The Roles of Mating, Age, and Diet in Starvation Resistance in Bactrocera oleae (Olive Fruit Fly)

SIMPLE SUMMARY: The olive fruit fly (Bactrocera oleae (Rossi) (Diptera: Tephritidae)) is a pest of major economic importance that threatens the olive industry. Studying several factors affecting the survival ability of this insect during food deprivation, such as its mating status, age, and diet, may provide important insights into the biology of B. oleae that are useful for its effective control. The starvation resistance (hours of survival after the removal of food) of adult olive fruit flies was measured in four age classes in virgin and mated adults fed a full diet (water/sugar/yeast hydrolysate as protein in a 5:4:1 ratio) or a restricted, sugar-based diet lacking in protein, examining both males and females. The pattern of starvation resistance was the same for both genders under the same conditions (mating status, age, and diet) in the laboratory. Specifically, (a) mated adults showed much less resistance to starvation compared to virgin adults; (b) younger adults endured longer starvation periods compared to older adults; and (c) adults fed the restricted diet endured longer starvation periods than those fed the full diet. We conclude that mating, a full diet, and aging reduce starvation resistance. ABSTRACT: The olive fruit fly (Bactrocera oleae (Rossi) (Diptera: Tephritidae)), although a pest of major economic importance for the olive industry, has not been sufficiently studied with respect to the factors affecting its survival resistance to food deprivation. In the present study, we examined the effect of the interaction between mating status (virgin/mated), age class (11–20/21–30/31–40/41–50), and diet quality (protein plus sugar or only sugar) on starvation resistance in B. oleae under constant laboratory conditions. We conducted a total of 16 treatments (2 × 4 × 2 = 16) for each gender. Our results showed that starvation resistance in B. oleae did not differ significantly between females and males. The main conclusions of our study regarding mating status, age, and diet indicated that mated adults showed much less starvation resistance compared to virgins, younger adults endured longer, and the adults fed a restricted diet endured longer than those fed a full diet. A three-way interaction between mating status, diet, and age class was also identified and was the same for both genders. The interaction between mating status, age class, and diet also had a significant influence on starvation resistance in both sexes.