ARS | Publication request: Retrospective analysis of the successful establishment of a biocontrol agent based upon microsatellite data

Submitted to: Evolutionary Biology Meeting at Marsielle
Publication Type: Proceedings
Publication Acceptance Date: June 7, 2012
Publication Date: September 18, 2012
Citation: Bon, M., Marcari, V., Hoelmer, K.A., Coutinot, D., De Biase, A. 2012. Retrospective analysis of the successful establishment of a biocontrol agent based upon microsatellite data. Evolutionary Biology Meeting at Marsielle. 16th Evolutionary Biology Meeting, September 18-21, 2012, Marseille, France, p. 33.

Technical Abstract: The tarnished plant bug Lygus lineolaris is an important pest of cotton and many other crops in North America. Since the 1970s prevalence of insecticide resistant populations coupled with environmental concerns have raised interest in classical biological control of this pest. Peristenus digoneutis, a western Palearctic nymphal parasitoid of Lygus lineolaris, was introduced from Europe repeatedly between 1979 and 1984 into New Jersey (USA). It is now successfully established in 11 northeastern U.S. states and three Canadian provinces. Most of our current knowledge about introduction and colonization pathways of the biocontrol agent relies on historical records and observational data. Established populations resulted following successive introductions of populations from genetically differentiated ancestral origins in Austria and France. Several questions remain to be answered regarding the geographic origin and the genetic composition of the populations that successfully established. In recent years new model-based methods, such as approximate Bayesian computation, have allowed researchers to extract historical information from molecular data, which has fundamentally transformed the understanding of processes influencing biological invasions and has made it possible to answer such questions. As a prerequisite, parasitoid populations must be genotyped with microsatellite loci. At the start of the project in 2012, microsatellites were identified using the new pyrosequencing based-technology. Primers were designed in 48 microsatellite loci targeting various microsatellite repeats with varying proportions of each repeat in this taxon. Polymorphism of the validated loci multiplexed in several sets is being assessed first in the established P. digoneutis populations, and later on in the historical populations. Here, we describe the first microsatellites developed for this parasitoid and the preliminary results of our retrospective study.