Male diet and age influence to inhibit female remating in Ceratitis capitata (Diptera: Tephritidae)

This study evaluated the influence of age and adult nutritional status of Ceratitis capitata males on their ability to inhibit female remating. Their roles and that of copula duration on the amount of sperm transferred to female spermathecae were also analysed. After emergence, adults were kept in separate groups according to their diets (either high protein 6.5 g of brewers yeast, or low protein 3.5 g of brewers yeast) and their age at the time of use in experiments (4, 8, 12, 16 and 20 days old). The results demonstrated that: (i) male age was not a factor that influenced remating when females mated with well-nourished males; however, the youngest males (4 days old) in the low-protein group were less efficient in preventing female remating; (ii) 12- and 16-day-old males fed on a high-protein diet transferred and produced more sperm than males of other groups; (iii) there was no correlation between copula duration and the amount of sperm transferred to the female; the longest copula durations were observed among low-protein-diet/20-day-old males. These results suggest that age and nutrition influence the ability of the males to inhibit female remating. The sterile insect technique is most effective when females do not remate after coupling with sterile males, and therefore, the capacity to inhibit female remating is an important characteristic of males released in the field.