Comparison of bacterial diversity and abundance between sexes of Leptocybe invasa Fisher & La Salle (Hymenoptera: Eulophidae) from China

Abstract

Background Insects harbor a myriad of microorganisms, many of which can affect the sex ratio and manipulate the reproduction of the host. Leptocybe invasa is an invasive pest that causes serious damage to eucalyptus plantations, and the thelytokous parthenogenesis, low temperature resistance, protection in galls, generation overlap and small body of L. invasa contribute to its rapid invasion and population growth. However, the endosymbiotic bacterial composition, abundance and sex differences of L. invasa remain unclear. Therefore, this research aimed to identify the bacterial communities in L. invasa adults and compare them between the sexes of L. invasa lineage B. Results The Illumina MiSeq platform was used to compare bacterial community composition between females and males of L. invasa by sequencing the V3–V4 region of the 16S ribosomal RNA gene. A total of 1,320 operational taxonomic units (OTUs) were obtained. These OTUs were subdivided into 24 phyla, 71 classes, 130 orders, 245 families and 501 genera. At the genus level, the dominant bacteria in females and males were Rickettsia and Rhizobium, respectively. Conclusion The endosymbiotic bacteria of L. invasa females and males were highly diverse. There were differences in the bacterial community of L. invasa between sexes, and the bacterial diversity in male specimens was greater than that in female specimens. This study presents a comprehensive comparison of bacterial communities in L. invasa and these data will provide an overall view of the bacterial community in both sexes of L. invasa with special attention on sex-related bacteria.

Influential Insider: Wolbachia, an Intracellular Symbiont, Manipulates Bacterial Diversity in Its Insect Host

“…The Bacteroidia Flavobacterium helps digesting plant material by producing cellulase in three phytophagous insect species [ 52 ] while Sphingobacterium induces resistance against fungal infection in Delia antiqua larvae [ 66 ]. Although the α-proteobacterial ANPR or Rhizobium is usually known as a nitrogen-fixing bacterium living in symbiosis with legume roots [ 67 ], it has also been detected in insects [ 68 ], where a gene associated to nitrogen fixation was revealed in ants that host Rhizobiales [ 69 ]. The γ-proteobacterial Acinetobacter improves both its host nutrition and defense by scavenging nitrogen [ 70 ], producing cellulase [ 52 ], and resisting and degrading plant defenses, respectively in D. radicum [ 53 ] and in the gypsy moth [ 71 ].…”

Host species identity shapes the diversity and structure of insect microbiota

“…While sex is often not considered when studying insect microbial communities, there is evidence of differences in microbiota composition between females and males in Leptocybe invasa (Guo et al, 2020), Dendroctonus valens (Xu et al, 2016), Anopheles gambiae and Anopheles coluzzii (Segata et al, 2016).…”

Bacterial diversity of Leptocybe invasa Fisher & La Salle (Hymenoptera: Eulophidae) from different geographical conditions in China

“…Previous studies confirmed that females pass Rickettsia to the next generation using vertical transmission (Brumin et al, 2012;Giorgini et al, 2010). Himler et al (2011) showed that the rate of Rickettsia to offspring was close to 100% by female vertical transmission, and the same phenomenon may also be reflected in L. invasa (Guo et al, 2020;Nugnes et al, 2015). Remarkably, some studies have demonstrated the presence of horizontal transmission of Rickettsia, although transmission was mainly achieved by mating or feeding on the same host plants (Brumin et al, 2012;Caspi-Fluger et al, 2012).…”

“…Rickettsia (Guo et al, 2020), while no available evidence could prove the phenomenon of horizontal transmission in L. invasa (Gualtieri et al, 2017) which will be our study of the next stage.…”