Evaluation of the synthetic sex pheromone of the obscure mealybug, P seudococcus viburni , as an attractant to conspecific males, and to females of the parasitoid A cerophagus maculipennis

• Published in: Entomologia experimentalis et applicata Vol. 157; no. 2; pp. 188 - 197
• Main Authors: Charles, John G., Bell, Vaughn A., Hall, Alistair J., Suckling, D. Maxwell, Walker, James T.S., Cole, Lyn M., Shaw, Peter W., Wallis, D. Roger, Millar, Jocelyn G.
• Format: Journal Article
• Language: English
• Published: 01-11-2015
• ISSN: 0013-8703; 1570-7458
• DOI: 10.1111/eea.12355

Abstract
The obscure mealybug,
P
seudococcus viburni
(
S
ignoret) (
H
emiptera:
P
seudococcidae), is a cosmopolitan pest. In
N
ew
Z
ealand, recently introduced management tools include the host‐specific parasitoid
A
cerophagus maculipennis
(
M
ercet) (
H
ymenoptera:
E
ncyrtidae) established in 2001, and pheromone‐baited monitoring traps available since 2005. Red delta traps baited with rubber septum lures impregnated with 4.0 μg of the mealybug synthetic sex pheromone, placed in apple orchards in Hawke's Bay and Nelson, trapped both male
P
. viburni
and female
A
. maculipennis
. Two generations of both species per year were discernible, but numbers were low in spring and parasitoids were not trapped during winter (June to September). Male
P
. viburni
catches reached a plateau at a pheromone dose of ca. 1.0 μg per lure but numbers of
A
. maculipennis
per trap increased up to 100 μg per lure, the maximum dose tested. A mathematical model showed that the lures had a half‐life of about 7.4 days and were most attractive to
P
. viburni
with a dose of 0.19 μg, and that the trap effectiveness decreased rapidly once the release rate dropped below the optimum. The model also predicted that the initial pheromone dose should be increased from 0.19 to 5.41 μg per lure as the desired period of deployment increased from 0 to 9 weeks. A dose of 4.0 μg had an initial relative effectiveness of about 55%, reached peak effectiveness after about 5 weeks, and fell to 55% relative effectiveness again after about 8.3 weeks. We conclude that an initial pheromone load of 4.0 μg is appropriate for practical monitoring of
P
. viburni
during the New Zealand summer. Future applications of the sex pheromone for managing the pest and parasitoid are discussed.