Optimising eradications

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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