Insect digestive enzymes as a target for pest control

The continual need to increase food production necessitates the development and application of novel biotechnologies to enable the provision of improved crop varieties in a timely and cost-effective way. Plants and herbivores have been co-evolving for thousands of years, and as a result, plants have defence mechanisms that offer protection against many herbivores/predators. Plant proteinase inhibitors (PIs), which play a potent defensive role against predators and pathogens, are natural, defense-related proteins often present in seeds and induced in certain plant tissues by herbivory or wounding. This review describes the main classes of proteinase inhibitors and proteinases, their distribution and localization, general properties, and their main functions. Possible applications utilities for the PI and proteolytic enzymes in plant biotechnology have been reviewed.