The efficacy of three different plant extracts on some biological features of the potato tuber moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) by different application methods

This study tries to apply three plant extracts to protect potato tubers during storage periods, against attacks of the potato tuber moth (Phthorimaea operculella). Bioassays were used to determine the effect of the three selected plants extracts, Ammoides verticillata, Phlomis crinita and Reseda alba, at different concentrations: 0.5%, 1%, 1.5% and 2%. The different biological features and the damage index of potato tubers have been evaluated. In the tuber dipping method, the highest mortality (100%) occurred at the concentration of 2% for the aqueous extract of Ammoides verticillata with (zero) damage index. On the other hand, in the larva dipping method, by the extracts Ammoides verticillata and Reseda alba, the results showed total larval mortality at the highest concentrations, whereas they caused total inhibition of egg hatching at 1% concentration.