Trichoderma elicitors induce Local and Systemic Defense mechanisms

Abstract

The increased use of antimicrobials in agricultural practices have shown detrimental effects on ecology and cause disease outbreaks due to resistant pathogenic strains. Currently, biological control agents are rising in popularity as an alternative to conventional chemicals to prevent these negative outcomes. Plant symbiont and mycoparasite Trichoderma is a well-known biological control agent that antagonizes disease agents directly and enhances the plants own defense response. In this study it was investigated how the elicitors produced by Trichoderma induced an increased defense response in the plant against pathogenic microbes. It was shows that Trichoderma induces local defense mechanisms such as calcium influx, MAPK cascades, callose deposition, ROS-related defense and polyphenol synthesis. On the other side, Trichoderma also induces systemic defense in plants along the SA, ET and JA pathways. Lastly, several Trichoderma elicitors are discussed and what is currently known about their mode of action in the host plant. These include, xylanase, chitinase, cellulase, Epl1, 6-PP and peptaibols.