Population structure, adaptation and divergence of the meadow spittlebug, Philaenus spumarius (Hemiptera, Aphrophoridae), revealed by genomic and morphological data

PeerJ

article

Sofia G. Seabra¹  Ana S.B. Rodrigues¹  Sara E. Silva¹  Ana Carina Neto²  Francisco Pina-Martins¹  Eduardo Marabuto¹  Vinton Thompson³  Michael R. Wilson⁴  Selçuk Yurtsever⁵  Antti Halkka⁶  Maria Teresa Rebelo²  Paulo A.V. Borges⁷  José A. Quartau¹  Chris D. Jiggins⁸  Octávio S. Paulo¹ 

[1] E3c - Centre for Ecology, Evolution and Environmental Changes, Departamento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa;CESAM - Centre for Environmental and Marine Studies, Departamento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa;American Museum of Natural History;National Museum of Wales, Department of Natural Sciences;Trakya University, Biology Department, Science Faculty;Department of Biological and Environmental Sciences, University of Helsinki;cE3c - Centre for Ecology, Evolution and Environmental Changes/Azorean Biodiversity Group, Faculty of Agriculture and Environment, Department of Environmental Sciences and Engineering, Universidade dos Açores;Department of Zoology, University of Cambridge

关键词: Population genomics;    RAD sequencing;    Aedeagus;    Species divergence;    Local adaptation;    Philaenus spumarius;   

DOI  :  10.7717/peerj.11425

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Understanding patterns of population differentiation and gene flow in insect vectors of plant diseases is crucial for the implementation of management programs of disease. We investigated morphological and genome-wide variation across the distribution range of the spittlebug Philaenus spumarius (Linnaeus, 1758) (Hemiptera, Auchenorrhyncha, Aphrophoridae), presently the most important vector of the plant pathogenic bacterium Xylella fastidiosa Wells et al., 1987 in Europe. We found genome-wide divergence between P. spumarius and a very closely related species, P. tesselatus Melichar, 1899, at RAD sequencing markers. The two species may be identified by the morphology of male genitalia but are not differentiated at mitochondrial COI, making DNA barcoding with this gene ineffective. This highlights the importance of using integrative approaches in taxonomy. We detected admixture between P. tesselatus from Morocco and P. spumarius from the Iberian Peninsula, suggesting gene-flow between them. Within P. spumarius, we found a pattern of isolation-by-distance in European populations, likely acting alongside other factors restricting gene flow. Varying levels of co-occurrence of different lineages, showing heterogeneous levels of admixture, suggest other isolation mechanisms. The transatlantic populations of North America and Azores were genetically closer to the British population analyzed here, suggesting an origin from North-Western Europe, as already detected with mitochondrial DNA. Nevertheless, these may have been produced through different colonization events. We detected SNPs with signatures of positive selection associated with environmental variables, especially related to extremes and range variation in temperature and precipitation. The population genomics approach provided new insights into the patterns of divergence, gene flow and adaptation in these spittlebugs and led to several hypotheses that require further local investigation.

【 授权许可】

CC BY