Herbivore-species-specific interactions between crucifer plants and parasitic wasps (Hymenoptera : Braconidae) that are mediated by infochemicals present in areas damaged by herbivores
K. Shiojiri et al., Herbivore-species-specific interactions between crucifer plants and parasitic wasps (Hymenoptera : Braconidae) that are mediated by infochemicals present in areas damaged by herbivores, APPL ENT ZO, 35(4), 2000, pp. 519-524
We compared the host-searching behavior of two parasitoid species, Cotesia
plutellae and C. glomerata on their respective host-infested leaf in the la
boratory. We observed the host-searching behavior of C. plutellae on a cabb
age plant infested by the host larvae Plutella xylostella, and found that t
he wasps showed their antennal-searching behavior only on the host-infested
site. The plants and the regurgitant of the host larvae were both involved
in the production of the infochemicals that promoted the antennal-searchin
g behavior in C. plutellae. The searching time of C. plutellae on a piece o
f cabbage leaf infested by host larvae was significantly longer than that o
n a piece infested by nonhost (Pieris rapae) larvae and that on the artific
ially damaged piece. The same pattern in the searching time by C. plutellae
was also observed when we used Japanese radish plants and Rorippa indica p
lants. Likewise, the searching time of C. glomerata on the host (P. rapae)-
infested piece of cabbage or Japanese radish was significantly longer than
that on the piece infested by nonhost (P. xylostella) larvae. Thus, the two
wasp species could detect infestation of these plant species by their resp
ective host through antennal contact.