Skip to main content
ARS Home » Southeast Area » Gainesville, Florida » Center for Medical, Agricultural and Veterinary Entomology » Insect Behavior and Biocontrol Research » Research » Publications at this Location » Publication #396613
Research Project: Managing Invasive Weeds and Insect Pests Using Biologically-Based Methods

Location: Insect Behavior and Biocontrol Research

Title: Spatial and host related genomic variation in partially sympatric cactophagous moth species

Author
item POVEDA-MARTINEZ, D - Fuedei
item VARONE, L - Fuedei
item CORONA, M.F - Fuedei
item HIGHT, S - Retired ARS Employee
item LOGARZO, G - Fuedei
item HASSON, E - Consejo Nacional De Investigaciones Científicas Y Técnicas(CONICET)

Submitted to: Molecular Ecology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/11/2021
Publication Date: 10/18/2021
Citation: Poveda-Martinez, D., Varone, L., Corona, M., Hight, S., Logarzo, G., Hasson, E. 2021. Spatial and host related genomic variation in partially sympatric cactophagous moth species. Molecular Ecology. 31(1):356-371. https://doi.org/10.1111/mec.16232.
DOI: https://doi.org/10.1111/mec.16232

Interpretive Summary: The Argentine cactus moth, Cactoblastis cactorum, is well documented as an ecomonic pest for cactus production in South America. Since its accidental introduction into Florida, this invasive pest threatens both the ecological diversity of important native cacti as well as economic production of prickly pear in North America. In collaboration with Argentine scientists, a scientist at USDA-ARS, Center of Medical, Agricultural and Veterinary Entomology, Gainesville, Florida, examined the genetic differences between different species of a cactus moths in Argentina. Host plant and geographic differences were related to separation of most species, however several species including C. cactorum revealed hybrid populations that could be related to broader host ranges. Such an increase in host range has the potential to result in greater negative impacts from this invasive species.

Technical Abstract: Surveys of patterns of genetic variation in natural sympatric and allopatric populations of recently diverged species are necessary to understand the processes driving intra-and interspecific diversification. The South American moths Cactoblastis cactorum, Cactoblastis doddi and Cactoblastis bucyrus are specialized in the use of cacti as host plants. These species have partially different geographic ranges and differ in patterns of host plant use. However, there are areas that overlap, particularly, in northwestern Argentina, where they are sympatric. Using a combination of genome-wide SNPs and mitochondrial data we assessed intra and interspecific genetic variation and investigated the relative roles of geography and host plants on genetic divergence. We also searched for genetic footprints of hybridization between species. We identified three well delimited species and detected signs of hybridization in the area of sympatry. Our results supported a hypothetical scenario of allopatric speciation in the generalist C. cactorum and genetic interchange during secondary geographic contact with the pair of specialists C. bucyrus and C. doddi that probably speciated sympatrically. In both cases, adaptation to new host plants probably played an important role in speciation. The results also suggested the interplay of geography and host plant use as drivers of divergence and limiting gene flow at intra and interspecific levels.