The expression profiles of PxEcRs and PxUSP, respectively, during P. xylostella development. Sample collections are detailed in Method section. The mRNA levels were determined by qRT-PCR and normalized to rpL32 reference gene expression. Mean±S.E. represents three independent replications. L1-L4: 1st to 4th larval instar, PP: pre-pupae, P: pupae, A: adult.