Attraction of Pest Insects, Neutral Insects and Natural Enemies to Coloured Sticky Traps in Vegetable Eco-Systems

Purpose: Sticky traps are effective for monitoring and managing insect pests. In addition to pest insects, beneficial insects are also caught in sticky traps. Hence, it is necessary to use traps to catch pest insects selectively. The attraction of different insect groups to coloured sticky traps was studied as an attempt to suppress the insect populations selectively in the field.

Research Method: Sticky traps: yellow, blue, luminous green, white, and transparent (control) were set in the field for 24 hours, and the insects caught in traps were collected and identified by their ecological role: pests, beneficial and neutral insects as well as the taxonomic group in relation to the trap colour.

Findings: Significant variation was found among the total numbers of insects attracted to different colour traps (χ2 =107 df=4 P<0.05). The highest number of insects was found in the luminous green trap (29.1%) followed by yellow (22.0%), white (18.8%), blue (17.9%), and transparent (12.2%). All colour traps attracted pest, beneficial and neutral insects. Data was inconsistent to specify trap colour to catch more pests and less beneficials. More dipterans (40.7%) were attracted to traps, and many of them were neutral. Blue-traps caught less number of neutral (29.1%) and beneficial insects (29.4%) compared with other coloured traps.

Originality/ Value: The behavioral response of different insect groups to colour was demonstrated. As sticky traps catch both beneficial and pest insects, sticky traps should be used under careful monitoring.