Light traps for managing the coconut black headed caterpillar

Moths of Opisina arenosella, the major defoliator of coconut palms in India and Sri Lanka, are known to be phototropic. However, this feature has not been exploited in managing the pestiferous populations of Opisina. Therefore, the present study aimed at designing and evaluating suitable light traps, which could be integrated with the current scheme of pest management. Four types of traps-bucket trap, modified bucket trap, tray-water trap and trench trap, were evaluated. Results showed the tray-water trap to be the most efficient. Using this trap four light sources (halogen bulb, CFL lamp, petromax and mercury vapour lamp) at two different heights (ground level and 3′ above ground level) were further evaluated. It was found that the tray-water trap placed at 3′ above ground with a halogen bulb facing upwards was the best combination for trapping moths of Opisina. It appears that there is enough potential to include light trapping of moths as one of the components of IPM of Opisina.