Feeding on yeast hydrolysate enhances attraction to cue‐lure in Queensland fruit flies,Bactrocera tryoni

Feeding on yeast hydrolysate (a source of nitrogen) has a strong influence on the physiology and behaviour of the Queensland fruit fly (Q‐fly), Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), affecting longevity, sexual maturation, oogenesis, and mating performance. In this study, we demonstrate that access to yeast hydrolysate also influences the development of attraction to cue‐lure in Q‐flies. We provided virgin Q‐flies various periods of access to yeast hydrolysate (continuous, 48 h, 24 h, or deprived). Attraction of males to cue‐lure was increased and occurred at an earlier age when they were fed yeast hydrolysate. Males given continuous access were strongly attracted to cue‐lure at a younger age (8 days after emergence), but by 12 days after emergence attraction of males given access to yeast hydrolysate for 48 h did not differ from males given continuous access. Attraction by males deprived or given just 24 h access to yeast hydrolysate was always significantly lower than those of males with continuous access. Male attraction to cue‐lure was highest in the early morning. While cue‐lure is most often thought of as a male attractant, virgin female Q‐flies were caught in cue‐lure traps at dusk at ages when they are known to be sexually mature. We suggest that cue‐lure or similar natural chemicals play a role in the Q‐fly mating system. γ‐Irradiation used to induce sterility had no significant effect on attraction to cue‐lure by Q‐flies.