Specificity of α-amylase and trypsin inhibitor proteins in wheat against insect pests

Abstract

Insect pest infestation is a major cause of crop loss during storage. However, the use of chemical pesticides results in environmental pollution and may cause allergic reactions when consumed. The inhibition of insect digestive enzymes with potential proteinaceous or non-proteinaceous inhibitors could be an effective alternative approach to control infestations. In the present study, we evaluated the specificity of the inhibitor proteins α-amylase and trypsin in 54 genotypes of wheat (Triticum aestivum) against the digestive amylases of the wheat storage insects Rhyzopertha dominica and Tenebrio molitor, human salivary amylase, porcine pancreatic amylase and bovine trypsin. We found that these proteinaceous inhibitors vary in their expression between genotypes, and identified six genotypes in which inhibitor activity was high against the insects but low against human salivary and pancreatic amylase. These findings will significantly aid the selection of wheat genotypes with potential resistance against storage insects and minimum health concerns for humans.