The landscape context of cereal aphid-parasitoid interactions
Carsten Thies1, Indra Roschewitz, Teja Tscharntke
1Department of Agroecology, Georg-August-University Göttingen, Waldweg 26, 37073 Göttingen, Germany. c.thies@uaoe.gwdg.de
Abstract:
Analyses at multiple spatial scales may show how important ecosystem services such as biological control are determined by processes acting on the landscape scale. We examined cereal aphid-parasitoid interactions in wheat fields in agricultural landscapes differing in structural complexity (32-100% arable land). Complex landscapes were associated with increased aphid mortality resulting from parasitism, but also with higher aphid colonization, thereby counterbalancing possible biological control by parasitoids and lastly resulting in similar aphid densities across landscapes. Thus, undisturbed perennial habitats appeared to enhance both pests and natural enemies. Analyses at multiple spatial scales (landscape sectors of 0.5-6 km diameter) showed that correlations between parasitism and percentage of arable land were significant at scales of 0.5-2 km, whereas aphid densities responded to percentage of arable land at scales of 1-6 km diameter. Hence, the higher trophic level populations appeared to be determined by smaller landscape sectors owing to dispersal limitation, showing the 'functional spatial scale' for species-specific landscape management.
More Related Videos
07:20Maintaining Biological Cultures and Measuring Gene Expression in Aphis nerii: A Non-model System for Plant-insect Interactions
Published on: August 31, 2018
08:28Assessment of Aphidicidal Effect of Entomopathogenic Fungi against Parthenogenetic Insect, Mustard Aphid, Lipaphis erysimi (Kalt.)
Published on: July 21, 2023
Related Concept Videos
Symbiosis
Predator-Prey Interactions
Epiphytes, Parasites, and Carnivores
Microbial Interactions: Cooperation
Microbial Interactions: Parasitism
Microbe-Plant Interactions
