Attract or arrest? Decision making based on population structure analysis

Abstract: Conservation biological control involves manipulation of the environment to
enhance natural enemies’ efficacy. Various types of secondary plants (non-cash crops) were
grown in the agricultural fields to attract and/or maintain natural enemies. However, we cannot determine the function of the secondary plants, i. e., attracting, feeding, and maintaining natural enemies, without knowledge on their movement. In this study, we reviewed the population structure of two natural enemies, the phytoseiid mite Neoseiulus womersleyi and the ladybird beetle Propylea japonica. We conclude that attraction is most important to natural enemies with low migratory distances, and that keeping them in the agricultural fields is the key factor for natural enemies that employ long-range dispersal.