Species diversity and food web structure jointly shape natural biological control in agricultural landscapes

Abstract

Land-use change and agricultural intensification concurrently impact natural enemy (e.g., parasitoid) communities and their associated ecosystem services (ESs), i.e., biological pest control. However, the extent to which (on-farm) parasitoid diversity and food webs mediate landscape-level influences on biological control remains poorly understood. Here, drawing upon a 3-year study of quantitative parasitoid-hyperparasitoid trophic networks from 25 different agro-landscapes, we assess the cascading effects of landscape composition, species diversity and trophic network structure on ecosystem functionality (i.e., parasitism, hyperparasitism). Path analysis further reveals cascaded effects leading to biological control of a resident crop pest, i.e., Aphis gossypii. Functionality is dictated by (hyper)parasitoid diversity, with its effects modulated by food web generality and vulnerability. Non-crop habitat cover directly benefits biological control, whereas secondary crop cover indirectly lowers hyperparasitism. Our work underscores a need to simultaneously account for on-farm biodiversity and trophic interactions when investigating ESs within dynamic agro-landscapes.

When Does the Prey/Predator Ratio Work for the Effective Biocontrol of Cotton Aphid on Cotton Seedlings?

“…Here, we suppose that the results from C. septempunctata can be generally applicable to the other ladybird beetle species if they were transferred as the natural enemy units [ 48 ]. Moreover, the landscape of cropping had more diversity, and offers the higher percentage of natural enemies in cropping landscapes [ 49 , 50 ]. Soft insecticides prevail in the agricultural production system in China [ 51 ], and the number of insecticides used has been declining rapidly with China’s regulation policies [ 52 ].…”

Transcriptome analysis reveals the proline metabolic pathway and its potential regulation TF-hub genes in salt-stressed potato

“…Genes with |kME| ≥ 0.7 were considered as hub genes in the respective module ( Langfelder and Horvath, 2008 ). The ggcor package in R software was used for correlation testing and visualization ( Yang et al., 2021 ).…”

Functional analysis of odorant-binding proteins for the parasitic host location to implicate convergent evolution between the grain aphid and its parasitoid Aphidius gifuensis

“…For example, parasitized aphid colonies are less attractive than healthy ones [99]. When the species richness of parasitoid wasps increases, the parasitism ratio decreases [100]. Furthermore, both host density and natal host significantly affected the self superparasitism of A. gifuensis on S. miscanthi [51], and the presence of aphid predator chemical cues (such as H. axyridis-related cues) influenced the foraging behavior and activity of A. gifuensis [75].…”