Does Kin Recognition and Sib-Mating Avoidance Limit the Risk of Genetic Incompatibility in a Parasitic Wasp?

Abstract

BackgroundWhen some combinations of maternal and paternal alleles have a detrimental effect on offspring fitness, females should be able to choose mates on the basis of their genetic compatibility. In numerous Hymenoptera, the sex of an individual depends of the allelic combination at a specific locus (single-locus Complementary Sex Determination), and in most of these species individuals that are homozygous at this sexual locus develop into diploid males with zero fitness.Methods and FindingsIn this paper, we tested the hypothesis of genetic incompatibility avoidance by investigating sib-mating avoidance in the solitary wasp parasitoid, Venturia canescens. In the context of mate choice we show, for the first time in a non-social hymenopteran species, that females can avoid mating with their brothers through kin recognition. In “no-choice” tests, the probability a female will mate with an unrelated male is twice as high as the chance of her mating with her brothers. In contrast, in choice tests in small test arenas, no kin discrimination effect was observed. Further experiments with male extracts demonstrate that chemical cues emanating from related males influence the acceptance rate of unrelated males.ConclusionsOur results are compatible with the genetic incompatibility hypothesis. They suggest that the female wasps recognize sibs on the basis of a chemical signature carried or emitted by males possibly using a “self-referent phenotype matching” mechanism.

Host-Parasitoid Dynamics and the Success of Biological Control When Parasitoids Are Prone to Allee Effects

“…Some of the parasitoid adaptations for attracting mates (pheromone marking, reproductive aggregation) may be less efficient at low densities [24], [58], making density dependent. Moreover, female parasitoids sometimes display mate choice, tending to select non-kin individuals [59]. In small groups, males are more likely to be kin, and females may choose not to mate at all if they only encounter kin males [60], [61]; in our model this would be seen as a relative increase in .…”

Genetic incompatibility drives mate choice in a parasitic wasp

“…Kin recognition by olfactory cues has been described in a few insect species (e.g. [20-22]) and inbreeding avoidance is certainly an important measure in reducing the probability with which a matched mating is likely to occur [16]. In bottlenecked populations however, even unrelated individuals become likely to share a sex determining allele.…”

Monogeny, a neglected mechanism of inbreeding avoidance in small populations of gall midges

“…Haplodiploid insects have been proposed to suffer less from inbreeding than diploid insects, because of purging of deleterious recessive alleles in haploid males (Borgia, 1980). Females in some other hymeopteran species, such as Bracon hebetor Say (Ode et al, 1995), Venturia canescens Gravenhorst (Metzger et al, 2010), and the bumblebee Bombus terrestris L. (Whitehorn et al, 2009), are able to recognize their relatives and avoid mating or show reluctance to mate with them. Hence, these insects often exploit other reproductive strategies to reduce the likelihood of sib mating.…”