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Tephritid Barcoding Initiative and barcoding of agricultural pest. presented by M. Virgilio Royal Museum for Central Africa, Tervuren, Belgium Royal Belgian Institute of Natural Sciences, Brussels, Belgium m.virgilio@skynet.be.
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Tephritid Barcoding Initiative and barcoding of agricultural pest presented by M. Virgilio Royal Museum for Central Africa, Tervuren, Belgium Royal Belgian Institute of Natural Sciences, Brussels, Belgium m.virgilio@skynet.be Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
Why DNA Barcode Fruit Flies? • large number of species • many economically relevant species • difficult identification of larvae. • need for standardized diagnostic methods Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
The Tephritid Barcode Initiative (TBI) • CBOL obtained funding from the Sloan Foundation • to support a “Demonstrator System” • Steering Committee formed in April, 2006, in Belgium Steering Committee Members: Karen Armstrong, New Zealand Norman Barr, USA Amnon Freidberg, Israel Ho-Yeon Han, South Korea George Roderick, USA Ian White, UK TBI Chair: Bruce McPheron, Penn State TBI Coordinators: Allen Norrbom, USDA, USA Marc De Meyer, RMCA, Belgium Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
TBI proposal: Goals Generate barcode database for 2,000 species • 5 individuals/species (10,000 specimens) • 100% of economically important (EI) species • >75% of EI congeners • 1 species per genus in subtribes containing EI species • 1 species per genus in other higher taxa • representative tephritoid families Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
TBI proposal: Beneficial Outcomes 1) Establish a globally-available DNA database of barcodes 2) Establish a globally-available DNA repository 3) Generate a collection of identified vouchers for future systematic work Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
Who is generating fruit fly barcodes? • Penn State University, USA: Bruce McPheron, Md. Sajedul Islam • Lincoln University, New Zealand: Karen Armstrong • Royal Museum Central Africa, BE: Marc De Meyer, Massi Virgilio • Yonsei University, Korea: Ho-Yeon Han • California Department of Agriculture, USA: Peter Kerr • Smithsonian National Museum of Natural History, USA: Allen Norrbom • APHIS-PPQ Mission lab, USA: Norman Barr • University of Guelph • Biodiversity Institute of Ontario Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
Financial support Penn State University, USA: technical support APHIS: collecting & sequencing Belgian Federal Government: sequencing, pilot study mini-barcodes California Citrus Board: general expenditure Korean Government: sequencing (Dutch Government: collecting) Various contributions through staff time and general core funding of institutions or other projects Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
What needs to be provided in BOLD for TBI • identification of specimen by an expert taxonomist • voucher specimen • collection information (collection date and location) • other infos (GPS, elevation, photodocumentation) not mandatorybut strongly encouraged • barcode: at least 500bp with less than 1% missing data. • trace files stored in BOLD. Euleia fratria (Trypetinae)TEPH101 (from BOLD) Other COI records (e.g., Genbank submissions) are integrated into the BOLD database but kept separate. Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
http://www.barcodinglife.org Tephritidae {family} Barcodes : Species : Search performed on October 20, 2008 Lineage: Arthropoda: Insecta: Diptera Specimen Record: 1047 Specimens with barcodes: 828 Public Sequences: 240 Subfamilies (5) Dacinae [572] Phytalmiinae [7] Tachiniscinae [1] Tephritinae [219] Trypetinae [243] Deposited in :
all species EI species % of species barcoded 100 80 60 40 20 0 Dacus Ceratitis Rhagoletis Bactrocera Anastrepha Five Genera of Highest Economic Importance number of species 600 533 400 240 213 200 119 95 73 44 37 34 19 0 Dacus Ceratitis Rhagoletis Bactrocera Anastrepha
insights into DNA barcoding of tephritid fruitflies Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
intra- and inter-specific genetic differentiation in 3 genera of tephritid fruitflies ratio inter/intra specific p-dist 12.6 6.3 6.6 20% 16% p-distances 12% between species 8% within species 4% 0% Bactrocera Ceratitis Dacus Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
DNA barcoding of tephritid fruitflies: where it works nicely.... 44 barcodes of Bactrocera cucurbitae from 11 countries: • Bangladesh • Cambodia • China • Hawaii • India • Kenya • La Reunion • Malaysia • Philippines • Sudan • Tanzania average genetic distance within species K2p = 0.02% (S.E.= 0.01%)
... and where not: the FAR complex Ceratitis fasciventris C. anonae C. rosa average genetic distances 0.02 K2P 0.01 between species within species 0.00 ratio = 1.2
other potentially “problematic” tephritid species groups and complexes: B. dorsalis complex C. cosyra complex C. capitata / C. caetrata T. occipitale / T. quadrimaculatum ... Armstrong and Ball (2005) Phil. Trans. R. Soc. B 360: 1813-1823. (B. dorsalis complex) Virgilio et al. (2008) Molecular Phylogenetic and Evolution 48: 270-280 (FAR complex, Ceratitis)
Dacus: from identification issues to classification issues as expected low genetic differentiation in taxonomicallycloserspecies... D. chiwira - D. famona, p-dist.= 0.3%(subgenus Dacus) D. apostata - D. triater, p-dist.= 0.0% (subgenus Psilodacus)
DACUS DIDACUS LEPTOXYDA LOPHODACUS NEODACUS PSILODACUS COI NJT-K2P ...but also discrepancies between morphological and molecular taxonomy subgeneric classification
Apocynaceae Cucurbitaceae Passifloraceae unknown DNA barcoding may provide clues for an improved morphological classification host plant choice COI+16S+per Bayesian
DNA barcoding may reveal cryptic speciation: Virgilio M., De Meyer M, WhiteI.M., Backeljau T. (submitted) Phylogenetic relationships among African Dacus species (Diptera: Tephritidae) as inferred from mitochondrial and nuclear DNA.
