Genetic variability of arrhenotokous and thelytokous Venturia canescens (Hymenoptera)

The ichneumonid wasp Venturia canescens (Hymenoptera) has been studied extensively for foraging behaviour and population dynamics of sexually (arrhenotokous) and parthenogenetically (thelytokous) reproducing individuals. Here we report the development of a set of microsatellite markers for V.canescens and use them to show that arrhenotokous individuals have more genetic variability than thelytokous ones, which are even homozygous for all tested loci. Crosses between arrhenotokous individuals suggested one marker, Vcan071, to be linked with the Complementary Sex Determiner (CSD) locus and one, Vcan109, with the Virus Like Protein (vlp-p40) locus. The genome size of V. canescens was estimated to be 274-279 Mb. We discuss how both reproductive modes can give rise to the observed genetic variability and how the new markers can be used for future genetic studies of V. canescens.