Evaluation of Predation on Phytophagous Insects by a Phytozoophagous Mirid Bug, Apolygus lucorum

Apolygus lucorum, a phytozoophagous mirid bug, plays an important role in the species interactions within fruit tree and cotton ecosystems. Previous research has mainly focused on the phytophagous damage that it causes to crops, while its role as a predator of arthropods remains poorly understood. In this study, we systematically investigated the functional responses of A. lucorum to three crop pests: eggs of Helicoverpa armigera, nymphs of Aphis gossypii, and nymphs of Bemisia tabaci. The results show that the predatory behavior of A. lucorum towards all three prey species followed a Holling type II functional response model. Predatory performance varied significantly depending on prey species, developmental stage, and sex of the mirid. The theoretical maximum predation rate was highest for A. gossypii (833.33 individuals/day) and lowest for B. tabaci nymphs. Adult mirids and older nymphs (4th instar) exhibited higher predation rates than younger nymphs. Field-collected A. lucorum from Bt cotton fields were analyzed using molecular diagnostics, and the result confirmed natural predation on A. gossypii, which was consistent with observed pest occurrence patterns in the field. Overall, this study clarifies the prey selectivity and stage-dependent predatory strategies of A. lucorum, providing insights into its trophic flexibility as a facultative predator. These findings contribute to a more comprehensive understanding of its ecological role in agricultural ecosystems, but do not support its use as a biological control agent given its predominantly phytophagous nature and documented pest status.