TY - JOUR

T1 - Native parasitoids and their potential to control the invasive leafminer, Cameraria ohridella DESCH. & DIM. (Lep.

T2 - Gracillariidae)

AU - Klug, T.

AU - Meyhöfer, R.

AU - Kreye, M.

AU - Hommes, M.

PY - 2008/8

Y1 - 2008/8

N2 - In spite of the fact that since the end of the eighties, the horse chestnut leafminer, Cameraria ohridella, has established itself throughout Europe, native predators such as ants and birds are not attuned to this neozoic species. In contrast, several parasitic wasp species already started to exploit the invasive horse chestnut leafminer, but until now parasitation rates are quite low, mainly because of asynchrony in the lifecycles of parasitoids and host. Only the removal of leaf litter, in which pupae hibernate, is at the moment a strategy to reduce the infestation level in the next year. Unfortunately, not only hibernating horse chestnut leafminers but also parasitoids are removed, and important resources for biocontrol are unused. In the current study, we investigated the potential efficiency of the horse chestnut leafminer parasitoid complex extracted from leaf litter in defined environments. Parasitoids were released at different densities to investigate density dependence in parasitation rates. Although seven different species were released in our experiments, only Pnigalio agraules turned out to be responsible for biocontrol of C. ohridella. We recorded parasitation rates of up to 35%. Overall, parasitation rates were independent of the leafminer density but increased fourfold if ten times more parasitoid individuals were released. Unfortunately, none of the parasitoid species could be established in the experimental units in the long run. Results are compared to other parasitoid-leafminer systems, and promotion of horse chestnut leafminer parasitoids to support natural selection and biological control of the horse chestnut leafminer is discussed.

AB - In spite of the fact that since the end of the eighties, the horse chestnut leafminer, Cameraria ohridella, has established itself throughout Europe, native predators such as ants and birds are not attuned to this neozoic species. In contrast, several parasitic wasp species already started to exploit the invasive horse chestnut leafminer, but until now parasitation rates are quite low, mainly because of asynchrony in the lifecycles of parasitoids and host. Only the removal of leaf litter, in which pupae hibernate, is at the moment a strategy to reduce the infestation level in the next year. Unfortunately, not only hibernating horse chestnut leafminers but also parasitoids are removed, and important resources for biocontrol are unused. In the current study, we investigated the potential efficiency of the horse chestnut leafminer parasitoid complex extracted from leaf litter in defined environments. Parasitoids were released at different densities to investigate density dependence in parasitation rates. Although seven different species were released in our experiments, only Pnigalio agraules turned out to be responsible for biocontrol of C. ohridella. We recorded parasitation rates of up to 35%. Overall, parasitation rates were independent of the leafminer density but increased fourfold if ten times more parasitoid individuals were released. Unfortunately, none of the parasitoid species could be established in the experimental units in the long run. Results are compared to other parasitoid-leafminer systems, and promotion of horse chestnut leafminer parasitoids to support natural selection and biological control of the horse chestnut leafminer is discussed.

KW - Aesculus hippocastanum

KW - Biological control

KW - Cameraria ohridella

KW - Eulophidae

KW - Horse chestnut leafminer

KW - Parasitoid complex

KW - Pnigalio agraules

UR - http://www.scopus.com/inward/record.url?scp=47649123282&partnerID=8YFLogxK

U2 - 10.1017/S0007485308005695

DO - 10.1017/S0007485308005695

M3 - Article

C2 - 18294419

AN - SCOPUS:47649123282

VL - 98

SP - 379

EP - 387

JO - Bulletin of Entomological Research

JF - Bulletin of Entomological Research

SN - 0007-4853

IS - 4

ER -