determinant for the quality properties of flour. Wheat cultivars-on field trials-infected with F. graminearum isolates of diverse aggressiveness showed severity values between 9.1 and 42.58% and thousand kernel weight values between 28.12 and 32.33 g. Negative correlations between severity and protein content and positive correlations between yield and protein content were observed, employing reversed-phase high-performance liquid chromatography and polyacrylamide gel electrophoresis. Furthermore, the protein signal changes were in agreement for both methodological approaches. Also, the degree of disease observed and the protein changes on infected wheat cultivars varied in relation with the aggressiveness of the isolate responsible for the infection. The principal component analysis showed a close arrangement among protein values obtained by HPLC. For each cultivar, two principal components were obtained, which explained 80.85%, 88.48%, and 93.33% of the total variance (cultivars Sy200, AGP Fast, and Klein Tigre respectively). To our knowledge, the approaches employed for the analysis of protein changes according to the degree of disease, as well as the thorough statistical analysis, are novel for the study of Fusarium Head Blight.
Keywords: Aggressiveness; Fungal infection; Gluten proteins; HPLC analysis; SDS-PAGE analysis; Whole grain flour.