The potential of entomopathogenic nematodes for the management of the mirid bugs Lygus rugulipennis (Poppuis), Liocoris tripustulatus (Fabricius) and Macrolophus pygmaeus (Rambur)

Mirid bugs (Hemiptera: Miridae) represent a significant challenge for greenhouse cash crops like cucumber, tomato and eggplants, leading to huge economic losses. This study investigated the potential of the entomopathogenic nematode (EPN) Steinernema carpocapsae as biological control agent of the mirid bug species Lygus rugulipennis, Liocoris tripustualtus, and Macrolophus pygmaeus through aerial spray application under laboratory and greenhouse conditions (only for L. rugulipennis and M. pygmaeus). The laboratory trials showed a significant effect of S. carpocapsae on the average survival rate of the three mirid species. The highest efficacy was found for subadults of L. rugulipennis (50%), followed by M. pygmaeus (25%) and L. tripustulatus (15%). Microscopic dissections showed that EPNs can infect all studied mirid species and life stages. Under greenhouse conditions, a significant difference was observed between developmental stages, with no significant effect for adults, but an efficacy of 19% and 32% for nymphs of L. rugulipennis and M. pygmaeus, respectively. These results highlight the potential of EPNs in the control of problematic mirid bugs in greenhouse vegetable production, which could lead to a reduction in the use of synthetic pesticides and promote more sustainable agricultural practices.