Abwehr von Schäden des Erdbeerlaufkäfers, Harpalus pubescens Müll. (Coleoptera, Carabidae), im Erdbeeranbau durch eine Ablenkfütterung1

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Abstract
Protection of strawberries against Harpalus pubescens (Col., Carabidae) by feeding the beetles with averting substances. The strawberry seed beetle Harpalus pubescens Müller is the most frequent carabid besides Pterostichus vulgaris and sometimes injures the strawberry plantations in the region of, Mittelbaden” very much. Experiments on its density and activity carried out in 1971–1973 had comparable results to the findings of Scherney 1959) for other cultural biotops.In feeding‐experiments it could be shown repeatedly that H. pubescens prefers a zoophagous habit. Therefore the change from a zoophagous to a phytophagous habit causing an increased population in the strawberry cultures (where the beetles eat up only the seeds of the berries), must have another reason than a sudden preference of fruit nutrition.The reason for the change of the nutrition habit seems to be the lack of an adequate animalic food for H. pubescens. This seems to be the consequence of the application of chemical control to insects and slugs.A chemical control to H. pubescens is not possible because of different reasons: Its appearance‐time is the flowering period and insecticides would be toxic to honey bees. The non‐toxic insecticides to honey bees have such a long withholding period, that they would cause residues in the fruit. Moreover nearby all natural enemies, the predaceous arthropods, are attacked by chemical control.Therefore, in field experiments during two years a method has been developed to avert the beetles from the strawberry cultures by feeding them with groats of soja beans. By this ”averting‐feeding„ it is possible to keep the damage to the strawberries within a tolerable extend.