Boll Weevil (Anthonomus grandis grandis Boheman) Population Genomics As a Tool for Area-Wide Management

Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), commonly known as the boll weevil (BW), is a major pest of cotton across the Americas. Despite the success of the US Boll Weevil Eradication Program, the BW remains a significant threat to cotton production in southern Texas, and the species is arguably the most important cotton pest in Central and South America. Control of this species is complicated by the existence of morphologically and genetically similar non-pest variants, its ability to overwinter in a state of diapause, and a lack of knowledge about the species’ population dynamics, which contribute to yearly recurrent invasions of areas where control measures are applied. Thus, there is a need to develop informative diagnostic methods using genome-wide markers that can (1) discern pest and non-pest variants, (2) delimit and distinguish between populations, and (3) elucidate patterns of insect movement across space and time. We have previously used double digest restriction site-associated DNA sequencing (ddRADseq) to resolve the population genomic structure of the BW in northern Mexico and identified gene flow among populations in Mexico and those occurring in southern Texas. In order to more fully resolve the global population genomic structure of this species, we are now expanding this research to other populations occurring elsewhere in Mexico and Texas, in addition to resampling the areas from the previous year of study. Furthermore, we will include Anthonomus specimens collected from wild cotton in Arizona and Anthonomus specimens collected from cotton growing areas in Peru (A. vestitus) and tentatively Argentina. These methods will improve the current diagnostic capacity for distinguishing between Anthonomus variants and in identifying the origin of recent introductions and infestations.