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Behaviour-modifying chemicals like pheromones and kairomones hold a great potential in pest management. Evidences from mating behaviour studies of the banana weevil, and from the weevil's responses to their freeze-killed conspecifics, body washes/extracts, live conspecifics (olfactometer studies), and trapped volatiles of mature and immature adults clearly suggest that two types of pheromones are produced in this insect: a female produced sex pheromone and a male produced aggregation pheromone. Both are perceived by olfactory means. The latter has already been isolated by earlier workers and is in use in control programs. Greater successes may however, be recorded with the control of this pest (e.g. in mating disruptions, mass trappings, pest monitoring) if the female-sex pheromone also gets finally isolated, and used in conjunction with good cultural practices.

The banana weevil, Cosmopolites sordidus Germar mates repeatedly in its lifetime. No elaborate courtship behavior was seen before mating in the laboratory. However, 'sniffing' (an activity by which male weevils used their antennae to contact the abdominal tip of the female, as if to perceive some stimulus), often preceded mating. This observation may be an indication of a chemical pheromone involved in the mating behaviour of this insect. Male banana weevils generally displayed aggressive mating behaviour. Matings occurred under both light and dark conditions, but significantly more in the dark. A direct and positive linear correlation was observed between mating and sniffing under both light and dark conditions. Similar trends or correlations were observed between mating and mating duration; mating and sniffing durations respectively.

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