Plant herbivore interactions with varied herbivore intensity: the roles of plant defenses and nutrients

Evolutionary arms races found in plant-herbivore interactions are key examples of coevolution. Their ability to evolve as reciprocals to each other has given rise to various specific interactions. These interactions have produced a variety of defense and counter defense mechanisms from both sides. Adaptations to chemical and physical defenses in the form of counter defenses have enabled herbivores to specialize in their host plants. Ultimately this is trivial to the effectiveness of the host plant’s defense. My main inquiry was if there is some type of plant cost-benefit analysis for induced defenses and if there a threshold to which the plant defenses are no longer beneficial. I was also interested in the effects the induced plants have on beetle survival, focusing on reproduction. The field experiment used a plant-herbivore pair, Chrysochus auratus and its host plant Apocynum cannabinum as model organisms. The field experiment was conducted by exposing A. cannabinum to varying C. auratus densities and sampling the A.cannabinum defenses and measuring C.auratus reproduction.