Meeting Abstract
Nasonia is a genus with four species of parasitoid wasp that can be crossed in the laboratory, producing hybrids that demonstrate varying levels of reproductive isolation between these species. Previous work has shown that F2 hybrid males of crosses between Nasonia vitripennis and N. giraulti suffer >90% mortality during development when their genotype (N. vitripennis or N. giraulti) at a single nuclear locus doesn’t match their mitochondrial genotype. Due to this pattern of mismatched nuclear and mitochondrial genotypes, we have hypothesized that the mortality is due to deficiencies in metabolic physiology. Unfortunately, the small number of surviving hybrids makes it difficult to assess experimentally any potential mechanisms of this mortality. All male Hymenoptera are haploid so any effect of dosage cannot be measure, however F1 female hybrids (diploids that are heterozygous for each species’ alleles) don’t suffer this mortality. Despite this, preliminary data on F1 females indicates that they have a lower mitochondrial O2 consumption rate than either parent species. We will present mortality and physiological data based on crosses of these two species in which we generate female F1 hybrids and F2 backcross hybrids that are either heterozygous or homozygous for the mortality inducing genotype. This initial data will allow us to begin dissecting the mechanism of hybrid mortality in Nasonia and may provide a more tractable experimental system for studying mitochondrial physiology in these hybrids.
