Peps, Pathogens, and Pests: Challenges and Opportunities for Usage of Pep Signaling in Sustainable Farming

Peps (plant elicitor peptides) are important messengers in plant stress responses and activate plant immune as well as in some cases anti-predation defense responses. These signaling molecules have predominantly been studied in their roles in biotic interactions. While early research focused on model species’ Peps and Pep receptors (PEPRs), Pep signaling components are now often investigated in crop species. Much of this interest owes to a desire to use Peps in sustainable agriculture as an alternative to applying environmentally harmful pesticides. Peps, as polypeptides native to plant species, are easily degraded in the environment after treatment and are native to the crop plant to which they are applied; factors favoring their benign effects on the environment. However, there are challenges to overcome in utilizing Peps as tools in agriculture. This chapter will discuss what problems must be overcome to effectively make use of Pep signaling in sustainable agriculture, such as incorporating Peps into pest management strategies and disease mitigation. Activating Pep signaling can only be beneficial when it is an effective pathway for dealing with a given biotic threat(s). Future directions for research into Peps will be discussed in the context of overcoming these challenges and the opportunities for using Peps in different applications in sustainable agriculture.