Investigation on the effects of different wavelengths of the light on the Turkestan cockroach (Blatta lateralis) adults

Cockroaches may have an allergic effect on humans and carry various pathogenic organisms. In general, chemical substances (insecticides) such as sulfluramide, fipronil and imidacloprid are used to control cockroaches. However, insects can gain resistance against the chemicals used. In addition, these chemicals negatively affect human health and the environment. Therefore, new methods that can be used as an alternative to chemical insecticides used in cockroach control should be developed. Recently, especially with the production of LED bulbs, the use of lights in the control of harmful insects has increased. It has been found that rays of different wavelengths can have lethal, abducting or attracting effects against insects. The aim of this study is to develop a method which can replace the chemicals used against cockroaches, which is harmless to human health and environment. For this purpose, the effect of rays having different wavelengths (red, green, yellow, blue, white and dark) on Turkestan cockroach (Blatta lateralis) was investigated. In this study, adult cockroaches were exposed to three different light intensities (25, 250 and 2500 lux). The data obtained show that the sensitivity to the rays with different wavelengths may increase depending on light intensity. Especially, the orientation of adult cockroaches to the chamber where blue light with an intensity of 2500 lux was applied was at the lowest level of 0.89%. When the light intensity was reduced to 25 lux, the orientation to blue light increased to 9.52%. In general, the highest orientation was against the dark chamber in all trials. In addition, under all lux values, the orientation to red light was higher than green, yellow, blue and white light. As a result of this study, it has been determined that blue light may have an abusive effect on cockroaches and red light may be more attractive than other wavelengths.