Orientation Behavior and Regulatory Gene Expression Profiles in Migratory Agrotis ipsilon (Lepidoptera: Noctuidae)

Many insects such as the crop pest Agrotis ipsilon (black cutworm) migrate seasonally to exploit suitable breeding and winter habitats. The migration of a crop pest also increases the risk of sudden outbreaks. Knowledge about insect migration thus is important for developing a forecasting and warning system for migratory pests. Here we used directional flight devices to study the orientation behavior of A. ipsilon in China during the northward and southward migratory periods and showed that the insects during each period exhibited a common cardinal orientation. Northward migratory moths were oriented at an orientation angle mean of 24.4 degrees and the southward at 205.17 degrees. Expression levels of cryptochrome and magnetoreceptor genes in migratory populations were higher than in a reared population and higher in the southward migratory population than in the northward. These findings provide a physiological and molecular basis for further study of the migratory behavior of the black cutworm and potential control of this pest.