Outcrossing and the Mating Competitiveness of Male Mediterranean Fruit Flies (Diptera: Tephritidae): Results from the World’s Oldest Mass-Reared Strain

The Hawaiian HI-LAB strain is the oldest mass-reared strain of Mediterranean fruit fly, Ceratitis capitata (Wied.), in the world, and recent laboratory and field data show that HI-LAB males perform poorly in mating competition against wild males. The purpose of this study was to determine whether the mating performance of HILAB males could be improved by a single outcrossing event with wild flies (HI-LAB females X wild males). Using field-caged host trees, I monitored male mating success with wild females and found that (1) HI-LAB males had low mating success relative to wild males, (2) F 1 hybrid males mated with equal frequency as wild males, and (3) F 10 hybrid males had a reduced mating success similar to that recorded for the HI-LAB males. The implications of the present findings for mass-rearing strategies are discussed.