Optimising Eradications Lloyd Stringer Research Associate- Biosecurity biosecurity built on science Cooperative Research Centre for National Plant Biosecurity
The Team
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The Team
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The Team
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The Team
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LBAM incursion California
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Optimising eradications Radiation Biology - Epiphyas postvittana light brown apple moth (LBAM)
Fitness effects - From irradiation
Modelling - Identifying optimal release strategy based on full and inherited sterility (IH) biosecurity built on science
Radiation Biology  Determine dose required for full and inherited sterility (IH) for both male and female pupae of light brown apple moth Epiphyas postvittana
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Radiation Biology  >95% egg sterility in female at 250Gy, males 300Gy  Skewed sex ratio (3:1) in favour of males in male IH line only
Soopaya et al. 2011 JEE biosecurity built on science
Radiation Biology No IH for females IH only at F1 stage F1 males >95% sterile above 200Gy What are fitness costs?
Soopaya et al. 2011 JEE biosecurity built on science
Fitness effects  Physical fitness- flight competitiveness lure - Does irradiation reduce flight ability?
 Physical fitness- flight competitiveness females - Who reaches the female first?
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Fitness effects  Physical fitness- flight competitiveness lure - Does irradiation reduce flight ability?
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Fitness effects
Suckling et al. 2011 JEE
 Physical fitness- flight competitiveness lure - Does irradiation reduce flight ability?
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Fitness effects
Suckling et al. 2011 JEE
 Physical fitness- flight competitiveness lure - Does irradiation reduce flight ability?
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Fitness effects  Physical fitness- flight competitiveness females - Who reaches the female first?
 Distinguishing released moths V wild moths to determine introgression of sterility into population. - Dyes external
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Fitness effects  Physical fitness- flight competitiveness females - Who reaches the female first?
 Distinguishing released moths V wild moths to determine introgression of sterility into population. - Dyes external - Dyes internal
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Fitness effects Physical fitness- flight competitiveness females - Who reaches the female first?
Distinguishing released moths V wild moths to determine introgression of sterility into population. - Dyes external - Dyes internal
Post copulation - Histology
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Fitness effects Physical fitness- flight competitiveness females - Who reaches the female first?
Distinguishing released moths V wild moths to determine introgression of sterility into population. - Dyes external - Dyes internal
Post copulation - Histology - Stable isotopes
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Fitness effects Physical fitness- flight competitiveness females - Who reaches the female first?
Stable isotopes ratio 13C or 15N based on diet Wild and reared moths were separated by stable isotope C13 δ15N vs air 0
2
4
6
8
10
12
14
-15 -17 -19 δ13C vs VPDB
-21
Mass reared moths
-23 -25 -27 -29
Wild moths
-31 -33 -35
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Fitness effects Physical fitness- flight competitiveness females - Who reaches the female first?
Pheromone lures & caged females placed out in a vineyard Bi-sex release of 250Gy irradiated moths
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Fitness effects  Physical fitness- flight competitiveness females - Who reaches the female first?
 Irradiated males represents 40% moths in lure traps, only were ~15% in mated females
Proportion of E. postvittana
1 0.9 0.8 0.7 0.6 0.5
Wild
0.4
Irradiated
0.3 0.2 0.1 0
Control Plot
Release Plot
Spermatophores from females
Control Plot
Release Plot
Control Plot
Release Plot
Male catch to females Male catch to synthetic lures
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Modelling
Kean et al. 2011
 Determining number of moths required for eradication success with full and inherited sterility - Relative competiveness
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Modelling
Kean et al. 2011
ď&#x201A;§ Determining eradication success with full and inherited sterility - Relative competiveness - Self sustaining population <171Gy
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Modelling
Kean et al. 2011
ď&#x201A;§ Determining eradication success with full and inherited sterility - Relative competiveness - Self sustaining population <171Gy - Overflooding ratio in traps 6.4 = >95% eradication (300Gy) - Optimal dose for eradication 200Gy to use IH thus reducing factory moths by ~1/3
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Conclusions Inherited sterility is a more efficient use of resources than full sterility - Decreasing rearing costs - Increasing flight fitness
Full sterility good end-game tactic Stable isotopes good for determining integration of one population into another population Next step->Integrating eradication tactics
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Team list Bill Woods Max Suckling, Lloyd Stringer, Alven Soopaya, John Kean, Eric Jang, Amandip Kaur, Ian Lacey, Anne Barrington, Ashraf El-Sayed, Delyse Campbell, Vanessa Mitchell, Lee-Anne Manning, Ruth Butler, Andrea Stephens, Suk-Ling Wee, Tom Sullivan, Nicola Sullivan, Greg Simmons, Rebecca Hood-Nowotny, Ecki Brockerhoff, Jess Kerr, David Williams, Greg Baker, Latif Salehi.
lloyd.stringer@plantandfood.co.nz biosecurity built on science
Thank you
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