Giovanna Lemgruber Viol
Year: 2021
Faculty Advisor: Jennifer Thaler
Mentor: Julie Davis

“Effects on Withanolides on Insect Herbivory”

Project Summary:

Withanolides are secondary metabolites produced by plants of the Physalis genus, which includes the crops tomatillo, goldenberry, and groundcherry. Existing research indicates withanolides have anti-herbivory effects, but the potential to use them in pest control is understudied. In my research, we tested the hypothesis that the presence of withanolides on plant tissue will reduce insect herbivory and performance through reduced leaf area consumption and reduced insect weight gain. We placed T. ni larva in a sealed petri dish with a potato leaf disk that was either untreated, painted with withanolides (extracted in ethanol solvent), or painted with ethanol (control for solvent). We found plant tissue treated with withanolides had reduced insect herbivory and performance, supporting our hypothesis and suggesting withanolides may be a useful tool in controlling pests. In better understanding withanolides, we may be able to harness their anti-herbivory effects by breeding for withanolide production within Physalis species, or be able to extract and apply them. Future research is needed, especially in regards to assessing withanolide effects across plant and insect species.

My Experience:

During my internship, I gained a hands-on understanding of the scientific method, seeing and participating in the commitment to good methodology, data collection, and statistical analysis. I learned that it is a process with considerable challenges, especially when bracing through difficult data collection days and interpreting unexpected results. These challenges highlighted the importance of teamwork and communication in research groups. Being surrounded by people who are passionate and knowledgeable in the areas of entomology and ecology allowed me to be curious about these fields and gain a greater understanding and appreciation of them. Leaving this internship, I have a greater arsenal of experiences to guide my future plans. Wherever I end up, the scientific method will remain a close friend.