Bulletin of Entomological Research (2004) 94, 411-417

S.L. Goldson, J.R. Proffitt, M.R. McNeill, C.B. Phillips, N.D. Barlow and D.B. Baird (2004)
Unexpected Listronotus bonariensis (Coleoptera: Curculionidae) mortality in the presence of parasitoids
Bulletin of Entomological Research 94 (5), 411-417
Abstract: Field enclosure and laboratory cage experiments designed to measure the impact of the parasitoid Microctonus hyperodae Loan on the Argentine stem weevil, Listronotus bonariensis (Kuschel) have shown that under high parasitoid pressure, there is significant weevil mortality without obvious parasitism. Parasitoid-exposed, but unparasitized portions of caged populations died at rates significantly higher than both the parasitized weevils from the same population and the unexposed controls. Unexpectedly, parasitized weevils had the lowest mortality rates (prior to larval parasitoid emergence). It was of ecological significance that this mortality effect was detected under field conditions using several years of empirically-collected population dynamics data. Under both field and laboratory conditions this mortality was found to occur within shorter time intervals than that required for full parasitoid larval development; thus it could not be attributed to the mortality that occurs after the emergence of prepupal parasitoids. The mechanism for this mortality remains undetermined, although it could possibly be linked to pseudoparasitism.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Stephen L. Goldson, Nigel D. Barlow, Mark R. McNeill, Craig B. Phillips

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Listronotus bonariensis	Grasses/turf/rangeland	New Zealand
Microctonus hyperodae (parasitoid)	Listronotus bonariensis	Grasses/turf/rangeland	New Zealand