Unveiling the diet of predatory mites through DNA metabarcoding—can abiotic factors affect prey detectability?
Résumé
Despite the importance of predatory mites as biological control agents, the way that generalist species can maintain in agrosystems, the alternative prey they can feed on, the way they choose to eat one prey, or another are poorly known. For some phytoseiid predatory mite species, prey consumption has been characterized by lab tests (Cavalcante et al., 2015, 2017; Juan-Blasco et al., 2012; Oliveira et al., 2007). However, those approaches are sometimes difficult to perform, very time consuming and do not totally reflect interactions occurring in field conditions. New technologies that allow determining the diet of predatory mites in situ are highly desirable to supporting biological control programs. A promising avenue for deciphering the diet of predatory mites is offered by DNA metabarcoding. Although this approach has been used in the study of insects (Hosseini et al., 2008; Kaunisto et al., 2017; Paula et al., 2022), only starts to be applied to microarthropod biological control agents, as predatory mites (Navia et al., 2019). DNA metabarcoding was successfully applied to identify prey species of phytoseiid mites using group-specific primers. However, biotic and abiotic factors can affect the detectability of predatory mite preys through metabarcoding, as previously showed for studies using traditional molecular methods (=PCR Multiplex and Sanger sequencing) (Pérez-Sayas et al., 2015). This information is relevant to understanding the limits of using the methodology, to guide sample collection procedures, and to assure the correct interpretation of the results.