1
|
Black EN, Blair JD, van der Burg KRL, Marshall KE. Crowd-sourced observations of a polyphagous moth reveal evidence of allochronic speciation varying along a latitudinal gradient. PLoS One 2023; 18:e0288415. [PMID: 37440520 DOI: 10.1371/journal.pone.0288415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 06/26/2023] [Indexed: 07/15/2023] Open
Abstract
Allochronic speciation, where reproductive isolation between populations of a species is facilitated by a difference in reproductive timing, depends on abiotic factors such as seasonality and biotic factors such as diapause intensity. These factors are strongly influenced by latitudinal trends in climate, so we hypothesized that there is a relationship between latitude and divergence among populations separated by life history timing. Hyphantria cunea (the fall webworm), a lepidopteran defoliator with red and black colour morphs, is hypothesized to be experiencing an incipient allochronic speciation. However, given their broad geographic range, the strength of allochronic speciation may vary across latitude. We annotated >11,000 crowd-sourced observations of fall webworm to model geographic distribution, phenology, and differences in colour phenotype between morphs across North America. We found that red and black morph life history timing differs across North America, and the phenology of morphs diverges more in warmer climates at lower latitudes. We also found some evidence that the colour phenotype of morphs also diverges at lower latitudes, suggesting reduced gene flow between colour morphs. Our results demonstrate that seasonality in lower latitudes may increase the strength of allochronic speciation in insects, and that the strength of sympatric speciation can vary along a latitudinal gradient. This has implications for our understanding of broad-scale speciation events and trends in global biodiversity.
Collapse
Affiliation(s)
- Emily N Black
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jarrett D Blair
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Karin R L van der Burg
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Katie E Marshall
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| |
Collapse
|
2
|
Genomic and ecological evidence shed light on the recent demographic history of two related invasive insects. Sci Rep 2022; 12:19629. [PMID: 36385480 PMCID: PMC9669014 DOI: 10.1038/s41598-022-21548-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 09/28/2022] [Indexed: 11/17/2022] Open
Abstract
Hypogeococcus pungens is a species complex native to southern South America that is composed of at least five putative species, each one specialized in the use of different host plants. Two of these undescribed species were registered as invasive in Central and North America: Hyp-C is a cactophagous mealybug that became an important pest that threatens endemic cactus species in Puerto Rico, and Hyp-AP feeds on Amaranthaceae and Portulacaceae hosts, but does not produce severe damage to the host plants. We quantified genomic variation and investigated the demographic history of both invasive species by means of coalescent-based simulations using high throughput sequencing data. We also evaluated the incidence of host plant infestation produced by both species and used an ecological niche modeling approach to assess potential distribution under current and future climatic scenarios. Our genetic survey evinced the footprints of strong effective population size reduction and signals of genetic differentiation among populations within each species. Incidence of plant attacks varied between species and among populations within species, with some host plant species preferred over others. Ecological niche modeling suggested that under future climatic scenarios both species would expand their distribution ranges in Puerto Rico. These results provide valuable information for the design of efficient management and control strategies of the Puerto Rican cactus pest and shed light on the evolutionary pathways of biological invasions.
Collapse
|
3
|
Bessette M, Ste‐Croix DT, Brodeur J, Mimee B, Gagnon A. Population genetic structure of the carrot weevil (
Listronotus oregonensis
) in North America. Evol Appl 2022; 15:300-315. [PMID: 35233249 PMCID: PMC8867704 DOI: 10.1111/eva.13343] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 12/30/2021] [Indexed: 11/29/2022] Open
Abstract
Population genetic studies of insect pests enhance our ability to anticipate problems in agroecosystems, such as pest outbreaks, insecticide resistance, or expansions of the host range. This study focuses on geographic distance and host plant selection as potential determinants of genetic differentiation of the carrot weevil Listronotus oregonensis, a major pest of several apiaceous crops in North America. To undertake genetic studies on this species, we assembled the first complete genome sequence for L. oregonensis. Then, we used both haplotype discrimination with mitochondrial DNA (mtDNA) and a genotyping‐by‐sequencing (GBS) approach to characterize the genetic population structure. A total of 220 individuals were sampled from 17 localities in the provinces of Québec, Ontario, Nova Scotia (Canada), and the state of Ohio (USA). Our results showed significant genetic differences between distant populations across North America, indicating that geographic distance represents an important factor of differentiation for the carrot weevil. Furthermore, the GBS analysis revealed more different clusters than COI analysis between Québec and Nova Scotia populations, suggesting a recent differentiation in the latter province. In contrast, we found no clear evidence of population structure associated with the four cultivated apiaceous plants tested (carrot, parsley, celery, and celeriac) using populations from Québec. This first characterization of the genetic structure of the carrot weevil contributes to a better understanding of the gene flow of the species and helps to adapt local pest management measures to better control this agricultural pest.
