Abstract
Graminivorous sawfly numbers have declined steadily over recent years as a consequence of agricultural intensification. In spite of these declines and the importance of sawflies (Hymenoptera, Symphyta) as a food source for threatened populations of farmland birds, sawfly conservation studies have been restricted to census-based research. This is largely due to certain aspects of the sawfly life-cycle which make adequate sampling of these insects difficult. However, genetic research provides a valuable insight into population structure that cannot be obtained by traditional ecological means, and one which is essential for the development of conservation management strategies. In this study, we investigate the population genetic structure of the graminivorous sawfly Dolerus aeneus, and conduct a preliminary study to determine whether complementary sex determination (CSD), which can produce sterile diploid males under inbreeding conditions, operates in this species. Our research suggests that fragmentation of sawfly habitat as a result of agri-intensification has not yet acted to isolate D. aeneus populations, although some genetic effects are apparent (inbreeding and low diversity compared with other solitary Hymenoptera). In addition, diploid males were detected which may have compromised fertility and could indicate that CSD is operative in D. aeneus. This study highlights the need for further genetic research in sawflies to assess population structure on a UK-wide scale and to assess the prevalence of diploid males in key species. We discuss our findings in wider context of the genetics of Hymenoptera and the conservation and management of farmland biodiversity.
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References
Aebischer NJ (1990) Assessing pesticide effects on non-target invertebrates using long-term monitoring and time series modelling. Funct Ecol 4:369–373
Aebischer NJ (1991) Twenty years of monitoring invertebrates and weeds in cereal fields in Sussex. In: Firbank LG, Carter N, Darbyshire JF, Potts GR (eds) The ecology of temperate cereal fields. Blackwell Scientific Publications, Oxford, pp 305–331
Barker AM, Brown NJ, Reynolds CJM (1999) Do host-plant requirements and mortality from soil cultivation determine the distribution of graminivorous sawflies on farmland? J Appl Ecol 36:271–282
Benson RB (1950) An introduction to the natural history of British sawflies. Transactions of the Society for British Entomology 10:45–142. The Royal Entomological Society, London
Benson RB (1952) Hymenoptera 2. Symphyta. Section (b). Handbooks for the Identification of British Insects 6.2(b):51–137. The Royal Entomological Society, London
Benson RB (1958) Hymenoptera 2 Symphyta Section (c). Handbooks for the Identification of British Insects 6.2(c):139–252. The Royal Entomological Society, London
Chamberlain DE, Fuller RJ, Bunce RGH, Duckworth JC, Shrubb M (2000) Changes in the abundance of farmland birds in relation to the timing of agricultural intensification in England and Wales. J Appl Ecol 37:771–788
Cook JM, Crozier RH (1995) Sex determination and population biology in the Hymenoptera. Trends Ecol Evol 10:281–286
Cook N, Aziz N, Hedley PE, Morris J, Milne L, Karley AJ, Hubbard SF, Russell JR (2011) Transcriptome sequencing of an ecologically important graminivorous sawfly: a resource for marker development. Conserv Genet Resour 3:789–795
Cowan DP, Stahlhut JK (2004) Functionally reproductive diploid and haploid males in an inbreeding hymenopteran with complementary sex determination. Proc Natl Acad Sci USA 101(28):10374–10379
Davis ES, Murray TE, Fitzpatrick U, Brown MJF, Paxton RJ (2010) Landscape effects on extremely fragmented populations of a rare solitary bee, Colletes floralis. Mol Ecol 19:4922–4935
Earl DA, vonHoldt BM (2012) STRUCTURE HARVESTER: a website and program for visualizing STRUCTURE output and implementing the Evanno method. Conserv Genet Resour 4(2):359–361
Elias J, Mazzi D, Dorn S (2009) No need to discriminate? Reproductive diploid males in a parasitoid with complementary sex determination. PLOS One 4(6):e6024
Evanno G, Regnaut S, Goudet J (2005) Detecting the number of clusters of individuals using the software STRUCTURE : a simulation study. Mol Ecol 14:2611–2620
Exeler N, Kratochwil A, Hochkirch A (2010) Does recent habitat fragmentation affect the population genetics of a heathland specialist, Andrena fuscipes (Hymenoptera:Andrenidae)? Conserv Genet 11:1679–1687
Goudet J (2005) Fstat (ver. 2.9.4), a program to estimate and test population genetics parameters. http://www2.unil.ch/popgen/softwares/fstat.htm. Accessed May 2009
Hartel KD, Frederick BA, Shanower TG (2003) Isolation and characterization of microsatellite loci in wheat stem sawfly Cephus cinctus and cross-species amplification in related species. Mol Ecol Notes 3:85–87
Hebert PDN, Cywinska A, Ball SL, deWaard JR (2003) Biological identifications through DNA barcodes. Proc Biol Sci 270:313–321
