Effect of several factors on the phototactic response of the oriental armyworm, Mythimna separata (Lepidoptera: Noctuidae)

Recently, light traps equipped with light-emitting diode (LED) lights have been used to monitor and control nocturnal insect pests. The oriental armyworm, Mythimna separata Walker, is an important cosmopolitan agriculture pest. The phototactic responses of nocturnal insects, including moths are influenced by abiotic and biological factors. The present study aimed to evaluate the phototactic response to different wavelength LED lights to determine the wavelength to which M. separata adults are most sensitive, and then identify the effects of several factors on the phototactic response. Our experiments revealed that M. separata adult moths had a significantly higher attraction rate to the green (520?nm) LED light compared with other LED lights, the green LED light was 1.28 times more attractive the moths than the commercial double-wave light used as a control. The phototactic response of the adult moths was significantly influenced by several factors, including adaption time in darkness, age, mating status and sexuality. These findings suggest that using a green LED light as a light source in trap could be effective in monitoring or controlling M. separata moths. Our results may provide a theoretical and scientific basis for improving the light trap technique for M. separata moths.