Dynamics of the genetic structure of the Krasnodar greenbug population under host plant alteration

AbstractHost plant associated genetic differentiation is a common phenomenon in phytophagous insects, but the degree to which such associations sequentially drive diversification at higher trophic levels is not as well understood. A recent study examining neutral molecular markers inHyalopterusaphids revealed that genetic structure in this genus is strongly determined by primary host plant use (Prunusspp.). In this paper, we take a similar approach to determine whether this host plant specificity has affected genetic structure in the parasitoidAphidius transcaspicus, an important natural enemy ofHyalopterusspp. in the Mediterranean. Mitochondrial DNA (428 bp) and seven microsatellite loci were examined in parasitoids collected from aphid populations on almond, apricot, peach and plum trees from Spain and Greece. In contrast to the previous findings forHyalopterusfrom the same regions, here we find no evidence for host associated diversification inA. transcaspicusat the species level or below, though geographic structure between regional populations is exceptionally high. These findings have several implications for our understanding of the ecology and evolution ofA. transcaspicusas well as for its use as a biological control agent forHyalopterus, suggesting that a consideration of host plant specificity may be less critical than factors such as climatic suitability or geographic origins of invasive populations.

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The Genetic Structure of Host Plant Adaptation in a Spatial Patchwork: Demographic Variability among Reciprocally Transplanted Pea Aphid Clones

Evolution ◽

10.2307/2409692 ◽

1991 ◽

Vol 45 (4) ◽

pp. 827 ◽

Cited By ~ 129

Author(s):

Sara Via

Keyword(s):

Genetic Structure ◽

Host Plant ◽

Pea Aphid ◽

Plant Adaptation ◽

Host Plant Adaptation ◽

Aphid Clones

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Genetic Divergence of Two Sitobion avenae Biotypes on Barley and Wheat in China

Insects ◽

10.3390/insects11020117 ◽

2020 ◽

Vol 11 (2) ◽

pp. 117

Author(s):

Da Wang ◽

Xiaoqin Shi ◽

Deguang Liu ◽

Yujing Yang ◽

Zheming Shang

Keyword(s):

Genetic Diversity ◽

Genetic Structure ◽

Genetic Differentiation ◽

Host Plant ◽

Genetic Divergence ◽

Isolation By Distance ◽

Critical Role ◽

Geographic Distance ◽

Sitobion Avenae ◽

Insect Populations

Host plant affinity and geographic distance can play critical roles in the genetic divergence of insect herbivores and evolution of insect biotypes, but their relative importance in the divergence of insect populations is still poorly understood. We used microsatellite markers to test the effects of host plant species and geographic distance on divergence of two biotypes of the English grain aphid, Sitobion avenae (Fabricius). We found that clones of S. avenae from western provinces (i.e., Xinjiang, Gansu, Qinghai and Shaanxi) had significantly higher genetic diversity than those from eastern provinces (i.e., Anhui, Henan, Hubei, Zhejiang and Jiangsu), suggesting their differentiation between both areas. Based on genetic diversity and distance estimates, biotype 1 clones of eastern provinces showed high genetic divergence from those of western provinces in many cases. Western clones of S. avenae also showed higher genetic divergence among themselves than eastern clones. The Mantel test identified a significant isolation-by-distance (IBD) effect among different geographic populations of S. avenae, providing additional evidence for a critical role of geography in the genetic structure of both S. avenae biotypes. Genetic differentiation (i.e., FST) between the two biotypes was low in all provinces except Shaanxi. Surprisingly, in our analyses of molecular variance, non-significant genetic differentiation between both biotypes or between barley and wheat clones of S. avenae was identified, showing little contribution of host-plant associated differentiation to the divergence of both biotypes in this aphid. Thus, it is highly likely that the divergence of the two S. avenae biotypes involved more geographic isolation and selection of some form than host plant affinity. Our study can provide insights into understanding of genetic structure of insect populations and the divergence of insect biotypes.

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Inconsistent genetic structure among members of a multitrophic system: did bruchid parasitoids (Horismenusspp.) escape the effects of bean domestication?

Bulletin of Entomological Research ◽

10.1017/s000748531200051x ◽

2012 ◽

Vol 103 (2) ◽

pp. 182-192 ◽

Cited By ~ 8

Author(s):

S. Laurin-Lemay ◽

B. Angers ◽

B. Benrey ◽

J. Brodeur

Keyword(s):

Genetic Structure ◽

Host Plant ◽

Evolutionary History ◽

Evolutionary Dynamics ◽

Trophic Levels ◽

Plant Domestication ◽

Parasitoid Species ◽

Genetic Structuring ◽

Ancestral Gene ◽

History Of

AbstractAnthropogenic range expansion and cultural practices have modified the distribution, abundance and genetic diversity of domesticated organisms, thereby altering multitrophic assemblages through space and time. The putative Mesoamerican domestication centre of the common bean,Phaseolus vulgarisL., in Mexico allows investigating the effects of plant domestication on the genetic structure of members of a multitrophic system. The aim of this study was to compare the evolutionary history ofHorismenusparasitoids (Hymenoptera: Eulophidae) to those of their bruchid beetle hosts (Coleoptera: Bruchidae) and their domesticated host plant (P. vulgaris), in the context of traditional agriculture in Mexico. We analyzed the population genetic structure of fourHorismenusspecies in Mexico using mitochondrialCOIhaplotype data. The two most abundant parasitoid species wereHorismenus depressusandHorismenus missouriensis. Horismenus missouriensiswere infected byWolbachiaendosymbionts and had little to no population differentiation (FST = 0.06). We suspect the mitochondrial history ofH. missouriensisto be blurred byWolbachia, because differentiation among infected vs. non-infected individuals exists (FST = 0.11). Populations ofH. depressuswere found to be highly differentiated (FST = 0.34), but the genetic structuring could not be explained by tested spatial components. We then compared the genetic structure observed in this parasitoid species to previously published studies on bruchid beetles and their host plants. Despite extensive human-mediated migration and likely population homogenization of its twoAcanthoscelidesbruchid beetle hosts,H. depressuspopulations are structured like its host plant, by a recent dispersal from a diverse ancestral gene pool. Distinct evolutionary dynamics may explain inconsistent patterns among trophic levels. Parasitoids likely migrate from wild bean populations and are poorly adapted to bean storage conditions similar to their bruchid beetle hosts. Integrating several trophic levels to the study of evolutionary history has proven to be fruitful in detecting different ecological responses to human-mediated disturbances and host parasite interactions.

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