title: Larval hitch-hiking and adult flight are two ways of aphidiinae parasitoids long-range dispersal.
abstract: Dispersal strategies and success of pests' natural enemies widely influence the efficiency of biological control. In this study, we compare two dispersal strategies among Aphidiinae parasitoids: eggs and larvae dispersal through winged aphid flight and active dispersal by adult parasitoids. Using a molecular method applied to a sample of >2,000 winged migratory aphids captured in a suction trap situated in Western France, we assessed the proportion of winged aphids carrying an aphidiine larva. In the six most abundant aphid species, we found an average parasitism rate of migrating aphids close to 1% and identified seven different, mainly generalist, parasitoid species. We also identified the species and the sex of adult Aphidiinae captured by the suction trap based on morphological criteria. We found that dispersing adult parasitoids were almost exclusively female. Parasitoid dispersal strategy seems to be species-dependant but this result needs to be confirmed by an exhaustive analysis of winged aphids captured. We discuss the possible impact of the low parasitism rate of winged aphids on parasitoid population dynamics and the importance of these results in the context of biological control and of the study of food webs between aphids and their natural enemies.
authors.affiliation: AGROCAMPUS OUEST, UMR1349 IGEPP, F-35000 Rennes, France.
authors.forename: Stéphane A P
authors.initials: SA
authors.lastname: Derocles
authors.forename: Manuel
authors.initials: M
authors.lastname: Plantegenest
authors.forename: Evelyne Turpeau
authors.initials: ET
authors.lastname: Ait-Ighil E
authors.forename: Bernard
authors.initials: B
authors.lastname: Chaubet
authors.forename: Charles-Antoine
authors.initials: CA
authors.lastname: Dedryver
authors.forename: Anne
authors.initials: A
authors.lastname: Le Ralec
mesh_terms: D063147:Animal Distribution; D000818:Animals; D001042:Aphids / Q000469:parasitology*; D005260:Female; D005426:Flight, Animal; D020387:Food Chain; D005602:France; D006790:Host-Parasite Interactions; D007814:Larva; D008297:Male; D009758:Nymph; D011157:Population Dynamics; D013045:Species Specificity; D014863:Wasps / Q000502:physiology*