Bioassay of three biopesticides against Hypera brunneipennis (Boheman) (Coleoptera: Curculionidae) and Monacha obstructa Ferussac. (Moullusca: Helicidae) in the laboratory.

Bahy El-Din, I.A.; Kares, E.A. and El-Khawas, M.A.M.

Abstract

Laboratory studies were conducted to evaluate the toxic effects of three different treatments: the bioinsecticide Biovar (Beauveria bassiana), Andros (Abamectin derivative) and Radiant (Spinosad derivative) on the Egyptian alfalfa weevil Hypera brunneipennis and the terrestrial snail, Monacha obstructa. The LC50 values obtained for the alfalfa weevil, H. brunneipennis were; 7.7641×105 viable spores, 0.9703% and 1.5276% (computed at 6, 2 and one days after treatment). The corresponding LC50 values obtained for the terrestrial snail, M. obstructa were; 5.4995×105 viable spores, 0.5822% and 0.5956% (5, 2 and one days after treatment), for the three tested biopesticides, respectively. The mortality percentages were higher in case of the terrestrial snail than the Egyptian alfalfa weevil. Therefore, using the fungal bioinsecticide Biovar and Andros may be recommended. They could be used side by side with other available safe control methods, when planning for Integrated Pest Management (IPM) strategies against the two tested pests in clover fields.

Key words

Bioinsecticides, Hypera brunneipennis, Monacha obstructa, Bioassay