Effect of gamma radiation on the male sterility and other quality parameters of peach fruit fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae)

Abstract

Mahmoud M.F., Barta M., 2011. Effect of gamma radiation on the male sterility and other quality parameters of peach fruit fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae). Hort. Sci. (Prague), 38: 54-62.Bactrocera zonata, a serious pest of fruits in many parts of the world, has recently been recorded in Northern Africa. Even though it has not been introduced to the European continent yet, a strong emphasis is being placed on developing effective measures to suppress this pest and to prevent it from establishing in neighbouring European countries. The sterile insect technique is widely used in integrated programmes against tephritid fruit flies and, in this paper, quality parameters of irradiated B. zonata were evaluated for possible use of sterile insect technique within the management of this pest. Pupae were irradiated ( 60 Co) 48 h before adult emergence (in an air atmosphere) with doses of 10, 30, 50, 70 or 90 Gy. While adult emergence and egg hatch decreased with increasing dose, no significant differences in female fecundity were found among doses. Exposure of pupae to 90 Gy resulted in a total sterility of eggs laid by non-treated females crossed with treated males. Only insignificant difference in the radiation effect on female fecundity was found. Moderate effects on sex ratio and size were recorded, as they decreased gradually by increasing doses. No considerable effect on flying capability was observed, but generally, the percentage of fliers decreased with increasing radiation doses. Fried's competitiveness values of treated males (30 and 70 Gy) suggest that irradiated males compete successfully with non-irradiated ones.

EFFECT OF GAMMA IRRADIATION ON THE QUALITY AND MATING COMPETITIVENES OF FRUIT FLIES Bactrocera dorsalis IN THE CAGE SCALE

“…The irradiation dose level did not affect egg production which is the result of mating between irradiated male and normal female fruit flies. Mahmoud & Barta (2011) reported the same thing for fruit flies B. zonata. Based on the results of testing the number of eggs, it is also known that the higher the radiation dose, the lower the number of eggs despite the slight difference.…”

“…Guerfali et al (2011) stated that the higher the irradiation dose, the lower the ability of sterile fruit flies to fly which will make the release of sterile fruit flies less effective. Mahmoud & Barta (2011) reported that the highest percentage of flying ability in fruit flies B. zonata occurred at the dose of 30 Gy, which was 67.5% and the lowest was at a dose of 90 Gy, which was 59.2%.…”

“…The lowest percentage of sex ratio occurred at a dose of 110 Gy, which was 44% (0.44). Mahmoud & Barta (2011) reported that the sex ratio tends to decrease gradually in line with the increasing of irradiation doses. Irradiation at the lowest dose of 10 Gy for B. zonata pupae produced the highest percentage of sex ratio which was 50% (0.50).…”

Dampak Iradiasi Sinar Gamma pada Produktivitas Aedes aegypti Jantan

“…Adapun penurunan daya tetas telur, dan kemunculan nyamuk pada F2 tidak menunjukkan penurunan yang signifikan bila dibandingkan dengan F1. pada lalat buah persik (Bactrocera zonata 15 Saunders).…”

Female mating failure and the failure of ‘mating’ in sterile insect programs

“…Thus, emphasis for mass-reared males should be made on producing large males. Whereas a standard diet during immature stages and controlled environmental conditions may yield mass-produced males with less size variation than wild males, factors such as larval crowding conditions (e.g., screwworm fly, Cochliomyia hominivorax Coquerel; Pitti et al, 2011) and irradiation [e.g., Bactrocera zonata (Saunders), Mahmoud & Barta, 2011], may decrease mass-reared adult or pupal size. Female preferences for sterile or wild males may fluctuate throughout the seasons, as sterile males may face greater competition in the field when environmental conditions produce large wild males (e.g., during cold months and or when high-quality food or hosts are available during immature stages; Navarro-Campos et al, 2011) than when smaller wild males are present.…”