Collapse
Affiliation(s)
- Marianne Bessette
- Saint‐Jean‐sur‐Richelieu Research and Development Centre, Agriculture and Agri‐Food Canada
- Institut de recherche en biologie végétale, Département de sciences biologiques, Université de Montréal
| | - Dave T. Ste‐Croix
- Saint‐Jean‐sur‐Richelieu Research and Development Centre, Agriculture and Agri‐Food Canada
| | - Jacques Brodeur
- Institut de recherche en biologie végétale, Département de sciences biologiques, Université de Montréal
| | - Benjamin Mimee
- Saint‐Jean‐sur‐Richelieu Research and Development Centre, Agriculture and Agri‐Food Canada
| | - Annie‐Ève Gagnon
- Saint‐Jean‐sur‐Richelieu Research and Development Centre, Agriculture and Agri‐Food Canada
| |
Collapse
|
4
|
Sunde J, Yıldırım Y, Tibblin P, Bekkevold D, Skov C, Nordahl O, Larsson P, Forsman A. Drivers of neutral and adaptive differentiation in pike (Esox lucius) populations from contrasting environments. Mol Ecol 2021; 31:1093-1110. [PMID: 34874594 DOI: 10.1111/mec.16315] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 11/29/2021] [Accepted: 12/01/2021] [Indexed: 01/28/2023]
Abstract
Understanding how eco-evolutionary processes and environmental factors drive population differentiation and adaptation are key challenges in evolutionary biology of relevance for biodiversity protection. Differentiation requires at least partial reproductive separation, which may result from different modes of isolation such as geographic isolation (allopatry) or isolation by distance (IBD), resistance (IBR), and environment (IBE). Despite that multiple modes might jointly influence differentiation, studies that compare the relative contributions are scarce. Using RADseq, we analyse neutral and adaptive genetic diversity and structure in 11 pike (Esox lucius) populations from contrasting environments along a latitudinal gradient (54.9-63.6°N), to investigate the relative effects of IBD, IBE and IBR, and to assess whether the effects differ between neutral and adaptive variation, or across structural levels. Patterns of neutral and adaptive variation differed, probably reflecting that they have been differently affected by stochastic and deterministic processes. The importance of the different modes of isolation differed between neutral and adaptive diversity, yet were consistent across structural levels. Neutral variation was influenced by interactions among all three modes of isolation, with IBR (seascape features) playing a central role, wheares adaptive variation was mainly influenced by IBE (environmental conditions). Taken together, this and previous studies suggest that it is common that multiple modes of isolation interactively shape patterns of genetic variation, and that their relative contributions differ among systems. To enable identification of general patterns and understand how various factors influence the relative contributions, it is important that several modes are simultaneously investigated in additional populations, species and environmental settings.
Collapse
Affiliation(s)
- Johanna Sunde
- Ecology and Evolution in Microbial Model Systems, EEMiS, Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden
| | - Yeşerin Yıldırım
- Ecology and Evolution in Microbial Model Systems, EEMiS, Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden
| | - Petter Tibblin
- Ecology and Evolution in Microbial Model Systems, EEMiS, Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden
| | - Dorte Bekkevold
- National Institute of Aquatic Resources, Technical University of Denmark, Silkeborg, Denmark
| | - Christian Skov
- National Institute of Aquatic Resources, Technical University of Denmark, Silkeborg, Denmark
| | - Oscar Nordahl
- Ecology and Evolution in Microbial Model Systems, EEMiS, Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden
| | - Per Larsson
- Ecology and Evolution in Microbial Model Systems, EEMiS, Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden
| | - Anders Forsman
- Ecology and Evolution in Microbial Model Systems, EEMiS, Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden
| |
Collapse
|
5
|
Poveda-Martínez D, Varone L, Fuentes Corona M, Hight S, Logarzo G, Hasson E. Spatial and host related genomic variation in partially sympatric cactophagous moth species. Mol Ecol 2021; 31:356-371. [PMID: 34662480 DOI: 10.1111/mec.16232] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 10/06/2021] [Accepted: 10/11/2021] [Indexed: 01/17/2023]
Abstract
Surveys of patterns of genetic variation in natural sympatric and allopatric populations of recently diverged species are necessary to understand the processes driving intra- and interspecific diversification. The South American moths Cactoblastis cactorum, Cactoblastis doddi and Cactoblastis bucyrus are specialized in the use of cacti as host plants. These species have partially different geographic ranges and differ in patterns of host plant use. However, there are areas that overlap, particularly, in northwestern Argentina, where they are sympatric. Using a combination of genome-wide SNPs and mitochondrial data we assessed intra and interspecific genetic variation and investigated the relative roles of geography and host plants on genetic divergence. We also searched for genetic footprints of hybridization between species. We identified three well delimited species and detected signs of hybridization in the area of sympatry. Our results supported a hypothetical scenario of allopatric speciation in the generalist C. cactorum and genetic interchange during secondary geographic contact with the pair of specialists C. bucyrus and C. doddi that probably speciated sympatrically. In both cases, adaptation to new host plants probably played an important role in speciation. The results also suggested the interplay of geography and host plant use as drivers of divergence and limiting gene flow at intra and interspecific levels.
