Baking quality of wheat flour affected by cereal aphids

Flour from grains originating from plants infected artificially with cereal aphids were analyzed for glutenin and gliadin and total protein content, using Size Exclusion HPLC. Wheat plants were caged at the beginning of stem elongation. Cages were treated with 0.1 % methyl parathion. One week later, the caged plants were artificially infected with 5 aptera individuals of Metopolophium dirhodum, Diuraphis noxia, Sitobion avenae and Rhopalosiphum padi. It was found that aphid infection had significant effect on the glutenin and gliadin content, the total protein content and the gliadin/glutenin ratio. Both the glutenin and gliadin content was significantly higher in the seeds harvested from aphid infected plants. However, the gliadin/glutenin ratio was significantly lower in wheat flour prepared from aphid infected plants than in those from uninfected control. The most significant decrease in gliadin/glutenin ratio was caused by M. dirhodum, D. noxia, S. avenae infection followed by R. padi at high-abundance. As the gliadin/glutenin ratio was significantly lower in flours made from aphid infected wheat seeds, it may be suggested, that aphid feeding results in decreased bread making quality of wheat flour.