Spotted Lanternfly Feeding Induces Systemic Defense Responses in Grapevines

Area of Science:

• Plant Science
• Entomology
• Agriculture

Background:

• The invasive spotted lanternfly (Lycorma delicatula) poses a significant threat to vineyards, impacting grape yield and plant health.
• Understanding grapevine immune responses to spotted lanternfly feeding is crucial for developing effective management strategies.

Purpose of the Study:

• To evaluate the systemic grapevine responses to spotted lanternfly feeding under various insect densities and feeding durations.
• To assess the impact of feeding on grapevine physiology and the subsequent suitability of the host for the insect.

Main Methods:

• Potted Vitis vinifera (Cabernet Franc) vines were infested with varying numbers of adult spotted lanternflies (0, 5, 10, 15) for different durations (1-29 days).
• Leaf tissues were analyzed for chlorophyll, polyphenol oxidase (PPO), peroxidase (POX), protein, total phenolics, and condensed tannins.
• Bioassays were conducted to measure spotted lanternfly survival and weight gain on previously infested vines.

Main Results:

• High-density, prolonged feeding (15 insects, 21-29 days) led to decreased chlorophyll content.
• Polyphenol oxidase (PPO) activity increased with higher insect densities and longer feeding durations, while peroxidase (POX) activity showed a delayed increase and subsequent decline.
• Leaf protein and phenolic concentrations increased significantly under prolonged, high-density infestation, and lanternfly survival and weight gain were reduced on previously infested vines.

Conclusions:

• Prolonged and high-density spotted lanternfly feeding induces coordinated, time- and density-dependent systemic grapevine defenses.
• These induced defenses contribute to reduced host suitability, suggesting a plant-mediated resistance mechanism.
• Further research is needed to elucidate the specific defense mechanisms and their variability across different grapevine cultivars.