Beauveria bassiana (Ascomycota: Hypocreales)–treated Diamondback Moth (Lepidoptera: Plutellidae) Larvae Mediate the Preference and Functional Response of Euborellia annulipes (Dermaptera: Anisolabididae) Nymphs

Abstract

Biological control is one of the strategies to reduce populations of diamondback moth, Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae), the major pest of brassica. Entomopathogen-based biopesticides are recommended and used for its control, reducing the constant use of chemical pesticides. Predators and/or fungal entomopathogens have an increasing interest to be used against diamondback moth, and the compatibility of these control agents in the field is important for pest management. Here we experimentally investigate the effects of diamondback moth larvae treated with a biopesticidal formulation of Beauveria bassiana (Balsamo) Vuillemin in the feeding preference and functional response of the ring-legged earwig. We used untreated and B. bassiana-treated diamondback moth fourth instars (over a 24-h period of exposure) and Euborellia annulipes (Lucas) fifth instars. The nymphs were included in choice condition tests and different larval densities to the analysis of feeding preference and functional responses, respectively. Euborellia annulipes nymphs exhibited no feeding preference under choice conditions but presented different types of functional response: Type II on untreated and type III on fungus-treated diamondback moth larvae. The interaction between E. annulipes and B. bassiana observed in our study contributes to the understanding of the predator–prey–pathogen relationships with implications for P. xylostella integrated management strategies.

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

“…The type II response has been reported for E. annulipes that prey on lepidopteran pests. However, some authors have found that the functional response can change to type III depending on the temperature or whether the prey is infected by entomopathogenic fungi (Nunes, Dantas, et al, 2019; Nunes, Ramalho, et al, 2019; Nunes, Truzi, et al, 2019). Attack rate ( a ) and handling time ( h ), which determine the slope and height of a functional response curve, respectively (Holling, 1959), did not differ significantly between earwig males and females.…”

<i>Euborellia annulipes</i> Mortality and Predation on <i>Diatraea saccharalis</i> Eggs after Application of Chemical and Biological Insecticides

“…Other research has also shown that some synthetic chemical insecticides, such as spinosad, acetamiprid, and chlorpyrifos-ethyl, have no effects on the predation activity of earwigs [38], when the insects are exposed to a dose or concentration that isn't lethal [39]. On the other hand, infection by pathogens is a factor that affects predation in some insects [40] [41], however, according to [42],…”