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Bažok R., Šatvar M., Radoš I., Drmić Z., Lemić D., Čačija M., Virić Gašparić H. (2016): Comparative efficacy of classical and biorational insecticides on sugar beet weevil, Bothynoderes punctiventris Germar (Coleoptera: Curculionidae). Plant Protect. Sci., 52: 134-141.The contact and ingestion activity and the potential of the insecticide spinosad for the control of sugar beet weevil were evaluated and compared with commercially used insecticides lambda-cyhalothrin and chlorpyriphos + cypermethrin. Results of three laboratory trials proved very good efficacy of spinosad applied at the dose of 72 g a.i./ha. Its efficacy was similar to chlorpyriphos + cypermethrin and significantly higher than that of lambda-cyhalothrin. Due to its favourable eco-toxicological properties and good ingestion activity, spinosad is a good candidate to be introduced in the integrated pest management strategy against beet weevil.

The effectiveness of entomopathogenic nematode (EPN) Heterorhabditis bacteriophora Poinar, 1976 (Nematoda: Heterorhabditidae) infective juveniles (IJs) on sugar beet weevil (Bothynoderes punctiventris Germar, 1824 (Coleoptera: Curculionidae)) larvae was investigated during two-year (2014-2015). The field study was conducted to assess EPNs potential for use in practice. In field experiments, three doses of nematodes were used and an untreated control. In the conditions of moderate larval attack (average infestation of 0.28 larvae per plant), EPNs showed clear dose response being highly effective (92.86% control) when applied in the highest dose. Although the results indicated that H. bacteriophora could have a satisfactory mortality effect on sugar beet weevil larvae, further investigations are needed in order to better determine the optimal dose and application timing. If effective, EPNs could be used as one of the tools in a strategy which aims to reduce sugar beet weevil population levels in a wider area.