methodological problems in the barcoding of tephritid fruitflies from museum collections Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
methodological problems in the barcoding of museum specimens DNA Extraction Procedures: Several pilot studies performed to assess the success of an invasive, nondestructive DNA extraction method for museum specimens. Study 1: L. Weigt and A. Driskell (Laboratory of Analytical Biology, National Museum of Natural History, Smithsonian Institution) -16S and COI Study 2: N. Barr (USDA) and R. Ruiz (Penn State) -16S Study 3. M. Virgilio (Royal Museum Central Africa, BE) – 16S, COI Study 4. Md. Sajedul Islam (Penn State) - COI (ongoing study) Qiagen DNeasy kit: ok for DNA from recent dry and alcohol specimens not crushed during the extraction process. Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
100 % specimens amplified 80 % specimens sequenced 60 40 20 0 90s 80s 2007 2006 2005 2004 2003 2002 2001 2000 < 1980 methodological problems in the barcoding of museum specimens age of specimens vs barcoding success (n=394)
100 from EtOH specimens 80 from pinned specimens 60 40 20 0 < 1980 2007 2006 2005 2004 2003 2002 2001 2000 90s 80s methodological problems in the barcoding of museum specimens pinned vs EtOH preserved specimens % of succesfully sequenced specimens (n=394)
<1940 >2000 32% 41% 40s 4% 50s 90s 80s 13% 70s 4% 3% 1% 60s 2% methodological problems in the barcoding of museum specimens Ceratitis, Bactrocera and Dacus in the collections of the RMCA: (n=1804)
methodological problems in the barcoding of museum specimens DNA extraction protocols tested: • Qiagen DNeasy • Qiagen Biosprint • Bio101 Ancient DNA kit • Autogen • Machery-Nagel Filterservice kit • Phenol-Chloroform • DNAzol • E.Z.N.A. kits for forensics and insects • chargeswitch magnetic beads • etc. Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
methodological problems in the barcoding of museum specimens • problem: • the quality of DNA rapidly decreases in time (shearing) • the amount of barcodes obtained from older museum specimens is not significantly affected by • the extraction method used • the use of genus- and species-specific primers • objective: • develop internal primers to improve the collection of barcodes from sheared DNA Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
methodological problems in the barcoding of museum specimens • the BARFLY project • short term project funded by the Belgian Science Policy (BELSPO) • Joint Experimental Molecular Unit • of RMCA and RBINS (www.jemu.be) • Jeroen Van Houdt,Floris Breman • development of internal primers for the barcoding of Tephritids • collection of new barcodes from museum specimens Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
LCO 1490 HCO 2198 full barcode - c. 670 bp frag. 1 - 343bp frag. 2 - 269bp frag. 3 - 227bp a new set of internal primers for the barcoding of tephritids VanHoudt J., Breman F. C., Virgillio M.,De Meyer M. (in prep.) A protocol for DNA barcoding of African tephritid fruitflies from museum collections using mini barcodes.
100 (n=229) 80 60 40 fragment 1 20 fragment 2 0 >2000 90s 80s 70s 60s 50s 40s <1940 fragment 3 100 . (n=229) 80 60 40 20 0 >2000 90s 80s 70s 60s 50s 40s <1940 % of pcr products obtained % of barcode sequences obtained (>500bp)
+7% +32% +6% +7% 100 80 60 standard primers 40 internal primers 20 (n=229) 0 >2000 90s 80s <1980 a new set of internal primers for the barcoding of tephritids higher performances compared to the standard primers % of barcodes obtained (>500bp)
a new set of internal primers for the barcoding of tephritids RMCA: internal primers as a standard protocol for the barcoding of museum specimens collected before 2000 Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
work in progress: could ‘minibarcodes’represent a temporary alternative to ‘full’ barcodes? Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
Dacus armatus 400 bp 400 bp 500 bp 600 bp 400 bp Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
Bactrocera oleae 500 bp 300 bp 400 bp Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
TBI current challenges • Coordination / tracking specimens: BOLD • Older specimens: mini barcodes / internal primers • Fresh material: collecting activities • Taxon coverage: non EI genera Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences
RMCA current challenges RMCA is collecting barcodes as a “complementary activity” to the currently ongoing research lines: • phylogeny and population genetics of African Dacus • molecular taxonomy of species complexes in the genus Ceratitis • phylogeny of African and Australasian Bactrocera • population genetics and phylogeography of B. cucurbitae Marc De Meyer: marc.de.meyer@africamuseum.be Massimiliano Virgilio: m.virgilio@skynet.be contact:
RMCA current challenges RMCA is opened tocollaborations with African Institutions aiming to: • identify tephritid samples through morphological and molecular characters • prepare species inventories from African countries • collect / rear tephritid fruit flies • investigate population genetics and host races evolution of tephritid species Marc De Meyer: marc.de.meyer@africamuseum.be Massimiliano Virgilio: m.virgilio@skynet.be contact:
Acknowledgments Karen Armstrong Abdelaziz Babikir Thierry Backeljau Norman Barr Marc DeMeyer Sajedul Islam Bruce McPheron researches at the RMCA are currently funded by the Belgian Science Policy Action 1 (project MO/37/017) and benefit from practical support by the Joint Experimental Molecular Unit (JEMU) Royal Museum for Central Africa – Royal Belgian Institute of Natural Sciences