Heimpel GE, de Boer JG (2008) Sex determination in the Hymenoptera. Annu Rev Entomol 53:209–230
Höglund J (2008) Evolutionary conservation genetics. Oxford University Press, Oxford
Magnacca KN, Brown MJF (2012) DNA barcoding a regional fauna: Irish solitary bees. Mol Ecol Resour 12:990–998
Malaise R (1937) A new insect-trap. Entomol Tidskr Stockholm 58:148–160
Naito T, Suzuki H (1991) Sex determination in the sawfly, Athalia rosae ruficornis (Hymenoptera): occurrence of triploid males. J Hered 82:101–104
Newton I (2004) The recent declines of farmland bird populations in Britain: an appraisal of causal factors and conservation actions. Ibis 146:579–600
Park SDE (2001) Trypanotolerance in West African cattle and the population genetic effects of selection. Ph.D. Thesis, University of Dublin
Peakall R, Smouse PE (2006) GenAlex 6: genetic analysis in excel. Population genetic software for teaching and research. Mol Ecol Notes 6:288–295
Potts GR (1970) Recent changes in the farmland fauna with special reference to the decline of the grey partridge. Bird Study 17:145–166
Potts GR (1986) The Partridge. Pesticides, predation and conservation. Collins, London, UK
Pritchard JK, Stephens M, Donnelly P (2000) Inference of population structure using multilocus genotype Data. Genetics 155:945–959
Randall NP (2002) The Ecology of Graminivorous Sawflies (Hymenoptera:Symphyta) on Lowland Farmland in Scotland. Ph.D. Thesis, University of Dundee
Soro A, Field SJ, Bridge C, Cardinal SC, Paxton RJ (2010) Genetic differentiation across the social transition in a socially polymorphic sweat bee, Halictus rubicundus. Mol Ecol 19:3351–3363
Sotherton NW (1990) The effects of six insecticides used in UK cereal fields on sawfly larvae (Hymenoptera: Tenthredinidae). In: Proceedings of the Brighton Crop Protection Conference, Pests and Diseases 3, 999–1004
Sotherton NW (1998) Land use changes and the decline of farmland wildlife: an appraisal of the set-aside approach. Biol Conserv 83:259–268
Sotherton NW, Aebischer NJ, Ewald JA (2010) The conservation of the grey partridge. In: Maclean N (ed) Silent summer: the state of wildlife in Britain and Ireland. Cambridge University Press, Cambridge, pp 319–336
Souza RO, Del Lama MA, Cervini M, Motari N, Eltz T, Zimmermann Y, Bach C, Brosi BJ, Suni S, Quezada-Euan JJG, Paxton RJ (2009) Conservation genetics of neotropical pollinators revisited: microsatellite analysis suggests that diploid males are rare in orchid bees. Evolution 64(11):3318–3326
Speight MR, Hunter MD, Watt AD (2008) Ecology of insects, concepts and applications. Blackwell Publishing, West Sussex
Spielman D, Brook BW, Frankham R (2004) Most species are not driven to extinction before genetic factors impact them. Proc Natl Acad Sci USA 101:15261–15264
Struebig MJ, Le Comber SC, Rossiter SJ (2012) Overcoming the issue of small sample sizes in fragmentation genetics. Mol Ecol 21:2850–2851
van Oosterhout C, Hutchinson WF, Wills DPM, Shipley P (2004) MICRO-CHECKER: software for identifying and correcting genotyping errors in microsatellite data. Mol Ecol Notes 4:535–538
van Wilgenburg E, Driessen G, Beukeboom LW (2006) Single locus complementary sex determination in Hymenoptera: an “unintelligent” design? Front Zool 3:1. doi:10.1186/1742-9994-3-1
Waterhouse FL (1952) Microclimatic studies on Tenthredinid larvae. Ph.D. Thesis, University of St Andrews
Wright A (1990) (Hymenoptera: Symphyta) A key to adults of the genera occurring in Britain. Preston Montford, Field Studies Council
Zane L, Bargelloni L, Patarnello T (2002) Strategies for microsatellite isolation: a review. Mol Ecol 11:1–16
Zayed A, Packer L (2005) Complementary sex determination substantially increases extinction proneness of haplodiploid populations. Proc Natl Acad Sci USA 102(30):10742–10746
Zhou Y, Gu H, Dorn S (2006) Single-locus sex determination in the parasitoid wasp Cotesia glomerata (Hymenoptera: Braconidae). Heredity 96:487–492
Acknowledgments
The authors would like to thank the Biotechnology and Biological Sciences Research Council (BBSRC), the Scottish Crop Research Institute (SCRI), The Game and Wildlife Conservation Trust (GWCT) and the University of Dundee (UoD) for providing the funding for this research. We thank Dr Dave Parish and Dr Nick Sotherton (GWCT), and Dr. Alan Barclay (UoD), for support and assistance with sample collection, the landowners for their permission to collect field samples of sawflies and Dr Kelly Houston for helpful comments on the manuscript.
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Cook, N., Hubbard, S.F., Karley, A.J. et al. Genetic diversity and complementary sex determination (CSD) in Dolerus aeneus (Hymenoptera, Symphyta): implications for the conservation of an ecologically-important sawfly. Conserv Genet 14, 1125–1133 (2013). https://doi.org/10.1007/s10592-013-0500-0
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DOI: https://doi.org/10.1007/s10592-013-0500-0