Sex Pheromone Studies on Sweet Potato Weevil, Cylas formicarius (Fabricius)

Sex pheromone studies based on trap catches conducted over 24 h at two hourly interval during two seasons indicated that maximum trap catches were obtained during evening hours (16–18 h). Male captures were highest in the traps installed at canopy level and lowest in the traps erected at four feet and above the ground level. Traps erected at 1, 2, 3, 5 and 10 m away from the weevil infested field clearly showed that as the distance increased from 1 to 10 m from the infested field the weevil captures progressively decreased in the pheromone traps. Pheromone traps erected at 10 m distance between the traps recorded higher catches compared to traps installed at 5, 15, 20 and 25 m. Synthetic septa kept in pheromone traps trapped more weevils compared to traps where the septa was replaced with virgin females. Sweet potato tubers kept in place of septa attracted female weevils.