Data from: Population genetics of Wolbachia-infected, parthenogenetic and uninfected, sexual populations of Tetrastichus coeruleus (Hymenoptera: Eulophidae).

Wolbachia are endosymbiotic bacteria known to manipulate the reproduction of their hosts. These manipulations are expected to have consequences on the population genetics of the host, such as heterozygosity levels, genetic diversity and gene flow. The parasitoid wasp Tetrastichus coeruleus has populations that are infected with parthenogenesis-inducing Wolbachia and populations that are not infected. We studied the population genetics of T. coeruleus between and within Wolbachia-infected and uninfected populations, using nuclear microsatellites and mitochondrial DNA. We expected reduced genetic diversity in both DNA types in infected populations. However, migration and gene flow could introduce new DNA variants into populations. We therefore paid special attention to individuals with unexpected (genetic) characteristics. Based on nuclear and mitochondrial DNA, two genetic clusters were evident: a thelytokous cluster containing all Wolbachia-infected, parthenogenetic populations and an arrhenotokous cluster containing all uninfected, sexual populations. Nuclear and mitochondrial DNA did not exhibit concordant patterns of variation, although there was reduced genetic diversity in infected populations for both DNA types. Within the thelytokous cluster, there was nuclear DNA variation, but no mitochondrial DNA variation. This nuclear DNA variation may be explained by occasional sex between infected females and males, by horizontal transmission of Wolbachia, and/or by novel mutations. Several females from thelytokous populations were uninfected and/or heterozygous for microsatellite loci. These unexpected characteristics may be explained by migration, by inefficient transmission of Wolbachia, by horizontal transmission of Wolbachia, and/or by novel mutations. However, migration has not prevented the build-up of considerable genetic differentiation between thelytokous and arrhenotokous populations.

沃尔巴克氏体（Wolbachia）是一类已知可操控宿主生殖活动的内共生细菌，这类操控行为会对宿主的种群遗传学特征产生诸多影响，包括杂合度水平、遗传多样性与基因流。寄生蜂泰斯长尾小蜂（Tetrastichus coeruleus）存在两类种群：一类感染了可诱导孤雌生殖的沃尔巴克氏体，另一类则未被感染。本研究借助核微卫星（nuclear microsatellites）与线粒体DNA（mitochondrial DNA），对感染与未感染沃尔巴克氏体的种群之间以及种群内部的泰斯长尾小蜂种群遗传学特征展开了研究。我们最初推测感染种群的两类DNA的遗传多样性均会降低。然而，迁移与基因流可能会为种群引入新的DNA变异体，因此我们对携带非预期遗传特征的个体给予了特别关注。基于核DNA与线粒体DNA的分析结果，可明确区分两个遗传聚类群：一个为产雌孤雌生殖聚类群，包含所有感染沃尔巴克氏体的孤雌生殖种群；另一个为产雄孤雌生殖聚类群，包含所有未被感染的有性生殖种群。尽管两类DNA在感染种群中均表现出遗传多样性降低的特征，但核DNA与线粒体DNA的变异模式并不一致。在产雌孤雌生殖聚类群内部，存在核DNA变异，但无线粒体DNA变异。这类核DNA变异可通过以下几种机制解释：感染雌蜂与雄蜂之间的偶发性有性生殖、沃尔巴克氏体的水平传播，以及/或者新发突变。部分来自产雌孤雌生殖种群的雌蜂未被感染，且/或在微卫星位点上呈杂合状态。这些非预期特征可通过迁移、沃尔巴克氏体的低效传播、水平传播，以及/或者新发突变来解释。然而，迁移并未阻止产雌孤雌生殖种群与产雄孤雌生殖种群之间形成显著的遗传分化。