Use of attract-and-kill stations on mushroom farms to kill mushroom flies

Mushroom flies, including the mushroom phorid fly, Megaselia halterata, and the fungus gnat Lycoriella ingenua, reduce mushroom quality and yields through feeding on the actively growing mycelium and via transmission of pathogenic green mold (Trichoderma agressivum). M. halterata infestations also plague local communities in the areas surrounding mushroom farms. We developed and tested novel control methods on mushroom farms to control mushroom fly populations from 2019-2021. Our methods consist of attract-and-kill stations that target key behaviors in the life cycle of both species of flies. The first farm to employ this strategy in 2020 reported that M. halterata populations on the farm were reduced by 99.99% after one full growing cycle had been completed. Most notably, mushroom yields increased by 25.66% during the study and are expected to increase further now that fly populations have been reduced to nearly zero on this farm. The farm managers were able to extend the cropping cycle from two mushroom harvests per room to three or even four harvests per room and observed significant increases in mushroom quality. Field studies performed at 17 farm sites in 2021 showed farms using our novel attract-and-kill stations had significantly reduced fly populations compared to farms not using the methods. Importantly, these field studies were performed from August to December, when mushroom phorid fly populations are at their seasonal peak.