Attraction and antennal response of the common wasp, Vespula vulgaris (L.), to selected synthetic chemicals in New Zealand beech forests.
BACKGROUND
The common wasp, Vespula vulgaris (L.), and the German wasp, Vespula germanica (F.), are significant problems in New Zealand beech forests (Nothofagus spp.), adversely affecting native birds and invertebrate biodiversity. This work was undertaken to develop synthetic attractants for these species to enable more efficient monitoring and management.


RESULTS
Seven known wasp attractants (acetic acid, butyl butyrate, isobutanol, heptyl butyrate, octyl butyrate and 2,4-hexadienyl butyrate) were field tested, and only heptyl butyrate and octyl butyrate attracted significantly higher numbers of wasps than a non-baited trap. Accordingly, a series of straight-chain esters from methyl to decyl butyrate were prepared and field tested for attraction of social wasps. Peak biological activity occurred with hexyl butyrate, heptyl butyrate, octyl butyrate and nonyl butyrate. Polyethylene bags emitting approximately 18.4-22.6 mg day(-1) of heptyl butyrate were more attractive than polyethylene bags emitting approximately 14.7-16.8 mg day(-1) of heptyl butyrate in the field. Electroantennogram (EAG) studies indicated that queens and workers of V. vulgaris had olfactory receptor neurons responding to various aliphatic butyrates.


CONCLUSIONS
These results are the first to be reported on the EAG response and the attraction of social wasps to synthetic chemicals in New Zealand beech forests and will enable monitoring of social wasp activity in beech forests.
El-Sayed
Ashraf M
AM
The Horticulture and Food Research Institute of New Zealand Limited, Canterbury Research Centre, Lincoln 7608, New Zealand. ael-sayed@hortresearch.co.nz
Manning
Lee-Anne
LA
Unelius
C Rikard
CR
Park
Kye Chung
KC
Stringer
Lloyd D
LD
White
Nicola
N
Bunn
Barry
B
Twidle
Andrew
A
Suckling
David M
DM
D000818:Animals; D002087:Butyrates / Q000138:chemical synthesis; D017753:Ecosystem; D029964:Fagus; D007300:Insect Control; D009520:New Zealand; D014863:Wasps / Q000502:physiology*
D002087:Butyrates