CHEMISTRY AND BIOCHEMISTRY OF INSECT BEHAVIOR, PHYSIOLOGY AND ECOLOGY
Location: Chemistry Research Unit
Title: Methoprene modulates the effect of diet on male melon fly, Bactrocera cucurbitate, performance at mating aggregations
| Haq, Ihsan Ul - |
| Caceres, Carlos - |
| Henrrichs, Jorge - |
| Wornoayporn, - |
| Stauffer, Christian - |
| Robinson, Alan S. - |
Submitted to: Entomologia Experimentalis et Applicata
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 23, 2010
Publication Date: May 20, 2010
Citation: Haq, I., Caceres, C., Henrrichs, J., Teal, P.E., Wornoayporn, Stauffer, C., Robinson, A. 2010. Methoprene modulates the effect of diet on male melon fly, Bactrocera cucurbitate, performance at mating aggregations. Entomologia Experimentalis et Applicata. 136:21-30.
Interpretive Summary: The Melon fly is a quarantine pest of significant importance to a wide variety of orchard and vegetable crops. One way to control this pest is the sterile insect technique (SIT). Control is achieved in SIT by mass release of sterile males who mate with wild females. Wild females that mate with sterile males do not produce viable eggs which, over time, results in population decline and eradication. One of the more significant costs associated with SIT protocols for Tephritid flies is the need to hold mass reared adult flies for as many as 7, or more, days prior to release because males require time to become sexually mature. Scientist at the FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, Austria, Center for Medical, Agricultural, and Veterinary Entomology, USDA-ARS, Florida, and University of Natural Resources and Applied Life Sciences, Vienna have been studying if hormone therapy and protein dietary supplements can improve SIT. They have discovered that addition of the hormone mimic, methoprene, and a diet rich in protein accelerates reproductive development and optimizes reproductive success in males of the Mellon fly. The scientists are now developing methods to incorporate this technologies into mass rearing of sterile flies to improve efficacy of SIT.
The effect of dietary protein (P) and the topical application of juvenile hormone analogue (methoprene (M)) on mating behaviour of male melon fly, Bactrocera cucurbitae, was assessed in the laboratory and in field cages. Age, dietary protein and methoprene application improved the sexual success and copulation behaviour. Treatment with methoprene (M+) to protein-deprived (P-) males had only a slight effect on the acceleration of sexual maturity, but application of methoprene (M+) to protein-fed (P+) males greatly accelerated sexual maturity. Protein diet (P+) increased mating success of males in comparison to protein-deprived (P-) males. Protein and methoprene have a synergistic effect on sexual signaling in males; such M+P+ males courted more vigorously, at an earlier age and had a higher courtship rate than methoprene and/or protein-deprived males. Copulation duration was correlated with nutritional status and M+P+ males copulated longer at the age of induced sexual maturity than M-P+ males. These results confirm that in this species with a lek mating system, females discriminate between the males based on their sexual signals, which were improved by protein, methoprene and age. The results are discussed in the light of questions regarding female choice for direct or indirect benefits that the female may gain by discriminating amongst the males in a lek. The results also have implications for improving the efficiency of the Sterile Insect Technique for this species.