Secondary predation by omnivores: Cereal aphid consumption bears no risk of misinterpretation in <scp>DNA</scp> ‐based diet analysis

Many omnivorous arthropods act as important pest control agents in agroecosystems. Assessing their prey choices helps to better understand biocontrol potential different environmental settings. To this end, multi-target approaches of molecular gut content analysis allow studying choices. Yet, DNA-based trophic interactions is challenged by the question whether detected food DNA was ingested primarily direct prey, or secondarily via a consumed animal. Experimental data are needed bias derived through secondary predation. Here we address issue for phloem-feeding aphid carabids. In feeding experiments, Pseudoophonus rufipes beetles were offered grain aphids Sitobion avenae primary which had fed on barley seedlings. Gut samples carabids collected after 0, 3, 9, 12, 24, 32 64 h digestion time and whole-body screened presence plant DNA. Samples positive subsequently tested with Poaceae-specific primers. None 7.8% that general amplified Poaceae Moreover, none extracted DNA, neither nor family-specific We, therefore, conclude detections our experiment can be ascribed remnants material guts field-collected Our findings demonstrate these an unlikely cause false link assignment because no either from host-plant bodies, could carabid samples.