Phylogeography of the Recent Expansion of Helicoverpa armigera (Lepidoptera: Noctuidae) in South America and the Caribbean Basin

Abstract

The Old World bollworm, Helicoverpa armigera (Hübner), is one of the most destructive agricultural pests worldwide. It was first recorded in Brazil in 2013, yet despite this recent introduction, H. armigera has spread throughout much of Latin America. Where H. armigera has become established, it is displacing or hybridizing with the congeneric New World pest Helicoverpa zea. In addition to the adaptive qualities that make H. armigera a megapest, such as broad range pesticide resistance, the spread of H. armigera in the New World may have been hastened by multiple introductions into South America and/or the Caribbean. The recent expansion of the range of H. armigera into the New World is analyzed herein using mtDNA of samples from South America, the Caribbean Basin, and the Florida Peninsula. Phylogeographic analyses reveal that several haplotypes are nearly ubiquitous throughout the New World and native range of H. armigera, but several haplotypes have limited geographic distribution from which a secondary introduction with Euro-African origins into the New World is inferred. In addition, host–haplotype correlations were analyzed to see whether haplotypes might be restricted to certain crops. No specialization was found; however, some haplotypes had a broader host range than others. These results suggest that the dispersal of H. armigera in the New World is occurring from both natural migration and human-mediated introductions. As such, both means of introduction should be monitored to prevent the spread of H. armigera into areas such as the United States, Mexico, and Canada, where it is not yet established.

Global FAW population genomic signature supports complex introduction events across the Old World

“…Indeed, global movements of invasive pests, exemplified by the spread of FAW, as well as the multiple introductions of H. armigera into the South American continent 15 and various Caribbean nations 121 from Asia 10,14 and various Old World regions 3 , are timely reminders of the need for global coordination of enhanced biosecurity preparedness strategies that build on advancement in genomic research. The potential negative impacts of introductions of alien species include introgression of genetic traits to local species through hybridisation 10,13,14,16,28 .…”

Biological Control Potential and Drawbacks of Three Zoophytophagous Mirid Predators against Bemisia tabaci in the United States

“…Further work to facilitate their establishment and retention in tomato plantings or in the environs of the field would also help growers prepare for imminent pest threats. Important lepidopteran pests such as T. absoluta and H. armigera are rapidly spreading and threaten tomato production systems in North America, the Caribbean region, and elsewhere [ 63 , 64 ]. N. tenuis has been shown to successfully switch from whiteflies to preying on T. absoluta soon after its arrival in the Mediterranean [ 65 ].…”

Inheritance of Bacillus thuringiensis Cry2Ab2 protein resistance in Helicoverpa zea (Lepidoptera: Noctuidae)

“…The differences in Cry2Ab2 inheritance of these two related species may contribute to the greater susceptibility in the field of H. armigera to Cry2Ab2 protein compared to H. zea . Currently, H. armigera has invaded into Brazil and US territories, 55–58 and it is likely that incursions of H. armigera will continue in the New World. The complex of these two related species in the field will challenge the resistance management for Bt crops.…”