Faculty of Environmental Sciences, Department of Forest Science, Chair of Forest Protection

Economic importance and natural enemies of the red poplar leaf beetle ( L.) in poplar short rotation coppice in Germany

Vancouver, 2014-07- 22 Outline

Part I The red poplar leaf beetle (Chrysomela populi L.)

Part II Economic importance of C. populi

Part III Natural enemies of C. populi

Part IV Future perspectives

2014-07-22 Economic importance and natural enemies of C. populi Slide 2 of 10 Part I The red poplar leaf beetle Part II Economic importance Part III Natural enemies Part IV Future perspectives

(great) red poplar leaf beetle imagoes on sprouting cutting (Chrysomela populi)

¾two generations per years ¾larvae and imagoes feed on young leaves ¾main pest species in poplar SRC, esp. on ‘Max’ varieties ¾benefits from the short rotation lengths (3-5 years)

imagoes on sprouting stool after harvesting

2014-07-22 Economic importance and natural enemies of C. populi Slide 3 of 10 Part I The red poplar leaf beetle Part II Economic importance Part III Natural enemies Part IV Future perspectives

Larvae of C. populi

?

height biomass cuttings damage on apical leafs quality undamaged poplar

2014-07-22 Economic importance and natural enemies of C. populi Slide 4 of 10 Part I The red poplar leaf beetle Part II Economic importance Part III Natural enemies Part IV Future perspectives

Others applicatio n of pesticides

Preliminarily results Δ Height = 13% (322/279 cm) Δ Biomass = 15% (7.07/6.00 odt*ha‐1) Δ Cuttings = 21% (22.23/17.47 cuttings per stool)

Influence of feeding of C. populi on weekly height growth of Max 3 (n=120 stools per category in four blocks)

2014-07-22 Economic importance and natural enemies of C. populi Slide 5 of 10 Part I The red poplar leaf beetle Part II Economic importance Part III Natural enemies Part IV Future perspectives

nigritarsis bug Picromerus bidens

chalcid wasp Schizonotus sieboldi mite Linobia coccinellea

parasitised pupae by tachinid Cleonice callida

hoverfly P. nigritarsis

2014-07-22 Economic importance and natural enemies of C. populi Slide 6 of 10 Part I The red poplar leaf beetle Part II Economic importance Part III Natural enemies Part IV Future perspectives

Linobia coccinellae

¾exoparasitic mite, sucking on haemolymph ¾colonization of new host mainly during copulation

¾fast increasing parasitation rate and density transmission

high densities

Mean number of different development stages of Linobia coccinellae on imagoes electron microscope photograph of C. populi on three different dates; error bars representing standard deviation

2014-07-22 Economic importance and natural enemies of C. populi Slide 7 of 10 Part I The red poplar leaf beetle Part II Economic importance Part III Natural enemies Part IV Future perspectives

Parasyrphus nigritarsis

● development stage 600 egg cluster ● L1

400 year ● 2012 elopment stage v 2013

200 ● mber of de

u ●

n ● ● ● ● ● 0 ●● ●

Apr 22 Apr 29 May 06 May 13 May 20 May 27 date Development of larvae of Parasyrphus nigritarsis and Comparison of the development from egg cluster to first influence on egg cluster of C. populi larval stage in 2012 and 2013. The low number of larvae in 2013 could trace back to the high predation rate of eggs by the hoverfly Parasyrphus nigritarsis.

2014-07-22 Economic importance and natural enemies of C. populi Slide 8 of 10 Part I The red poplar leaf beetle Part II Economic importance Part III Natural enemies Part IV Future perspectives

Integrated pest management strategy for C. populi

2014-07-22 Economic importance and natural enemies of C. populi Slide 9 of 10 Thank you for listening!

Contact: Richard Georgi TU Dresden Chair of Forest Protection Pienner Str. 8 01737 Tharandt http://www.agrofornet.de 035203/3831623 www.tu‐dresden.de/forst/waldschutz

2014-07-22 Economic importance and natural enemies of C. populi Slide 10 of 10