Landscape composition mediates suppression of major pests by natural enemies in conventional cruciferous vegetables

Pest Management Science

Sun

Pozsgai

et al. 2022

Self Cite

BACKGROUND: Understanding the networks of trophic interactions into which generalist predators are embedded is key to assessing their ecological role of in trophic networks and the biological control services they provide. The advent of affordable DNA metabarcoding approaches greatly facilitates quantitative understanding of trophic networks and their response to environmental drivers. Here, we examine how key environmental gradients interact to shape predation by Lycosidae in highly dynamic vegetable growing systems in China.RESULTS: For the sampled Lycosidae, crop identity, pesticide use and seasons shape the abundance of prey detected in spider guts. For the taxonomic richness of prey, local-and landscape-scale factors gradients were more influential. Multivariate ordinations confirm that these crop-abundant spiders dynamically adjust their diet to reflect environmental constraints and seasonal availability to prey. CONCLUSION: Plasticity in diet composition is likely to account for the persistence of spiders in relatively ephemeral brassica crops. Our findings provide further insights into the optimization of habitat management for predator-based biological control practices.

Section: Discussionmentioning

confidence: 99%

DNA metabarcoding of gut contents reveals key habitat and seasonal drivers of trophic networks involving generalist predators in agricultural landscapes

Pest Management Science

Sun

Pozsgai

et al. 2022

Self Cite

“…small streams or ponds) (Figure 1b). The proportion of different land use types was calculated for five different spatial scales, 100, 200, 300, 400, and 500 meter radius around the focal field, by using QGIS 3.4 (for details, see Zhang et al (2021)).…”

Section: Methodsmentioning

confidence: 99%

“…They were set at each site in the same pattern as the pan traps. Besides pitfall traps, boat-shape traps with a sex pheromone lure were set to sample Plutella xylostella (Linnaeus, 1758) males (Zhang et al, 2021). All specimens were transferred into 80% ethanol in tubes and identified to the lowest possible taxonomic level using the molecular barcoding procedures given by Saqib et al (2022).…”

Section: Methodsmentioning

confidence: 99%

“…Indeed, other than a few examples, the majority of the studies on the effects of functional diversity on ecosystem functioning were conducted on a fine (and/or a single) spatial scale (Gonzalez et al, 2020). Although Zhang et al (2021) showed varying effects of habitats on the taxonomic diversity of arthropod communities across five different spatial scales in managed brassica vegetables, it is largely unknown if these changes in taxonomic diversity are accompanied by similar trends in functional diversity.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Contrasting roles of landscape compositions in shaping functional traits of arthropod community in subtropical vegetable fields

Zhang

Niu

et al. 2022

Preprint

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Agricultural intensification and land use transformation are among the main driving forces of the unprecedented decline of biodiversity and ecosystem services in croplands. Trait-based approaches provide a unique framework to detect the potential mechanisms of how this intensification affects biodiversity and alter ecosystem services. However, the potential relationship between arthropod traits and various types of habitats is still poorly understood, especially in subtropical vegetable agroecosystems.Here, we conducted a trait-based approach to evaluate the variable roles of different habitats on functional trait diversity and the structure of the arthropod community in brassica vegetable crops. Twenty-three conventional cruciferous vegetables fields were sampled over two years in three regions in Fujian, China. We found that the increasing proportion of non-brassica vegetable plantations and water bodies negatively affected the functional diversity of arthropods, whereas forest and grassland habitats showed a positive correlation, indicating habitat filtering for certain traits or trait combinations.This study demonstrates the importance of landscape composition as an ecological filter for vegetable arthropod community, and identifies how the proportion of different habitats selected for or against specific functional traits. Our findings support that increasing forest and grassland areas adjacent to vegetable fields can play a vital role in promoting the functional diversity of arthropod communities. Since the natural enemy assemblages supported by these habitats bear combinations of diverse traits adapted to disturbance, they have the potential to enhance pest suppression in the highly variable environment of vegetable crops.

“…The availability of semi-natural habitats (e.g. patches of grassland) and non-brassica crops (eg., pepper, eggplant, corn, and beans) in the surrounding landscape can significantly increase the abundance and prey species diversity 65 in the gut of spiders captured on crop fields. These observed effects of semi-natural habitats and crops with longer duration were likely due to the availability of a stable understory habitat with a high diversity of plants that harbor alternative prey resources for generalist predators 66,67 .…”

Section: Local and Landscape Factors As Determinants Of Prey Species ...mentioning

confidence: 99%

DNA metabarcoding of gut contents reveals key habitat and seasonal drivers of trophic networks involving generalist predators in agricultural landscapes

Sun

Pozsgai

et al. 2022

Preprint

Self Cite

BACKGROUNDUnderstanding the networks of trophic interactions into which generalist predators are embedded is key to assessing their ecological role of in trophic networks and the biological control services they provide. The advent of affordable DNA metabarcoding approaches greatly facilitates quantitative understanding of trophic networks and their response to environmental drivers. Here, we examine how key environmental gradients interact to shape predation by Lycosidae in highly dynamic vegetable growing systems in China.RESULTSFor the sampled Lycosidae, crop identity, pesticide use, and seasons shape the abundance of preydetected in spider guts. For the taxonomic richness of prey, local- and landscape-scale factors gradients were more influential. Multivariate ordinations confirm that these crop-abundant spiders dynamically adjust their diet to reflect environmental constraints and seasonal availability to prey.CONCLUSIONThe plasticity in the diet composition is likely to account for the persistence of spiders in relatively ephemeral brassica crops. Our findings provide further insights into the optimization of habitat management for predator-based biological control practices.