English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Background  Thelytoky, the parthenogenetic development of females, has independently evolved in several insect orders yet the study of its mechanisms has so far mostly focussed on haplodiploid Hymenoptera, while alternative mechanisms of thelytoky such as polyploidy are far less understood. In haplodiploid insects, thelytoky can be encoded in their genomes, or induced by maternally inherited bacteria such as  Wolbachia  or  Cardinium . Microbially facilitated thelytoky usually results in complete homozygosity due to gamete duplication and can be reverted into arrhenotoky, the parthenogenetic development of males, through treatment with antibiotics. In contrast, genetically encoded thelytoky cannot be removed and may result in conservation of heterozygosity due to gamete fusion. We have probed the obligate thelytoky of the greenhouse thrips,  Heliothrips haemorrhoidalis  (Bouché), a significant cosmopolitan pest and a model species of thelytoky in the haplodiploid insect order Thysanoptera. Earlier studies suggested terminal fusion as a mechanism for thelytoky in this species, while another study reported presence of  Wolbachia ; later it was speculated that  Wolbachia  plays a role in this thrips’ thelytokous reproduction.    Results  By using PCR and sequence analysis, we demonstrated that global population samples of  H. haemorrhoidalis  were not infected with  Wolbachia, Cardinium  or any other known bacterial reproductive manipulators. Antibiotic treatment of this thrips did also not result in male production. Some individuals carried two different alleles in two nuclear loci,  histone 3  and  elongation factor 1 alpha , suggesting heterozygosity. However, the majority of individuals had three different alleles suggesting that they were polyploid. Genetic diversity across both nuclear loci was low in all populations, and absent from mitochondrial  cytochrome oxidase I , indicating that this species had experienced genetic bottlenecks, perhaps due to its invasion biology or a switch to thelytoky.    Conclusions  Geographically broad sampling and experimental manipulation revealed low genetic diversity, absence of  Wolbachia  but presence of three different alleles of nuclear loci in most analysed individuals of obligately thelytokous  H. haemorrhoidalis . This suggests that polyploidy may be involved in the thelytokous reproduction of this thrips species, and polyploidy may be a contributing factor in the reproduction of Thysanoptera and other haplodiploid insect orders.    Electronic supplementary material  The online version of this article (doi:10.1186/s12862-015-0304-6) contains supplementary material, which is available to authorized users.

Polyploidy versus endosymbionts in obligately thelytokous thrips