P. xylostella is a difficult pest to control because of its resistance
to all major classes of insecticides (Furlong et al., 2013) and insec-
ticide mixtures (Attique et al., 2006). Control is often challenging
due to its large host range and lack of natural enemies (Talekar and
Shelton, 1993). Another factor that makes P. xylostella a serious pest
is its high reproductive potential, with more than 20 generations
per year in Guangdong, China (Shelton, 2004).