Bulletin of Entomological Research (2010) 100, 367-371

O.L. Kvedaras, M. An, Y.S. Choi and G.M. Gurr (2010)
Silicon enhances natural enemy attraction and biological control through induced plant defences
Bulletin of Entomological Research 100 (3), 367-371
Abstract: Silicon (Si) is known to have a role in constitutive plant defence against arthropod pests, and recent work has illustrated involvement in induced plant defences. The present tri-trophic study tested the hypothesis that Si increases natural enemy attraction to pest-infested plants and improves biological control. Cucumber plants treated with potassium silicate (Si⁺) and untreated control plants (Si^-) were maintained in separately vented glasshouse compartments. Y-tube olfactometer studies showed that adult Dicranolaius bellulus were significantly more attracted to Si⁺ plants upon which Helicoverpa armigera larvae had fed compared with Si^-, pest-infested plants. Predators were not significantly more attracted to Si⁺ plants when comparing uninfested cucumbers. In a field experiment, we placed H. armigera-infested and uninfested Si⁺ and Si^- cucumber plants in a lucerne stand. Removal rates of H. armigera egg baits showed predation was greater for Si⁺ infested plants than for other treatments. Results suggest that Si applied to plants with a subsequent pest infestation increases the plants' attractiveness to natural enemies; an effect that was reflected in elevated biological control in the field.
(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): Olivia L Reynolds, Geoff M. Gurr

Research topic(s) for pests/diseases/weeds:
resistance/tolerance/defence of host
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
environment/habitat manipulation

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Helicoverpa armigera	Cucumber (Cucumis sativus)
Dicranolaius bellulus (predator)	Helicoverpa armigera	Cucumber (Cucumis sativus)