Transgenic Expression of Lytic Peptides in Food and Feed Crops to Control Phytopathogens and Preharvest Mycotoxin Contamination

Transgenic crops are widely cultivated in several countries to control crop losses due to insects and weeds. However, disease resistant transgenic crops that can withstand infections due to fungal and bacterial pathogens are not yet available due to several reasons. The primary reasons are 1) host plant-pathogen interaction is a very complex phenomenon and it is often crop/variety or pathogen/strain specific.; 2) natural antimicrobial proteins and peptides are subject to digestion by protcases, lack specificity and may be toxic to non-target plant and animal species; 3) large scale production of antimicrobial proteins and peptides are very expensive and 4) microbial pathogens can develop resistance to natural proteins and peptides. Recent advances in combinatorial chemistry and automated peptide synthesis have paved the way for rational design of stable, potent, and novel synthetic peptides with target-specific biological activity. Some of these lytic synthetic peptides have been already expressed in transgenic plants with varying degrees of success towards control of phytopathogens including some fungal pathogens that produce mycotoxins. This review gives a brief account of recent developments regarding the use of lytic peptides in transgcnic crops to control yield losses due to pathogens and mycotoxin contamination.