Collapse
Affiliation(s)
- Daniel Poveda-Martínez
- Fundación para el Estudio de Especies Invasivas (FuEDEI), Hurlingham, Buenos Aires, Argentina.,Instituto de Ecología Genética y Evolución de Buenos Aires (IEGEBA), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.,Grupo de investigación en Evolución, Ecología y Conservación (EECO), Universidad del Quindío, Armenia, Colombia.,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Laura Varone
- Fundación para el Estudio de Especies Invasivas (FuEDEI), Hurlingham, Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Malena Fuentes Corona
- Fundación para el Estudio de Especies Invasivas (FuEDEI), Hurlingham, Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Stephen Hight
- Insect Behavior and Biocontrol Research Unit (IBBRU), USDA-ARS, Tallahassee, Florida, USA
| | - Guillermo Logarzo
- Fundación para el Estudio de Especies Invasivas (FuEDEI), Hurlingham, Buenos Aires, Argentina
| | - Esteban Hasson
- Instituto de Ecología Genética y Evolución de Buenos Aires (IEGEBA), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| |
Collapse
|
6
|
Peterson DA, Hardy NB, Morse GE, Itioka T, Wei J, Normark BB. Nonadaptive host-use specificity in tropical armored scale insects. Ecol Evol 2020; 10:12910-12919. [PMID: 33304503 PMCID: PMC7713922 DOI: 10.1002/ece3.6867] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 08/14/2020] [Accepted: 09/08/2020] [Indexed: 01/05/2023] Open
Abstract
Most herbivorous insects are diet specialists in spite of the apparent advantages of being a generalist. This conundrum might be explained by fitness trade-offs on alternative host plants, yet the evidence of such trade-offs has been elusive. Another hypothesis is that specialization is nonadaptive, evolving through neutral population-genetic processes and within the bounds of historical constraints. Here, we report on a striking lack of evidence for the adaptiveness of specificity in tropical canopy communities of armored scale insects. We find evidence of pervasive diet specialization, and find that host use is phylogenetically conservative, but also find that more-specialized species occur on fewer of their potential hosts than do less-specialized species, and are no more abundant where they do occur. Of course local communities might not reflect regional diversity patterns. But based on our samples, comprising hundreds of species of hosts and armored scale insects at two widely separated sites, more-specialized species do not appear to outperform more generalist species.
