Ecological Entomology (2017) 42, 235-244
Claire Detrain, Melanie Fichaux and François Verheggen (2017)
Tuned protection of aphids by ants against a predatory hoverfly
Ecological Entomology 42 (3), 235-244
Abstract: 1. Aphid-tending ants that feed on honeydew have evolved strategies against aphidophagous insects and tune their aggressive behaviour according to the level of danger for their trophobionts. Here we investigate how Lasius niger Linnaeus (Hymenoptera: Formicidae) ants react to different instars of Episyrphus balteatus De Geer (Diptera: Syrphidae) hoverflies which vary in their voracity and defensive abilities.
2. During pairwise encounters, early syrphid instars (eggs, L1, and L2 larvae) elicited lower aggression scores compared to third larval instars (L3), which was intensively bitten by ants. L3 tried to escape from ants by releasing a sticky and toxic secretion over biting ants that died or underwent severe morbidity.
3. In a standardised system including the host plant, aphid, tending ant, and hoverfly, the ability of ants to protect an Aphis fabae Scopoli (Hemiptera: Aphididae) colony was evaluated. Early E. balteatus instars placed onto the plant elicited no mobilisation of ants, which often removed the hoverfly successfully. Eggs and early instars appeared as the weak links for integrated pest management by hoverfly auxiliaries.
4. In contrast, L3 induced the number of ant patrollers to increase at a local scale without any further recruitment from inside the ant nest. L3 syrphids were quite efficient at gluing ants with defensive secretions and at resisting to removal attempts by ants.
5. While supporting the assumption that ants tune their defensive response to the aphidophagous predator, the present results also showed a lack of efficient protection of their trophobionts from the most voracious late syrphid instar.
(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): François J. Verheggen
Research topic(s) for pests/diseases/weeds:
environment - cropping system/rotation
Research topic(s) for beneficials or antagonists:
environment/habitat manipulation
Pest and/or beneficial records:
| Beneficial | Pest/Disease/Weed | Crop/Product | Country | Quarant.
|
|---|---|---|---|---|
| Aphis fabae | ||||
| Lasius niger | ||||
| Episyrphus balteatus (predator) | Aphis fabae |
