Summer 2024: Measuring the Effects of Toxins from Two Different Plant Families on grasshoppers

Project title: "Measuring the Effects, or Lack Thereof, of Toxins from Two Different Plant Families on the Spotted Bird Grasshopper"

Abstract: Insects are vital members of our ecosystems and are an important part of many food chains. They eat various plants that can have defense chemicals the plant produces in their tissues. These can vary in lethality based on the insect-plant relationship. In this study, we aim to identify the impact of this relationship on insects by looking at Solanaceous and Brassicaceous plant toxins when artificially fed to the Spotted Bird Grasshopper, Schistocerca americana. Solanaceous plants have chlorogenic acid (CGA) in their tissues, which has been identified to have insecticidal properties. Phenethyl isothiocyanate (PEI), found in Brassicaceous plants, similarly disrupt the insect-plant interactions. To measure the effects on fitness metrics of the Spotted Bird Grasshopper when fed CGA and PEI, we chose multiple concentrations for each chemical and fed it to the insects. During the experiment we measured multiple metrics of fitness and found that CGA lacked significant effect while PEI had significant effect on mortality and total weight change over the course of the experiment. The results of this study fill a gap of knowledge on the effects of these commonly found plant defense chemicals on members of our ecosystem that often go under-studied.

This research was conducted at The University of Texas at Arlington through the Ravenscraft lab, and was presented at the UT system LSAMP conference in El Paso, TX, as well as DISCOVER 2025 in Arlington, TX.