Exposure to guava increases male sexual competitiveness in the South American fruit fly, Anastrepha fraterculus.

RUIZ, M. J., A. OVIEDO, S. ABRAHAM, M. MENDOZA, D. F. SEGURA, N. A. KOULOUSSIS, E. WILLINK AND M. T. VERA

Mazatlán, Sinaloa, México

Congreso; 7a. Reunión del Grupo de Trabajo en Moscas de la Fruta del Hemisferio Occidental.; 2008

Exposure to plants has been shown to influence sexual behavior in a number of phytophagous insect species. Here we examined the effect of fruit exposure on the mating competitiveness of male Anastrepha fraterculus, by evaluating six fruit types, different durations of exposure and the need of physical contact with the fruit. In grapefruit, lemon, and orange males were exposed to essential oils emanating from glands in the flavedo area, whereas mango, papaya and guava were cut in halves so that males had access to the pulp. To run a test ten treated males, ten unexposed control males, and ten females were placed in plexiglass cages and the number of couples obtained for each male type was monitored for two hours. Results showed that exposure to guava increased sexual performance, whereas exposure to lemon and grapefruit decreased it. Different exposures of 1, 5, 10 or 15 days to mango had no effect on male competitiveness, whereas in lemon exposures longer than one day eliminated the detrimental impact on mating competitiveness. The duration of exposure on guavas had also an effect, but this varied between replicates and two categories of males used (wild and laboratory). Mating advantage did not require physical contact with guava and the possible ingestion of fruit compounds, since plain exposure to volatiles ensured the effect on mating competitiveness. The possibility of implementing guavas to enhance A. fraterculus male sexual competitiveness in control operations and the potential role of the compound a-copane are discussed.