Attractant-baited traps for the sugar-beet weevil Bothynoderes (Cleonus) punctiventris: Preliminary study of application potential for mass trapping

The sugar-beet weevil (Bothynoderes punctiventris Germar) (Coleoptera: Curculionidae) is one of the most important insect pests of sugar-beet throughout central, eastern and southeastern parts of Europe. The damage by the overwintering adult beetles is caused by feeding on sugar-beet seedlings in early spring. As a possible alternative to insecticides, the present research was aimed at studying the potential of traps baited with a synthetic aggregation attractant in decreasing the population of the sugar-beet weevil through mass trapping at the overwintering sites.It was demonstrated that by setting out traps baited with a blend of synthetic (Z)- and (E  )-2-ochtodenal [==Grandlure III–IV; (Z)- and (E)-(3,3-dimethyl)cyclohexylidene)acetaldehyde; the aggregation attractant] at 10 and 30 trap/ha densities, 30–100% of the sugar-beet weevil population was mass-trapped at the overwintering sites. Traps caught non-target beneficial insects in very low numbers. Application of the traps shows good potential as a control method especially at population densities of 30 000 insect/ha or below, and may be capable of decreasing the population pressure of immigrating beetles to sites where sugar-beet is planted in the spring.