Collapse
Affiliation(s)
- Daniel A. Peterson
- Department of Biology and Graduate Program in Organismic and Evolutionary BiologyUniversity of MassachusettsAmherstMAUSA
| | - Nate B. Hardy
- Department of Entomology and Plant PathologyAuburn UniversityAuburnALUSA
| | | | - Takao Itioka
- Graduate School of Human and Environmental StudiesKyoto UniversityKyotoJapan
| | - Jiufeng Wei
- College of AgricultureShanxi Agricultural UniversityTaiguChina
| | - Benjamin B. Normark
- Department of Biology and Graduate Program in Organismic and Evolutionary BiologyUniversity of MassachusettsAmherstMAUSA
| |
Collapse
|
7
|
Brookes DR, Hereward JP, Wilson LJ, Walter GH. Multiple invasions of a generalist herbivore-Secondary contact between two divergent lineages of Nezara viridula Linnaeus in Australia. Evol Appl 2020; 13:2113-2129. [PMID: 32908608 PMCID: PMC7463329 DOI: 10.1111/eva.12971] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 03/18/2020] [Accepted: 03/21/2020] [Indexed: 11/28/2022] Open
Abstract
The presence of distinct evolutionary lineages within herbivorous pest insect taxa requires close attention. Scientific understanding, biosecurity planning and practice, and pest management decision-making each suffer when such situations remain poorly understood. The pest bug Nezara viridula Linnaeus has been recorded from numerous host plants and has two globally distributed mitochondrial (mtDNA) lineages. These mtDNA lineages co-occur in few locations globally, and the consequences of their divergence and recent secondary contact have not been assessed. We present evidence that both mtDNA lineages of N. viridula are present in Australia and their haplotype groups have a mostly separate distribution from one another. The north-western population has only Asian mtDNA haplotypes, and the population with an eastern distribution is characterized mostly by European mtDNA haplotypes. Haplotypes of both lineages were detected together at only one site in the north of eastern Australia, and microsatellite data indicate that this secondary contact has resulted in mating across the lineages. Admixture and the movement of mtDNA haplotypes outside of this limited area of overlap has not, however, been extensive. Some degree of mating incompatibility or differences in the climatic requirements and tolerances of the two lineages, and perhaps a combination of these influences, might limit introgression and the movement of individuals, but this needs to be tested. This work provides the foundation for further ecological investigation of the lineages of N. viridula, particularly the consequences of admixture on the ecology of this widespread pest. We propose that for now, the Asian and European lineages of N. viridula would best be investigated as subspecies, so that "pure" and admixed populations of this bug can each be considered directly with respect to management and research priorities.
Collapse
Affiliation(s)
- Dean Robert Brookes
- School of Biological SciencesThe University of QueenslandBrisbaneQLDAustralia
| | - James P. Hereward
- School of Biological SciencesThe University of QueenslandBrisbaneQLDAustralia
| | - Lewis J. Wilson
- Cotton Research UnitCSIRO Agriculture and FoodNarrabriNSWAustralia
| | - Gimme Hugh Walter
- School of Biological SciencesThe University of QueenslandBrisbaneQLDAustralia
| |
Collapse
|
8
|
Cheng J, Kao H, Dong S. Population genetic structure and gene flow of rare and endangered Tetraena mongolica Maxim. revealed by reduced representation sequencing. BMC PLANT BIOLOGY 2020; 20:391. [PMID: 32842966 PMCID: PMC7448513 DOI: 10.1186/s12870-020-02594-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 08/12/2020] [Indexed: 05/28/2023]
Abstract
BACKGROUND Studying population genetic structure and gene flow of plant populations and their influencing factors is of particular significance in the field of conservation biology, especially important for species such as rare and endangered plants. Tetraena mongolica Maxim. (TM), belongs to Zygophyllaceae family, a rare and endangered plant with narrow distribution. However, for the last decade, due to excessive logging, urban expansion, industrial and tourism development, habitat fragmentation and loss of natural habitats have become major threats to the population of endangered plants. RESULTS In this study, genetic diversity, population genetic structure and gene flow of TM populations were evaluated by reduced representation sequencing technology, and a total of more than 133.45 GB high-quality clean reads and 38,097 high-quality SNPs were generated. Analysis based on multiple methods, we found that the existing TM populations have moderate levels of genetic diversity, and very low genetic differentiation as well as high levels of gene flow between populations. Population structure and principal coordinates analysis showed that 8 TM populations can be divided into two groups. The Mantel test detected no significant correlation between geographical distances and genetic distance for the whole sampling. Moreover, the migration model indicated that the gene flow is more of a north to south migration pattern in history. CONCLUSIONS This study demonstrates that the present genetic structure is mainly due to habitat fragmentation caused by urban sprawl, industrial development and coal mining. Our recommendation with respect to conservation management is that, all 8 populations should be preserved as a whole population, rather than just those in the core area of TM nature reserve. In particular, the populations near the edge of TM distribution in cities and industrial areas deserve our special protection.
