Molecular Characterization of the Vairimorpha (Nosema) ceranae Infection from Bombus terrestris (Linnaeus, 1758) (Hymenoptera: Apidae) in Turkey

The current study aimed to determine the natural Microsporidium pathogen of the Bombus terrestris L. (Hymenoptera: Apidae) in Turkey (Mersin, Antalya, Mugla, Izmir, Aydin). During 2019 and 2020, the commercial and wild populations of B. terrestris were investigated in this survey. In the studies, natural microsporidiosis was detected in commercial B. terrestris populations. Fresh oval spores were measured as 4.91 +/- 0.48 (6.12 - 3.73) mu m in length and 2.54 +/- 0.31 (3.27 - 1.88) mu m in width (n=60). Both SSU rRNA and RPB1 gene sequences of the current microsporidium were top hits with the Vairimorpha (Nosema) ceranae isolates. While the SSU rRNA gene sequence matched with the Vairimorpha ceranae clone NCS44 (LC510228) isolated from the Apis cerana japonica at 99.24% identity (100% coverage), the RPB1 gene sequence was matched with the Vairimorpha ceranae isolate 1994 (KJ473287) at 99.02% identity (100% coverage). Based on the light microscopy and molecular phylogeny the current microsporidium was a new isolate of the V ceranae and named here in as Vairimorpha ceranae Tr-07.

Automated summary

The study in Turkey identified a new pathogen, Vairimorpha ceranae Tr-07, causing natural microsporidiosis in commercial Bombus terrestris populations, with spore morphology and gene sequences closely matching those of Vairimorpha ceranae.