Widespread plant specialization in the polyphagous planthopper Hyalesthes obsoletus (Cixiidae), a major vector of stolbur phytoplasma: Evidence of cryptic speciation

2018
Authors
Kosovac, Andrea
Johannesen, Jes
Krstić, Oliver

Mitrović, Milana

Cvrković, Tatjana

Toševski, Ivo

Jović, Jelena

Article (Published version)
Metadata
Show full item recordAbstract
The stolbur phytoplasma vector Hyalesthes obsoletus is generally considered as a polyphagous species associated with numerous wild and cultivated plants. However, recent research in southeastern Europe, the distribution centre of H. obsoletus and the area of most stolbur-inflicted crop diseases, points toward specific host-plant associations of the vector, indicating specific vector-based transmission routes. Here, we study the specificity of populations associated with four host-plants using mitochondrial and nuclear genetic markers, and we evaluate the evolution of host-shifts in H. obsoletus. Host-plant use was confirmed for Convolvulus arvensis, Urtica dioica, Vitex agnus-castus and Crepis foetida. Mitochondrial genetic analysis showed sympatric occurrence of three phylogenetic lineages that were ecologically delineated by host-plant preference, but were morphologically inseparable. Nuclear data supported the existence of three genetic groups (Evanno's Delta K(3) = 803.72) with ave...rage genetic membership probabilities gt 90%. While populations associated with C. arvensis and U. dioica form a homogenous group, populations affiliated with V. agnus-castus and C. foetida constitute two independent plant-associated lineages. The geographical signal permeating the surveyed populations indicated complex diversification processes associated with host-plant selection and likely derived from post-glacial refugia in the eastern Mediterranean. This study provides evidence for cryptic species diversification within H. obsoletus sensu lato: i) consistent mitochondrial differentiation (1.1-1.5%) among host-associated populations in syntopy and in geographically distant areas, ii) nuclear genetic variance supporting mitochondrial data, and iii) average mitochondrial genetic distances among host-associated meta-populations are comparable to the most closely related, morphologically distinguishable species, i.e., Hyalesthes thracicus (2.1-3.3%).
Source:
PlOS One, 2018, 13, 5Publisher:
- Public Library of Science (PLoS)
Projects:
- Agrobiodiversity and land-use change in Serbia: an integrated biodiversity assessment of key functional groups of arthropods and plant pathogens (RS-43001)
- Stiftung Rheinland-Pfalz fur Innovation - 15202-386261/861
- SCOPES program of the Swiss National Science Foundation - IZ73Z0_152414
DOI: 10.1371/journal.pone.0196969
ISSN: 1932-6203
PubMed: 29738577