Genetic analysis reveals lack of geographic or climatic isolation in global Halyomorpha halys populations, indicating human-mediated dispersal drives widespread invasion.
Key Points
To evaluate global mitochondrial genetic diversity in Halyomorpha halys and determine whether invasion dynamics are driven by geographic distance, environmental factors, or human-mediated transport.
Assembled a mitochondrial COI sequence dataset (N=1,039) from 15 countries across native and introduced ranges, incorporating 119 newly sequenced specimens.
Conducted genetic diversity analyses, reconstructed haplotype networks, and performed Mantel tests to assess isolation by distance (IBD) and isolation by environment (IBE).
Identified 65 haplotypes with two dominant lineages (H1 and H3); native ranges exhibited high diversity, whereas introduced regions generally showed founder effects, except in Greece and Belgium which showed high diversity and positive Fu's Fs values indicative of multiple introductions.
Mantel tests detected no statistically significant correlation between genetic distance and geographic distance or climatic dissimilarity (p > 0.05), consistent with human transport overriding natural biogeographic patterns.