Collapse
Affiliation(s)
- Jin Cheng
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Huixia Kao
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China
| | - Shubin Dong
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, China.
| |
Collapse
|
9
|
Poveda-Martínez D, Aguirre MB, Logarzo G, Hight SD, Triapitsyn S, Diaz-Sotero H, Diniz Vitorino M, Hasson E. Species complex diversification by host plant use in an herbivorous insect: The source of Puerto Rican cactus mealybug pest and implications for biological control. Ecol Evol 2020; 10:10463-10480. [PMID: 33072273 PMCID: PMC7548167 DOI: 10.1002/ece3.6702] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 07/28/2020] [Accepted: 07/29/2020] [Indexed: 01/06/2023] Open
Abstract
Cryptic taxa have often been observed in the form of host‐associated species that diverged as the result of adaptation to alternate host plants. Untangling cryptic diversity in species complexes that encompass invasive species is a mandatory task for pest management. Moreover, investigating the evolutionary history of a species complex may help to understand the drivers of their diversification. The mealybug Hypogeococcus pungens was believed to be a polyphagous species from South America and has been reported as a pest devastating native cacti in Puerto Rico, also threatening cactus diversity in the Caribbean and North America. There is neither certainty about the identity of the pest nor the source population from South America. Recent studies pointed to substantial genetic differentiation among local populations, suggesting that H. pungens is a species complex. In this study, we used a combination of genome‐wide SNPs and mtDNA variation to investigate species diversity within H. pungens sensu lato to establish host plant ranges of each one of the putative members of the complex, to evaluate whether the pattern of host plant association drove diversification in the species complex, and to determine the source population of the Puerto Rican cactus pest. Our results suggested that H. pungens comprises at least five different species, each one strongly associated with specific host plants. We also established that the Puerto Rican cactus pest derives from southeastern Brazilian mealybugs. This is an important achievement because it will help to design reliable strategies for biological control using natural enemies of the pest from its native range.
Collapse
Affiliation(s)
- Daniel Poveda-Martínez
- Fundación para el Estudio de Especies Invasivas (FuEDEI) Hurlingham Argentina.,Instituto de Ecología Genética y Evolución de Buenos Aires (IEGEBA) Departamento de Ecología Genética y Evolución Universidad de Buenos Aires Buenos Aires Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Ciudad Autónoma de Buenos Aires Argentina.,Grupo de investigación en Evolución, Ecología y Conservación (EECO) Universidad del Quindío Armenia Colombia
| | - María Belén Aguirre
- Fundación para el Estudio de Especies Invasivas (FuEDEI) Hurlingham Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Ciudad Autónoma de Buenos Aires Argentina
| | - Guillermo Logarzo
- Fundación para el Estudio de Especies Invasivas (FuEDEI) Hurlingham Argentina
| | | | | | - Hilda Diaz-Sotero
- Caribbean Advisor to the APHIS Administrator USDA San Juan Puerto Rico
| | - Marcelo Diniz Vitorino
- Departamento de Engenharia Florestal Programa de Pós-graduação em Engenharia Florestal - PPGEF Lab. de Monitoramento e Proteção Florestal - LAMPF Universidade Regional de Blumenau - FURB Blumenau Brazil
| | - Esteban Hasson
- Instituto de Ecología Genética y Evolución de Buenos Aires (IEGEBA) Departamento de Ecología Genética y Evolución Universidad de Buenos Aires Buenos Aires Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Ciudad Autónoma de Buenos Aires Argentina
| |
Collapse
|
10
|
Wang D, Shi X, Liu D, Yang Y, Shang Z. Genetic Divergence of Two Sitobion avenae Biotypes on Barley and Wheat in China. INSECTS 2020; 11:insects11020117. [PMID: 32054103 PMCID: PMC7073604 DOI: 10.3390/insects11020117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 02/07/2020] [Accepted: 02/07/2020] [Indexed: 11/16/2022]
Abstract
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.
Collapse
Affiliation(s)
- Da Wang
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling 712100, Shaanxi, China; (D.W.); (Y.Y.); (Z.S.)
- College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Xiaoqin Shi
- Department of Foreign Languages, Northwest A&F University, Yangling 712100, Shaanxi, China;
| | - Deguang Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling 712100, Shaanxi, China; (D.W.); (Y.Y.); (Z.S.)
- College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China
- Correspondence:
| | - Yujing Yang
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling 712100, Shaanxi, China; (D.W.); (Y.Y.); (Z.S.)
- College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Zheming Shang
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling 712100, Shaanxi, China; (D.W.); (Y.Y.); (Z.S.)
- College of Plant Protection, Northwest A&F University, Yangling 712100, Shaanxi, China
| |
Collapse
|