In vitro effect of the aqueous extract concentrations of the methanol crude extract of Lantana camara flowers and Solanum nigrum fruits were evaluated on the reproduction, feeding response and adult emergence of the potato tuber moth, Phthorimaea operculella. Aqueous extracts of the two tested plants hindered the oviposition of gravid females and hatchability. Moreover, the extracts prevented feeding by newly hatched larvae. The extracts caused a decrease in adult emergence from the treated potato tubers as compared to the control. In addition, bioassay results indicate that the extract of S. nigrum fruits was more effective than the extract of L. camara flowers on the potato tuber moth.