BioControl (2009) 54, 341-350
Efrat Gavish-Regev, Ron Rotkopf, Yael Lubin and Moshe Coll (2009)
Consumption of aphids by spiders and the effect of additional prey: evidence from microcosm experiments
BioControl 54 (3), 341-350
Abstract: Spiders are common generalist predators in agroecosystems and have been suggested to lower herbivore abundance in crops. It is not clear, however, if spiders can effectively suppress pest populations, and if so, by what mechanisms. In a microcosm experiment, we examined the consumption of the bird cherry-oat aphid, Rhopalosiphum padi L. (Homoptera: Aphididae), a pest species in wheat fields, by three spider species that differ in their hunting methods. We then tested the effect of additional prey type on the ability of erigonid spiders to reduce aphids. In a 48-h experiment Mermessus denticulatus (Banks) (Araneae: Linyphiidae; Erigoninae) consumed more aphids than did Enoplognatha gemina Bosmans and Van Keer (Araneae: Theridiidae) and Bathyphantes cf. extricatus (O·P.-Cambridge) (Araneae: Linyphiidae; Linyphiinae). This difference may be due to the ability of erigonids to forage actively on the vegetation in addition to using their webs to catch prey. In a 7-week experiment, we provided springtails (Collembola) in high and low densities as additional prey to mated erigonids, prior to aphid introduction. Spiders in the low-density springtail treatment built more webs on the vegetation, and caused a 50% reduction in aphid populations. There were significantly fewer aphids in the low-density springtail treatment, but not in the high-density treatment, in comparison to the control (high-density springtails without spiders). The results suggest that additional prey density affects predatory interactions between M. denticulatus and R. padi and that erigonids, which occur in high densities in wheat fields in the Negev desert, may be involved in aphid suppression in these agroecosystems.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Efrat Gavish-Regev
Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution
environment/habitat manipulation
Pest and/or beneficial records:
| Beneficial | Pest/Disease/Weed | Crop/Product | Country | Quarant.
|
|---|---|---|---|---|
| Rhopalosiphum padi | Wheat (Triticum) | Israel | ||
| Mermessus denticulatus (predator) | Rhopalosiphum padi | Wheat (Triticum) | Israel | |
| Enoplognatha gemina (predator) | Rhopalosiphum padi | Wheat (Triticum) | Israel |
