LAUSR

The selection of suitable food resources for parasitoids plays an important role in their effectiveness as biological control agents. We investigated how different diets influence resource allocation in two Tephritidae fruit fly parasitoids, Fopius arisanus and F. caudatus. The diets consisted of pollen from cotton Gossypium hirsutum, coatbutton Tridax procumbens and maize Zea mays, a mixture of pollen with honey, and honey alone. Longevity, parasitism, lifetime fertility and life table parameters such as net reproductive rate (Rο), intrinsic rate of increase (rm), finite rate of increase (λ) and mean generation time (Tc) were assessed. Our findings show that the two Braconidae species consumed pollen with a preference of coatbotton and cotton pollen. Host‐deprived F. arisanus with access to cotton and maize pollen mixed with honey exhibited increased longevity by 14% and 27%, respectively, compared to honey alone. However, when host eggs were available, the addition of pollen did not affect F. arisanus longevity, mortality risk, as well as parasitoids emergence compared to honey alone. The addition of coatbutton and maize pollen to honey resulted in higher fecundity, parasitism and superparasitism in F. arisanus. Furthermore, maize pollen mixed with honey led to a higher proportion of female offspring and an increased net reproductive rate (R₀) in F. arisanus compared to other diet treatments. In F. caudatus, adding maize pollen to honey decreased longevity compared to honey alone, while other pollen types showed no significant effect. Our findings highlight the importance of assessing plant pollen suitability before implementing plant‐derived nutritional supplements in mass‐rearing or conservation biological control.