Anastrepha fraterculus male enhancement with fruit supplement in the adult diet.

VERA, M. T.; RUIZ, M. J.; ABRAHAM, S.; OVIEDO, A.; WILLINK, E.

Valencia, España

Workshop; 3th RCM on Improving Sterile Male Performance in Fruit Fly SIT; 2008

In order to enhance Anastrepha fraterculus male performance in relation to SIT, the effect of supplementing adult diet with fruit was explored. Three series of experiments were performed. In the first, males were fed with grapefruit, with the conventional diet or with both all throughout the process of sexual maturation. In the second, males were fed with the conventional diet and then exposed to different fruit for 24 hours and confronted to females the day after. In the third, males were allowed to feed on fruit for different periods of time before exposing to females (1, 3, 5, 10 or 15 days). In the last two series of experiments, treated males were confronted to males fed with sugar and brewers yeast at a 3:1 ratio. The experiments were run in the laboratory with laboratory flies. We found that feeding or exposing the males to grapefruit did not resulted in an increase in male competitiveness. Males fed with grapefruit only had a lower performance than males fed with grapefruit and the conventional diet or males fed only with the conventional diet. When the evaluation was extended to different fruit, it was found that treated and untreated males had the same performance except for males exposed to lemon. Contrary to what was found in the other tephritid species, treated males had a lower performance. When males had access to the fruit for different periods, it was confirmed that males exposed to lemon for 24 hours had a lower performance compared to the unexposed males. This detrimental effect was reduced in males exposed for longer periods and there was a tendency of increased male competitiveness when the exposure time was 10 or 15 days. In the case of mango, there was no effect on males exposed for short periods (1, 3 or 5 days), a boosting effect on males exposed for 10 days, and a detrimental effect on males exposed for 15 days. The differences found among the different exposure times may reflect a need to metabolize toxic compounds or the need to ingest larger amounts of particular compounds. Given the fact that the preferred hosts in A. fraterculus are within the Mirtaceae family, as guavas, and citrus are considered non-hosts or poor hosts, it may be expected that males fed on guavas present some advantage. Ongoing efforts are now allocated to evaluate this fruit.