Attached
Evidence for a male—produced sex pheromone and behavioral responses of male
and female Bacz‘rocera dorsal [s to the pheromone were investigated using a
horizontal wind tunnel under laboratory Conditions. Responses of males and
females to different combinations of live flies and male rectal glands were
assessed by monitoring three behavioral parameters namely the number of flies
performing upwind straight and zigzagging anemotactic flights over at least
50cm to the treatment, total number of flies landing on the treatment and the total
number of flies moved into the upwind section of the wind tunnel after 20
minutes. Significantly high female responses to live males were recorded in all
three parameters considered. Male responses to eithcr malcs or females were
considerably low. It is evident from the results that female B. dorsal is are
attracted to males and not vice versa. Neither of the sexes was attracted by their
own sex and the lack of responses of virgin males to virgin females can be
considered to be strong evidence for the absence of any female odour attracting
males. Female responses to male rectal glands were at their highest during the
‘dusk’ period. Behavioral responses of females observed in the wind tunnel allow
the conclusion to be drawn that the source of production or storage of the sex
pheromone in B. dorsal is males is the rectal gland. In addition, these results
confirm the previously reported observations that mating activity in this species
occurs only during the dusk period.
