Abstract
Plants can recruit parasitic wasps in response to egg deposition by
herbivorous insects¿a sophisticated indirect plant defense mechanism.
Oviposition by the Large Cabbage White butterfly Pieris
brassicae on Brussels sprout plants induces phytochemical changes
that arrest the egg parasitoid Trichogramma brassicae. Here, we
report the identification of an elicitor of such an ovipositioninduced
plant response. Eliciting activity was present in accessory
gland secretions released by mated female butterflies during egg
deposition. In contrast, gland secretions from virgin female butterflies
were inactive. In the male ejaculate, P. brassicae females
receive the anti-aphrodisiac benzyl cyanide (BC) that reduces the
females¿ attractiveness for subsequent mating. We detected this
pheromone in the accessory gland secretion released by mated
female butterflies. When applied onto leaves, BC alone induced
phytochemical changes that arrested females of the egg parasitoid.
Microarray analyses revealed a similarity in induced plant responses
that may explain the arrest of T. brassicae to egg-laden
and BC-treated plants. Thus, a male-derived compound endangers
the offspring of the butterfly by inducing plant defense. Recently,
BC was shown to play a role in foraging behavior of T. brassicae,
by acting as a cue to facilitate phoretic transport by mated female
butterflies to oviposition sites. Our results suggest that the antiaphrodisiac
pheromone incurs fitness costs for the butterfly by
both mediating phoretic behavior and inducing plant defense.
Original language | English |
---|---|
Pages (from-to) | 10033-10038 |
Journal | Proceedings of the National Academy of Sciences of the United States of America |
Volume | 105 |
DOIs | |
Publication status | Published - 2008 |
Keywords
- parasitic wasps
- pierid butterflies
- oral secretions
- gene-expression
- host location
- atp synthase
- insect
- elicitors
- volatiles
- oviposition