Spotted lanternfly feeding induces defense responses in grapevines
Research Poster Health & Life Sciences 2025 Graduate ExhibitionPresentation by Sukhman Singh
Exhibition Number 97
Abstract
Plants have evolved structural and biochemical defenses against insect herbivory, which can be constitutive or induced by insect feeding, affecting insect survival, growth, and reproduction. The spotted lanternfly (Lycorma delicatula; SLF), an invasive pest in the northeastern U.S. since 2014, poses a significant threat to vineyards. However, little is known about the defense mechanisms of grapevines against SLF feeding. This study investigates the defense responses of grapevine (Vitis vinifera; cultivar ‘Cabernet Franc’) to SLF feeding at different insect densities and feeding durations. We conducted density-dependent and time-course experiments using four SLF densities (0, 5, 10, and 15 insects per grapevine) and seven feeding durations (1, 3, 5, 7, 14, 21, and 29 days), with separate plant sets for each time point. We measured polyphenol oxidase (PPO) and peroxidase (POX) activity, total phenolic content, and SLF survival. Results showed that SLF feeding induced higher PPO activity at density 15 compared to controls at all time points, except day 5. POX activity was higher at density 15 after 5 and 7 days of feeding, but sharply decreased after 21 and 29 days, suggesting suppression due to SLF feeding. Total phenolic levels were also higher at density 15, particularly at 14 and 29 days. Reintroducing SLF to plants previously fed by density 15 showed higher mortality compared to those feeding on control plants. These findings provide insight into grapevine-SLF interactions, indicating that induced plant defenses at high insect densities can reduce SLF survival and growth, offering potential for pest management strategies.
Importance
Spotted lanternfly is an invasive insect pest in northeast United States since 2014 that feed on broad range of host plants including economically important grapevines. However, the information on the defense mechanisms employed by grapevine plants against spotted lanternfly feeding is limited. Our study investigates the defense enzymes and total phenolics content (defense compounds) in grapevine leaves in response to the spotted lanternfly feeding. Additionally, we looked at survival of spotted lanternfly on grapevines previously fed by spotted lanternfly. Our study provides insights into grapevine-spotted lanternfly interactions, offering potential for pest management strategies.