Suppression of activity and compound eye spectral sensitivity of two noctuid moths, helicoverpa armigera and mamestra brassicae under flickering green light

Abstract

In order to develop an economical pest-control lighting system for two noctuid species, Helicoverpa armigera and Mamestra brassicae, we investigated the daily activity of these two species with illumination at night. The compound eye spectral sensitivity of the two moths showed peaks at 360nm and 500-550nm. We selected green LED peaking at 535nm for the lighting device, because this wavelength has little effect for plants. The light intensity was 2.5×1017 photons·m-2·s-1 at a distance of 10cm from the light source. We recorded the activities of moths using an actograph, and compared the activities at night with and without the green illumination. Continuous illumination at night reduced the activities most effectively in both species. While a 0.2Hz flickering condition 0.5sec ON and 4.5sec OFF significantly suppressed the activity in H. armigera, no significant effect of flickering light was detected in M. brassicae.