Progress in Japanese Knotweed Biocontrol Research

1. Japanese knotweed biocontrol Progress to date Lindsey Norgrove, Dick Shaw, René Eschen, Ghislaine Cortat, Alex Brook

2. Insect BCA history CBC activity in Europe Weed BCA history • In Europe for Insects there have been more than 300 releases of more than 150 predators and parasitoids with very little regulation

3. Weed CBC - Long and extensive history • Over the past 100 years, more than 400 different biocontrol agents have been used against around 150 target plants, totalling over 1,300 introductions around the globe.

6. Cost of Japanese knotweed to GB 92% of the £166 million annual costs are experienced by the construction and development industry.

7. A consortium of Sponsors came together in 2003 to sponsor the programme

9. Many insects feeding on most parts 186 species of phytophagous arthropod recorded from Japanese knotweed in Japan.

10. Collaboration was essential

11. A process of elimination

14. Aphalara itadori

16. Test Plant List • 90 species and varieties • representatives from 19 families. • 37 plants natives including all native Polygonaceae • 23 species introduced to the UK, • 3 species native to Europe, • 13 ornamental • 10 economically important UK species • No means of agreeing the test plant list in advance!

17. Aphalara adult survival

18. The 78 spp. that did not receive eggs are excluded Bar chart showing mean egg count on those plants that did receive eggs in multiple choice oviposition tests. (+/- 1SE). Development only successful to the left of red line

19. Nymph %survival over time

21. R2= 0.9328 Dev Rate per day = 0.01921+0.002162 Temp DD 462.5 from egg to adult

23. Licensing: The two processes (England) • Licence to release into the wild under the Wildlife and Countryside Act 1981 • Licence to free it from a Plant Health Quarantine license as “an organism likely to be injurious to plants in the UK” - EU Standing Committee on Plant Health were kept informed See also: Hunt et al (2010) An international comparison of invertebrate biological control agent regulation: what can Europe learn? REBECA.

25. 2o & 3o and community level effects? Choice tests with commercially available generalists showed no feeding preference Native coccinellids fed exclusively on psyllids fared worse than when fed on aphids

27. Caged no-choice & Choice experiment • Oviposition and development of A. itadori and non-target impact on F. dumetorum

28. Caged no-choice experiment • Many eggs, some nymphs, limited development F. dumetorum Grey bars eggs, black bars nymphs

29. Comparison with pre-release quarantine multiple-choice tests • Patterns in oviposition similar • No complete development on any non-target species • Very similar to published studies Open field Caged Quarantine 0 (1)% 0 (2)% 0.4% 1.6% 0.2% 1.9% Eggs two (four) weeks after start Redrawn from Shaw (2009)

30. Host-specificity testing Quarantine Caged Open field Multiple choice No-choice Fundamental host range Realised host range Artificial Natural Host-range tests reliably predict non-target attack (Pemberton 2000; Fowler et al. 2000; Barton 2004; Briese 2005) Non-target attack either “predicted” or ephemeral

31. Summary • Caged and open-field studies confirm the host-specificity of Aphalara itadori • No impact of the psyllid on non-target plant species • No impact of A. itadori on native vegetation or invertebrate community • Risk of non-target impact on native vegetation and invertebrates very low

32. No A. itadori found in winter sampling • Typical sample from evergreens contained 100s native psyllids, but no A. itadori • Species sampled included: yew, Pinus spp., Leyland cypress, etc. • Low abundance of A. itadori at release sites  larger releases required for establishment

33. Successful overwintering!!

34. Mass-producing psyllids • Two production cycles: • First in cages inside Controlled environment

35. Mass-producing psyllids • Data loggers allow checks on development • Insects to be ready for releases in last two weeks in May

36. What can we expect? • If successful: • Establishment of the agent • Spread to JK • Reduced plant vigour • Reduced control costs • Recovery of native species • Control not eradication!

37. EU opportunitiesSheppard, Shaw & Sforza - Weed Research 2006

38. Hydrocotyle ranunculoides Photo – T. Renals

40. Impatiens glandulifera

41. Puccinia rust

42. Dr Harry Evans (CABI), Dr Marion Seier & Dr Rob Reeder Rob Tanner (CABI) Djamila Djeddour (CABI) Dr Carol Ellison Drs Murphy, Cock and Holderness (CABI) Ghislaine Cortat (CABI) Dr Rene Eschen Anna Harris Sonal Varia Corin Pratt Alex Brook Dr Esther Gerber Valérie Coudrain & Sarah Bryner (CABI tudents) Sasha White Dr Paul Cannon and Dr Alan Buddie (CABI) Linda Birken (Imperial College student) Gareth Martin (Imperial College student) James Broom (Imperial College student) Dr John Bailey and Kat Pashley (Leicester University) Dr Lois Child (Loughborough University) Dr Andy Polaszek & others (NHM) Professor Masami Takagi (Kyushu University) Dr Daisuke Kurose (Kyushu University) Dr Narutu Furuya (Kyushu University) Dr Naoki Takahashi (Kyushu University) Yuko Inoue (Kyushu University) Dr Fritzi Grevstad (University of Washington) Dr Bernd Blossey (Cornell University) Dr Rob Bouchier (AAFC Canada) Dr Brian Van Hezelwink (AAFC Canada) Victoria Nuzzo (Independent Consultant) Mic Julien (CSIRO) Dr Andy Sheppard (CSIRO) Dr Simon Fowler (Landcare Research NZ) Drs Ted Centre & Gary Buckingham (Florida Uni) Profs Mick Crawley &Tim Coulson (Imperial College) Dr Willie Cabrera Walsh (SABCL) Dr Jonathan Newman (CEH) Dr Usha Dev (NBPGR) Dr Ravi Kheterpal (NBPGR) Dr Robin Adair (DPI Queensland) Drs John Ireson & Richard Holloway (Utas) Lindsay Smith (Landcare Research) ACRE FERA – many especially Dr Claire Sansford Pesticide Safety Directorate The Non Native Species Secretariat The Project Board and sponsors for funding and guidance Thank you to all involved

43. Thank You • Any Questions?