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

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 predator-prey 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 nonparasitised 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 predator-parasitoid 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. Zusammenfassung In Agrarökosystemen können Parasitoide und Prädatoren 'top-down'-Kontrolle ausüben. Aus unterschiedlichen Gründen können Prädatoren parasitierte Beutetiere meiden oder präferieren. Der Erfolg der Schädlingskontrolle mit mehreren Antagonisten hängt entscheidend von der Räuber-Beute-Dynamik ab und davon, wie diese vom Wechselspiel zwischen Prädation und Parasitismus beeinflusst wird. Wir führten ein einfaches Laborexperiment durch, um zu prüfen, ob Räuber zwischen parasitierten und nicht parasitierten Beutetieren unterschieden und um zu untersuchen, wie Parasitierung die Prädation beeinflusste.

Literature Review on the Natural Enemies of Spodoptera Frugiperda J. E. Smith (Lepidoptera: Noctuidae) and the Effectiveness of Their Use in the Management of This Pest in Corn (Zea Mays L.)

“…and T. pretiosum of S. frigiperda. [43] showed the effectiveness of the predator-parasitoid symbiosis in controlling the caterpillar in Brazil under laboratory conditions. In Florida, [44] showed the effectiveness of the association of P. maculiventris, E. floridanus and C. marginiventris in Literature Review on the Natural Enemies of Spodoptera Frugiperda J. E. Smith (Lepidoptera: Noctuidae) and the Effectiveness of Their Use in the Management of This Pest in Corn (Zea Mays L.) the integrated management of S. frugiperda and the conditions for a better use of these natural enemies.…”

Life stage and population density of Plutella xylostella affect the predation behavior of Euborellia annulipes

“…In each container, we kept on average 40 nymphs. For this research, we chose to use only adult females as they are more aggressive predators than males (Moral et al, 2017). Sex dimorphism can be distinguished from the difference of the forceps (male presents the right branch of the forceps turning sharply inward near the tip, and in the female, the forceps are slightly and equally curved at the tips) (Klostermeyer, 1942).…”

“…Sex dimorphism can be distinguished from the difference of the forceps (male presents the right branch of the forceps turning sharply inward near the tip, and in the female, the forceps are slightly and equally curved at the tips) (Klostermeyer, 1942). For this research, we chose to use only adult females as they are more aggressive predators than males (Moral et al, 2017).…”

“…Earwigs were found to be predators in cruciferous crops, such as cabbage in The Philippines (Basedow, 1993) and collard greens in Brazil (Ribeiro & Gontijo, 2017). The ringlegged earwig, Euborellia annulipes (Lucas) (Dermaptera: Anisolabididae), is considered to be one of the most cosmopolitan species (Kocarek et al, 2015) and, although it is omnivorous, some researchers have reported this insect as a predator of lepidopteran pests, such as Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae) and P. xylostella (Silva et al, 2009;Moral et al, 2017;Nunes et al, 2018). However, there are few studies evaluating the predation behavior of E. annulipes and its effect on economically important insect pests.…”

Predation potential of the earwig Euborellia annulipes on fruit fly larvae and trophic interactions with the parasitoid Diachasmimorpha longicaudata

“…Earwigs usually enter fallen fruits through openings, where they may find non‐parasitized and parasitized fruit fly larvae in the same fruit. Previous studies have shown that the ability of E. annulipes to discriminate between non‐parasitized and parasitized prey varies depending on the sex of the earwig and on the particular host‐parasitoid system (Moral, Demetrio, et al, 2017; Nunes, Ramalho, et al, 2019). For application in biological control, it is important to understand trophic interactions between predators and parasitoids where they coexist and target the same prey/host species (Frago, 2016; Moral, Demetrio, et al, 2017).…”