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Diamondback moth, Plutella xylostella, is considered the most important pest species of brassica crops and Euborellia annulipes can exhibit potential for its control. This work recorded the consumption of 4 th-instar larvae and pupae of P. xylostella by nymphs and adult females of the ring-legged earwig E. annulipes at different ages: 2, 4, 6, 8 and 10 days old. Nymphs in the 3 rd-instar and females of E. annulipes consumed daily more P. xylostella larvae than pupae. The consumption of diamondback moth pupae became constant as the 5 th-instar nymphs of the predator develop. In the other hand, the consumption of larvae decreases when nymphs are closer to molt. Female, regardless of its age, consumed more larvae than pupae of P. xylostella.

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Mortality of neonate larvae and eggs of Spodoptera frugiperda has an important contribution to the management of this pest. This work aimed to determine the development, quantify the consumption, the time of search and handling of eggs of S. frugiperda by Cereaochrysa cubana. The duration of development and the survival of C. cubana were determined using eggs of the alternative prey Anagasta kuehniella; eggs, newborn caterpillars and combined feeding of egg + newborn caterpillars of S. frugiperda. The daily and total consumption, the search and handling time were also evaluated, comparing eggs and caterpillars of S. frugiperda as prey. The duration of the larvae to adult phase of C. cubana was prolonged when the food was newborn caterpillars or eggs + newborn caterpillars of S. frugiperda (35.7 and 34.6 days) when compared to eggs of A. kuehniella and S. frugiperda (25.5 and 25.9 days). The predator's larvae showed a shorter larval and adult period when fed with eggs in relation to caterpillars. Larval viability of C. cubana was lower when fed with eggs + newborn caterpillars. Higher consumption and shorter search and handling time on newborn caterpillars of S. frugiperda, compared to prey eggs, are carried out by larvae of C. cubana during the third instar. Key words: biology; chrysopodes; fall armywormAspectos biológicos e comportamento da predação de Ceraeochrysa cubana sobre Spodoptera frugiperda RESUMO A mortalidade de ovos e larvas neonatas de Spodoptera frugiperda possui importante contribuição para o manejo desta praga. Este trabalho objetivou determinar o desenvolvimento, quantificar o consumo, o tempo de busca e de manipulação de ovos de S. frugiperda por Cereaochrysa cubana. A duração do desenvolvimento e a sobrevivência de C. cubana foram determinadas empregando-se ovos da presa alternativa Anagasta kuehniella; ovos, lagartas neonatas e alimentação combinada de ovos + lagartas neonatas de S. frugiperda. Também foram avaliados os consumos diário e total, o tempo de busca e de manipulação, comparando-se ovos e lagartas de S. frugiperda como presa. A duração da fase de larva a adulto de C. cubana foi prolongada quando o alimento foi lagartas neonatas ou ovos + lagartas neonatas de S. frugiperda (35,7 e 34,6 dias) comparado a ovos de A. kuehniella e S. frugiperda (25,5 e 25,9 dias). Larvas do predador apresentam menor período de larva-adulto quando alimentados com ovos em relação a lagartas. A viabilidade larval de C. cubana foi menor quando alimentadas com ovos + lagartas neonatas. O maior consumo e menor tempo de busca e de manipulação sobre lagartas neonatas de S. frugiperda, em comparação aos ovos da presa, são realizados por larvas de C. cubana durante o terceiro instar.

The diamondback moth (DBM), Plutella xylostella (L.) (Lepidoptera: Plutellidae), is the main pest of brassica crops worldwide. The ringlegged earwig, Euborellia annulipes (Lucas) (Dermaptera: Anisolabididae), has been reported as a potential predator of lepidopteran larvae, including this pest, and may therefore be used for biological control. Knowledge about predator-prey interactions is important to establish pest management strategies. Therefore, the objective of this work was to evaluate the influence of the developmental stage (larva and pupa) and density of P. xylostella on the preference and functional response of E. annulipes adult females. We used choice and no-choice tests to evaluate the foraging behavior and preference of E. annulipes on DBM life stages and varied prey density to assess the type of functional response of the ringlegged earwig. Larvae were preferred over pupae, and the predator's functional response was type II for both prey stages. Our results report the potential of E. annulipes as a biocontrol agent of P. xylostella. Understanding their interactions may help in decision-making and optimization of integrated management strategies.

The ring-legged earwig Euborellia annulipes has been studied as a natural enemy of pest-insects and a potential predator of diamondback moth. Temperature is an important factor that mediates the pest population density and may affect the predator-prey relationship dynamics. This study aimed to evaluate the effect of the temperature and development stage of Plutella xylostella individuals on the feeding preference of E. annulipes females. Three temperatures (18 ºC, 25 ºC and 32 ºC), two development stages (larvae and pupae) and two feeding conditions related to the prey capture (with or without choice) were assessed. No matter the temperature, ring-legged earwig females showed a preference for eating larvae, instead of pupae. The temperature and choice conditions influenced the amount of consumed preys, but only for larvae (not for pupae). The lowest larvae consumption was observed at 18 ºC, in both prey capture conditions.

This research aimed to evaluate the consumption of Hyadaphis foeniculi by Ceraeochrysa cubana larvae, based on the densities and developmental stages of the prey, as well as the predator searching and handling time, regarding its instar and previous feeding knowledge. In order to evaluate the predation rate, larvae of first, second and third instars of C. cubana were used, which were fed with aphids from first and second instars, from third and fourth instar, and from different instars, at three densities. For searching time and handling evaluation, green lacewing larvae were submitted to different feeding regimens: second instar larvae fed at the first instar with Anagasta kuehniella eggs; second instar larvae, fed at the first instar with H. foeniculi; third instar larvae, fed at the first and second instars with A. kuehniella eggs; third instar larvae, fed at the first instar with the eggs of A. kuehniella and at the second instar with H. foeniculi; third instar larvae, fed at the first and second instars with H. foeniculi. It can be concluded that the daily C. cubana predation rate is influenced by H. foeniculi densities and instars, but the predator searching and handling times are not influenced by the diets provided to them in their previous stages.

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.