|Hulcr, Jiri - University Of Florida|
|Kasson, Matthew - West Virginia University|
|Ploetz, Jill - University Of Florida|
|Eskalen, Akif - University Of California|
|Geiser, David - Pennsylvania State University|
|Freeman, Stanley - Volcani Center (ARO)|
|Rooney, Alejandro - Alex|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 11/7/2014
Publication Date: 11/7/2014
Citation: O'Donnell, K., Sink, S.L., Hulcr, J., Kasson, M.T., Ploetz, J.N., Eskalen, A., Geiser, D.M., Freeman, S., Cosse, A.A., Rooney, A.P. 2014. Evolution of the Fusarium – Euwallacea mutualism and their cophylogenetic history [abstract].
Technical Abstract: This research was conducted to characterize the genetic diversity of wood-boring ambrosia beetles in the genus Euwallacea (Coleoptera: Curculionidae: Scolytinae) and the Fusarium fungi they cultivate for food. Native to Asia, five different infestations of these economically destructive mutualists have been introduced into the United States. These exotic fungus-farming beetles currently pose a significant threat to avocado production, urban landscape trees and forested areas worldwide. Twelve phylogenetically distinct ambrosia fusaria and eight Fusarium-farming Euwallacea species were identified based on collections from the United States, Australia and Sri Lanka. Moreover, four of the five Euwallacea spp. appear to have been introduced into the United States just within the past decade. Cophylogenetic analyses indicated that the Euwallacea beetles have switched Fusarium symbionts multiple times during the evolution of this 20 million year old mutualism. Surprisingly, three collections of a Euwallacea sp. from Miami, Florida shared an identical cytochrome oxidase subunit 1 allele with E. validus, suggesting introgressive hybridization between these species. Results of the present study highlight the importance of understanding the potential for and frequency of host-switching between Euwallacea and the fusaria they cultivate for food, given that these shifts may bring together more virulent and aggressive combinations of these invasive mutualists. Results of the present study should help inform quarantine officials and agricultural scientists of each species’ genetic diversity, host range and geographic distribution so that these economically destructive pests and pathogens can be monitored using molecular markers such as those developed in this study.