Degradation of gluten proteins by Fusarium species and their impact on the grain quality of bread wheat

Abstract
The protein quality of wheat, the most important crop worldwide, is affected by the presence of fungi, mainly those belonging to the Fusarium genus. The aim of this study is to analyze the effects of Fusarium spp. on ground wheat grains quality by measuring gluten strength and quantifying the gliadin/glutenin content. A total of 23 Fusarium spp. isolates and two bread wheat (Triticum aestivum L.) genotypes with contrasting baking quality were used in the investigation. The results of SDS sedimentation test (SDSS) revealed that the presence of Fusarium species significantly affected the gluten strength negatively; while F. pseudograminearum and F. graminearum are the species that predominantly affected the SDSS values. Principal component analysis of gluten composition showed that the effect of Fusarium species on gluten composition depended on the wheat genotypes analyzed. Cluster analysis revealed that all the Fusarium species used as inoculum produced severe effects on grain quality and gluten composition on both the genotypes. In summary, our results showed that the presence of Fusarium spp. impaired storage proteins affecting the wheat dough properties. Therefore, constant monitoring is necessary to reduce the presence of Fusarium in the food chain for reducing the negative potential impact on bread quality.