Environmental Entomology (1972) 1, 490-497

A.P. Economopoulos (1972)
Sexual competitiveness of gamma-ray sterilized males of Dacus oleae. Mating frequency of artificially reared and wild females
Environmental Entomology 1 (4), 490-497
Abstract: Wild olive fruit flies Dacus oleae (Gmelin), reared in the laboratory on olive fruits (W), and flies reared on artificial diet (AD) were mixed in various strain and sex ratios as soon as they were sexually mature. In some experiments the AD males were sterilized by ⁶⁰Co gamma-radiation. They received 8 krad either as advanced pupae or as young adults.
Longevity was practically the same for normal W and AD flies of both sexes and for males irradiated at the adult stage, but was slightly decreased in males irradiated at the pupal stage. Most of the observed matings were recorded during the last hour of artificial twilight at the end of the photophase. The intermating period (derived from the number of matings with either W or AD males at the time of maximum mating activity) of W females was much shorter than that of AD females. On the average, 6-10 days (W females) and 12-18 days (AD females) were needed for a new mating during the 1st 35 experimental days. Intermating periods were much longer as flies grew older.
When normal W and AD males competed for W females, they were nearly equal, but AD males irradiated at the pupal stage were fully competitive only during the Ist week. Subsequently, they were less active than W males by a factor of 3 to 4 or even more. Egg hatch was markedly reduced only during the 1st 4 weeks. When AD males were irradiated as adults their competitiveness improved strikingly, approaching that of normal males. Egg hatch remained low according to the ratio of males throughout the experiment.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): Aristidis P. Economopoulos

Research topic(s) for pests/diseases/weeds:
control - general
rearing/culturing/mass production

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Bactrocera oleae	Olive (Olea europaea)	Greece