Genomic patterns of strain-specific genetic structure, linkage, and selection across fall armyworm populations

• DOI: 10.1186/s12864-025-11214-8
• Publication Date: 2025-02-07T05:46:02Z
• Authors: Ashley E. Tessnow; Rodney N. Nagoshi; Robert L. Meagher; Todd M. Gilligan; Ben M. Sadd; Yves Carrière; Holly N. Davis; Shelby J. Fleischer; Kelly Richers; John C. Palumbo; Patrick Porter; Jose Carlos Verle...; Gregory A. Sword
• Keywords: Population genomics; Population Genetics

Abstract Background Molecular genetic approaches have become vital to understanding the evolutionary processes that act on insect pest populations. From mapping development of resistance monitoring and predicting movement, genomic tools can inform enhance management programs. Here, we used whole genome sequencing population genomics unravel novel patterns structure, linkage, selection across a notorious agricultural pest, fall armyworm. Results Our data strongly support existence two genetically distinct strains armyworm in North America, which previously been referred as C-strain R-strain. Although these diverged genetically, find differentiation is not uniform genome. The Z-chromosome appears drive divergence between with high levels linkage observed this chromosome. We also show region containing circadian clock gene implicated allochronic reproductive isolation under strain-specific selection. indicates differ their geographic distributions exhibit sub-structuring indicative unique dispersal patterns. provide first evidence for nuclear major overwintering populations US. Finally, our reveal population-specific regions putative insecticide alleles, could relate biogeography. Conclusions results dyad US, genetically-distinct differing patterns, signatures likely involved resistance. These differences should be considered when devising implementing strategies.