Population genetic structure and demographic history of Spodoptera frugiperda (Lepidoptera: Noctuidae): implications for insect resistance management programs

Population genetic structure and demographic history of Spodoptera frugiperda (Lepidoptera: Noctuidae): implications for insect resistance management programs

Spodoptera frugiperda is a destructive pest that often imposes difficult management due to its high polyphagy and rapid insecticide resistance evolution. Knowledge of species diversification, population structure, and host preference can aid efforts to manage pest populations. In this study, we investigated the patterns of hybridization, genetic structure, and gene flow in S. frugiperda populations, discussing how we can apply this knowledge to insect resistance management programs in South America. 

We conclude that high levels of population admixture, including between corn‐ and rice‐strains, were found in sampled populations. We showed that S. frugiperda immigrants will not necessarily cause an increase in LC₅₀ upon arrival in a new location but will assure the constant presence of resistance alleles in the area. Increases in LC₅₀ largely depend on the local pesticide management adopted in the areas. Our results indicate that pesticide resistance management must be adopted on a local or small regional scale