Trichoderma-mediated plant resilience against insect herbivory

Trichoderma spp., are root endophytic fungi renowned for their plant-growth promoting and biocontrol properties. Some commercially available Trichoderma strains have demonstrated the ability to improve plant tolerance to abiotic stresses such as drought and salinity. They enhance nutrient uptake by increasing root length, improve plant photosynthetic efficiency, and protect plants against oxidative stress by priming plant oxidative responses. This defense priming primarily occurs through the upregulation of ROS scavenging enzymes and results in increased levels of plant defense metabolites such as proteinase inhibitors and polyphenols. We hypothesized that Trichoderma infection induces tomato plant (Solanum lycopersicum) defense metabolite levels which negatively affects insect herbivores such as the corn earworm caterpillar (Helicoverpa zea) feeding on these plants. In this presentation we discuss how two Trichoderma strains T. harzianum T-22 and T. longibrachtum improve tomato salt tolerance, increase tomato defense enzyme levels, and affect H. zea caterpillar growth. Our research has wide implications for how root endophytic fungi play an important role in improving abiotic and biotic stress tolerance in crops.