Plant-mediated indirect effects and the persistence of parasitoid-herbivore communities

TY - JOUR

T1 - Plant-mediated indirect effects and the persistence of parasitoid-herbivore communities

AU - Vos, M.

AU - Berrocal, S.M.

AU - Karamaouna, F.

AU - Hemerik, L.

AU - Vet, L.E.M.

N1 - Reporting year: 2001 Metis note: 2798; CL ; CTE; AFW ; MTI ; ME; file:///L:/Endnotedatabases/NIOOPUB/pdfs/Pdfs2001/Vos_ea_2798.pdf

PY - 2001

Y1 - 2001

N2 - We have examined the effects of herbivore diversity on parasitoid community persistence and stability mediated by nonspecific information from herbivore-infested plants. First, we investigated host location and patch time allocation in the parasitoid Cotesia glomerata in environments where host and/or nonhost herbivores were present on Brassica oleracea leaves. Parasitoids were attracted by infochemicals from leaves containing nonhost herbivores. They spent considerable amounts of time on such leaves. Thus, when information from the plant is indistinct, herbivore diversity is likely to weaken interaction strengths between parasitoids and hosts. In four B. oleracea fields, all plants contained herbivores, often two or more species. We modelled parasitoid-herbivore communities increasing in complexity, based on our experiments and field data. Increasing herbivore diversity promoted the persistence of parasitoid communities. However, at a higher threshold of herbivore diversity, parasitoids became extinct due to insufficient parasitism rates. Thus, diversity can potentially drive both persistence and extinctions. [KEYWORDS: behaviour; diversity; extinction; food web; functional response; incomplete information; information network; parasitoids; persistence; redundancy; stability; synomones Infochemical use; c-rubecula; ecology; model; reliability; complexes; stability; systems; context; webs]

AB - We have examined the effects of herbivore diversity on parasitoid community persistence and stability mediated by nonspecific information from herbivore-infested plants. First, we investigated host location and patch time allocation in the parasitoid Cotesia glomerata in environments where host and/or nonhost herbivores were present on Brassica oleracea leaves. Parasitoids were attracted by infochemicals from leaves containing nonhost herbivores. They spent considerable amounts of time on such leaves. Thus, when information from the plant is indistinct, herbivore diversity is likely to weaken interaction strengths between parasitoids and hosts. In four B. oleracea fields, all plants contained herbivores, often two or more species. We modelled parasitoid-herbivore communities increasing in complexity, based on our experiments and field data. Increasing herbivore diversity promoted the persistence of parasitoid communities. However, at a higher threshold of herbivore diversity, parasitoids became extinct due to insufficient parasitism rates. Thus, diversity can potentially drive both persistence and extinctions. [KEYWORDS: behaviour; diversity; extinction; food web; functional response; incomplete information; information network; parasitoids; persistence; redundancy; stability; synomones Infochemical use; c-rubecula; ecology; model; reliability; complexes; stability; systems; context; webs]

U2 - 10.1046/j.1461-0248.2001.00191.x

DO - 10.1046/j.1461-0248.2001.00191.x

M3 - Article

SN - 1461-023X

VL - 4

SP - 38

EP - 45

JO - Ecology Letters

JF - Ecology Letters

IS - 1

ER -