Multiple Data Demonstrate That Bacteria Regulating Reproduction Could Be Not the Cause for the Thelytoky of Diglyphus wani (Hymenoptera: Eulophidae)

• Published in: Insects (Basel, Switzerland) Vol. 13; no. 1; p. 9
• Main Authors: Du, Sujie, Ye, Fuyu, Wang, Qijing, Liang, Yongxuan, Wan, Weijie, Guo, Jianyang, Liu, Wanxue
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 22.12.2021; MDPI
• Subjects: 16S rRNA gene; Antibiotics; Bacteria; Bacterial infections; Cardinium; Chalcidoidea; Endosymbionts; Eulophidae; Gene sequencing; Genomes; High temperature; Hymenoptera; Laboratories; Males; Microsporidia; Offspring; Ovaries; Parasitoids; Parthenogenesis; PCR detection; Rare species; Reproduction; Reproduction (biology); reproductive mode; Rickettsia; rRNA 16S; Wolbachia; Beijing China; China; PCR detection; Chalcidoidea; endosymbionts; reproductive mode; 16S rRNA gene
• ISSN: 2075-4450; 2075-4450
• DOI: 10.3390/insects13010009

In Hymenoptera parasitoids, the reproductive mode is arrhenotoky, while a few species reproduce by thelytoky. The thelytoky of Hymenoptera parasitoids is generally genetically determined by the parasitoids themselves or induced by bacteria, including , , and . (Hymenoptera: Eulophidae), a recently reported thelytokous species is a main parasitoid attacking agromyzid leafminers. To assess whether endosymbionts induce thelytoky in , we performed universal PCR detection and sequenced the V3-V4 region of 16S ribosomal RNA gene. In addition, bacteria were removed through high-temperature and antibiotic treatments, and the localized bacteria were detected using FISH. Based on general PCR detection, , , , , , and Microsporidia were absent in laboratory and field individuals of thelytokous . Furthermore, 16S rRNA gene sequencing revealed that the dominant endosymbionts in thelytokous were not reproductive manipulators. High-temperature and antibiotic treatment for five consecutive generations cannot reverse the thelytokous pattern of , and no male offspring were produced. Moreover, no bacterial spots were found in the ovaries of . Thus, it is considered that the thelytoky of . does not result in the presence of endosymbionts. This species is thus the second reported eulophid parasitoid whose thelytoky appears not to be associated with endosymbionts.