SCREENING ENTOMOPATHOGENIC NEMATODES FOR THEIR POTENTIAL AGAINST DROSOPHILA MELANOGASTER

Fruit flies are among the most destructive insect pests affecting horticultural crops globally. They cause significant losses in fruit and vegetable production by reducing both quality and yield. In a series of laboratory experiments conducted in the Khyber Pakhtunkhwa Province of Pakistan, the infectivity of six entomopathogenic nematode (EPN) species—Steinernema carpocapsae, S. feltiae, S. kraussei, S. glaseri, Heterorhabditis indica, and H. bacteriophora—was evaluated against the fruit fly Drosophila melanogaster. Following exposure, the larvae were dissected to detect the presence of nematodes. Among the tested species, H. bacteriophora and S. feltiae demonstrated the highest infection rates, with 97.6% and 85.1% respectively, indicating their strong potential as biological control agents. In contrast, S. glaseri was found to be the least effective against D. melanogaster. Based on adult fly emergence data, H. bacteriophora and S. feltiae were identified as the most virulent EPNs. The study also suggested that measuring adult fly emergence is a more reliable method for assessing EPN efficacy than larval dissection. Infections in the pupal stage were comparatively lower, with S. feltiae and H. indica causing 60% and 58% infection rates, respectively. These findings suggest that D. melanogaster is susceptible to infection by H. bacteriophora and S. feltiae, highlighting their potential role as key components in integrated pest management (IPM) strategies for controlling fruit fly populations.