Researchers tested seventeen types of fungi that infect insects to see if they could control the olive fruit fly, a major pest in Greece that damages olive crops. Using fungi from local Greek soil samples, they exposed young olive fruit flies to different fungal treatments both in soil and without soil. Some fungi, particularly Aspergillus flavus and Aspergillus keveii, were highly effective at killing the flies and preventing them from reproducing normally. These results suggest that using these naturally occurring fungi could be a safer alternative to chemical pesticides for protecting olive groves.