Efficacy of the EPNs (Heterorhabditis bacteriophora) on sugar beet larvae (Bothynoderes punctiventris)

Abstract

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.

Integrated Biological Control of the Sugar Beet Weevil Asproparthenis punctiventris with the Fungus Metarhizium brunneum: New Application Approaches

“…Apart from the use of nematodes [ 27 , 28 ], which were only used against the larvae of the sugar beet weevil A. punctiventris in the soil, this large-scale study is one of the first in almost a hundred years (except a few studies using Beauveria bassiana [ 14 , 15 ]) to test the use of a biologically based insecticide against the weevil pest. We aimed to test the effectiveness of a preventive use of the entomopathogenic fungus Metarhizium brunneum against the weevil in all stages of its development.…”

Olfactory Responses of Asproparthenis punctiventris Germar to Leaf Odours of Amaranthaceae Plants

“…During the subsequent maturation feeding phase, females and males consume sugar beet seedlings or young plants, resulting in their destruction [4][5][6]. The feeding activity can damage entire fields, often requiring reseeding [7,8].…”

“…Recent reports from Poland, Eastern Croatia, and Hungary indicate that the pest has spread further towards Central Europe and become increasingly destructive [2,7,9]. In Eastern Austria, a mass outbreak led to the loss of almost a quarter of the total sugar beet area in 2018, and the sugar beet weevil continued to cause economic damage in subsequent years [8,10].…”

“…Entomopathogenic nematodes [7,13] or entomopathogenic fungi, such as Metarhizium brunneum [14], could be used for the biological control of A. punctiventris. Although these initial studies have confirmed the efficacy of the natural antagonists, more research is needed before they can be used in practice.…”

Suitability of Amaranthaceae and Polygonaceae species as food source for the sugar beet weevil Asproparthenis punctiventris Germar

“…Although this approach succeeded in reducing pest populations, the authors concluded that trapping as an isolated measure is not efficient enough to replace chemical control of the sugar beet weevil. Other alternative measures such as the use of entomopathogenic nematodes as natural enemies for biological control of A. punctiventris have not yet been investigated sufficiently and are not available in practice (Sursuluk 2008;Drmic et al 2020).…”