Parasitism-mediated prey selectivity in laboratory conditions and implications for biological control

Author(s)

Moral, Rafael de Andrade ; Borges Demetrio, Clarice Garcia ; Hinde, John ; Conde Godoy, Wesley Augusto ; Fernandes, Francisco Sales

• Document type: Journal article
• Source: BASIC AND APPLIED ECOLOGY; v. 19, p. 67-75, MAR 2017.
• Web of Science Citations: 4

Abstract

In agroecosystems, parasitoids and predators may exert top-down regulation and predators for different reasons may avoid or give preference to parasitised prey, i.e., become an intraguild predator. The success of pest suppression with multiple natural enemies depends essentially on predatorprey dynamics and how this is affected by the interplay between predation and parasitism. We conducted a simple laboratory experiment to test whether predators distinguished parasitised prey from non-parasitised prey and to study how parasitism influenced predation. We used a host-parasitoid system, Spodoptera frugiperda and one of its generalist parasitoids, Campoletis flavicincta, and included two predators, the stinkbug Podisus nigrispinus and the earwig Euborellia annulipes. In the experiment, predators were offered a choice between non-parasitised and parasitised larvae. We observed how long it took for the predator to attack a larva, which prey was attacked first, and whether predators opted to consume the other prey after their initial attack. Our results suggest that, in general, female predators are less selective than males and predators are more likely to consume non-parasitised prey with this likelihood being directly proportional to the time taken until the first prey attack. We used statistical models to show that males opted to consume the other prey with a significantly higher probability if they attacked a parasitised larva first, while females did so with the same probability irrespective of which one they attacked first. These results highlight the importance of studies on predatorparasitoid interactions, as well as on coexistence mechanisms in agroecosystems. When parasitism mediates predator choice so that intraguild predation is avoided, natural enemy populations may be larger, thus increasing the probability of more successful biological control. (C) 2016 Gesellschaft fur Okologie. Published by Elsevier GmbH. All rights reserved. (AU)

• FAPESP's process: 11/15253-6 - Statistical and ecological modeling of trophic relations among pests and natural enemies
• Grantee: Rafael de Andrade Moral
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 14/12903-8 - A toolbox for entomological data modelling
• Grantee: Rafael de Andrade Moral
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate