Evaluation of Volatile Organic Compounds from Spotted Lanternfly (Lycorma delicatula) Eggs Using Headspace Odor Sampling Methods

Abstract

The spotted lanternfly (SLF) is an invasive species native to China. It was first discovered in the United States in Pennsylvania in 2014. It is known to cause great economic damage by destroying various crops, specifically grape vines, and therefore, several efforts have been made to control and mitigate its spread from the Northeast. Canine detection is a useful detection tool; however, it is crucial to understand the volatile organic compounds emitting by this pest to better direct canine training paradigms to prevent false alerts and to understand potential volatile markers of importance indicative of this species. The purpose of this study is to address the gap in research regarding the volatile organic compound (VOC) profile of SLF to better inform pest control mitigation strategies. Instrumental analysis was performed utilizing SPME-GC/MS on cold-killed SLF eggs, dried crickets, and tree bark. Differences in detected VOCs within each sample set depicted distinctive odor profiles for each matrix tested. Storage of these samples also depicted VOC accumulation variation as a function of time, thereby providing implications for long-term storage and sample handling for these types of training aids in canine applications.

Keywords: Lycorma delicatula; canine detection; gas chromatography-mass spectrometry (GC/MS); odor profile; solid-phase micro-extraction (SPME); spotted lanternfly.

Figure 1

Sample vials containing (A) SLF eggs and (B) crickets with SPME fiber injected in the headspace.

Figure 2

Stacked bar graph representing the relative peak area response of the odor profiles of the SLF eggs, crickets, and bark upon initial sampling, day zero.

Figure 3

Venn diagram listing the primary and shared compounds from the SLF eggs, crickets, and bark.

Figure 4

Stacked bar graph representing the relative peak area response of the odor profiles of the SLF eggs and crickets over a 6-week sampling period.

Figure 5

Total VOC accumulation graph from each specimen, SLF eggs and crickets, across the 6-week sampling period. Error bars indicate the standard error of the mean.

Figure 6

Bar graph representing the concentration of dodecane and anisole in the frozen storage study (PPM).

Figure 7

PCA of the primary compounds from the SLF eggs across 6 weeks (top) compared to the primary compounds from the crickets across 6 weeks (bottom).

Figure 8

Stacked bar graph representing the relative peak area response of the odor profiles of the open and closed SLF eggs and crickets over a 6-week sampling period.

Figure 9

Total VOC accumulation graph from each specimen, open and closed SLF eggs and crickets, across the 6-week sampling period.

Figure 10

PCA of the primary compounds from the open egg and cricket samples across the 6 weeks (top) and the primary compounds from the closed egg and cricket samples (bottom).

Figure 11

VOC accumulation distributions for (A) SLF eggs and (B) crickets as a function of sample lid condition (c—closed, o—open).