Methoprene treatment reduces the pre-copulatory period in Anastrepha fraterculus (Diptera: Tephritidae) sterile males

D.F. SEGURA; M.E. UTGÉS; M.C. LIENDO; M.F. RODRÍGUEZ; F. DEVESCOVI; M.T. VERA; P.E.A. TEAL; J.L. CLADERA

JOURNAL OF APPLIED ENTOMOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2013 p. 19 - 29

0931-2048

Anastrepha fraterculus is a major fruit pest in South America. Ongoing studies encourage the implementation of the sterile insect technique (SIT) against this pest. Sexual readiness of sterile males is a key point for SIT. The pre-copulatory period of A. fraterculus males has not been reported before but it is expected to take several days. A reduction in reproductive development time was achieved in other Anastrepha after topical applications of juvenile hormone analogues, like methoprene. We studied methoprene application on the sexual maturation of A. fraterculus males. Methoprene effects on mating duration and sperm transfer was further evaluated, as well as acetone (methoprene solvent) effects on survival. Finally, we explored a method to deliver methoprene massively. Pheromone calling and mating ability were daily evaluated from adult emergence, and used as indicators of sexual maturity. A. fraterculus males showed a long precopulatory period (7days approximately), as other Anastrepha species. This process was accelerated after methoprene treatment (2.5ug/ul) both in non irradiated and irradiated males. Mating duration for methoprene treated males was longer than for mature untreated males, however no differences were detected between males in sperm transferred. Acetone did not affect survival. We found that dipping pupae in methoprene allowed the males to mature as fast as with the topical treatment. We conclude that the time required for A. fraterculus sterile males to become sexually mature can be shortened by the application of methoprene. This will effectively accelerate maturation with no detrimental effects on sperm transfer or survival. Dipping of pupae is a promising method to massively deliver methoprene and should be further investigated.