12:15-12:30 23 May 2012
The resolution of species boundaries of four pest members of the Bactrocera dorsalis complex (Diptera: Tephritidae): a multidisciplinary approach Mark Schutze Research Fellow (QUT) biosecurity built on science Cooperative Research Centre for National Plant Biosecurity
Project team Tony Clarke, Mark Schutze, Stephen Cameron, Matt Krosch - QUT, Australia Karen Armstrong & Laura Boykin - Lincoln Uni, New Zealand Toni Chapman, Anna Englezou, Ania Deutscher, Deb Hailstones, Andrew Jessup - New South Wales Primary Industries, Australia Staff of the FAO-IAEA Insect Pest Control Laboratory Seibersdorf - Austria biosecurity built on science
The organism
Bactrocera dorsalis (Oriental fruit fly) B. papayae B. philippinensis B. carambolae
The problem High morphological similarity High genetic similarity Lack of consistent diagnostic markers
Cannot reliably identify these species from each other, or from Australian ‘dorsalis complex’ flies
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Asian papaya fruit fly, B. papayae Drew & Hancock
Oriental fruit fly, B. dorsalis s.s. (Hendel)
Carambola fruit fly, B. carambolae Drew & Hancock
Philippine fruit fly, B. philippinensis Drew & Hancock biosecurity built on science
‘Integrative taxonomic’ approach H0=Four taxa represent one biological species HA=Four taxa represent at least two biological species
Behaviour Sexual compatibility
Genetic analysis Species level Fresh Collections Population level
Morphological Traditional Novel shape analysis biosecurity built on science
Fresh collections B. dorsalis B. philippinensis & B. occipitalis
B. papayae & B. carambolae B. opiliae B. musae B. carambolae
B. cacuminata B. tryoni
Phylogenetic study Combined Bayesian analysis 6 regions (nuclear + mtDNA) ITS1, ITS2, per and CAD CO1, ND4 315 specimens 2221 bp
‘Species-delimitation’ statistics
1) 2) 3) 4) 5)
Inter Dist-closest (K2P) P(Randomly Distinct) Clade Support Rosenberg’s P(AB) P-value
5/5 4/5
Genetics – population level (COI)
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Genetics – population level (Microsats)
B. dorsalis
B. papayae
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Genetics – population level (Microsats)
B. dorsalis
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BEHAVIOUR
B. dorsalis
B. philippinensis
B. papayae
B. carambolae
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Sexual compatibility
B. dorsalis, B. papayae & B. philippinensis Egg viability = 50 - 80%
B. carambolae Egg viability < 50% biosecurity built on science
Wing shape â&#x20AC;&#x201C; species level (24%)
B. philippinensis
B. occipitalis
B. carambolae B. musae
Explains 65%
B. opiliae B. papayae B. cacuminata B. dorsalis (41%) biosecurity built on science
Wing shape – ‘ingroup’ B. philippinensis
B. papayae
B. dorsalis
B. carambolae
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Wing shape â&#x20AC;&#x201C; population level
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Aedeagus morphometrics B. papayae
?
Iwaizumi et al. (1997)
B. dorsalis
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Aedeagus morphometrics
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Summary
Genetics
HA= Two biological species B. dorsalis + B. papayae + B. philippinensis B. carambolae biosecurity built on science
Summary
Genetics Behaviour
HA= Two biological species
HA= Two biological species B. dorsalis + B. papayae + B. philippinensis B. carambolae
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Summary
Genetics Behaviour
HA= Two biological species
Morphological
HA= Two biological species
HA= Two biological species B. dorsalis + B. papayae + B. philippinensis B. carambolae
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Implications Reduce trade barriers Simplify Australian DEED response Better directed AW-IPM & research Full taxonomic revision to await conclusions of FAO-IAEA International Project
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The future… Strengthen international links for offshore diagnostic development
Extend research philosophy & new tools to ‘home-grown’ B. tryoni complex
Develop generic approaches beyond ‘one-complex-at-atime’
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Thank you ď&#x201A;§ For more information, please email m.schutze@qut.edu.au ď&#x201A;§ a.clarke@qut.edu.au
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