Abstract
Ceratitis capitata (Mediterranean fruit fly) is a globally significant pest causing major yield losses and trade restrictions in fruit production. Although native entomopathogenic nematodes (EPNs) from South African soils offer potential for sustainable pest control, their efficacy against C. capitata remains poorly understood. This study evaluated two indigenous EPN isolates, Steinernema jeffreyense and Heterorhabditis bacteriophora, against larval and pupal stages of C. capitata under laboratory conditions. Larvae were exposed to 0, 25, 50, 75, and 100 IJs/50 µL, while pupae received 0, 100, 150, 200, and 250 IJs/50 µL. Both trials used 2 × 5 factorial designs with five replications and were repeated twice. Data were analyzed using two-way ANOVA in Statistix 10, with means separated by Tukey’s HSD test (α = 0.05). Variables measured included mortality, mortality speed, infectivity, and pupation rate. No significant interaction between EPN species and concentration was observed in the larval trial, whereas the pupal trial showed highly significant interactions for all variables. Both species caused concentration-dependent mortality, with H. bacteriophora consistently outperforming S. jeffreyense. Interestingly, the highest larval mortality occurred at the lowest concentration tested (25 IJs), while significant pupal mortality was only achieved at the highest concentration (250 IJs). These findings demonstrate that H. bacteriophora and S. jeffreyense are promising biological control candidates against C. capitata. However, field validation, assessment of nematode persistence across soil types, and formulation improvements are necessary to translate these laboratory results into practical, sustainable fruit fly management strategies.
Biography
Carol Shabalala is an MSc candidate in Entomology at the University of Mpumalanga. She holds a BSc Honours degree, and her research focuses on native entomopathogenic nematodes for sustainable fruit fly management. She attended a nematode short course at Stellenbosch University (2025) and has presented at the One Health International Conference (Bucharest) and the Sustainability Symposium (UMP, 2026). She was an exhibitor at the Penreach STEAM Festival 2026 in Mbombela and tutors all Entomology modules at UMP.
