Some viticulturally relevant neozoans and related indigenous species in the surroundings of vineyards of the southwestern slopes of the Leithagebirge. Part 1: Drosophila suzukii and other Drosophilidae

The neozoan Drosophila suzukii has the ability to develop in fresh, undamaged fruit and therefore is a harmful organism of potentially significant importance for European fruit and wine production. In the present paper the distribution of this species and other Drosophilidae is analyzed in the vineyards, adjoining forest edges and composting plants of the southwestern slopes of the Leithagebirge. In the area investigated, 34 species from six genera of the Dipteran family Drosophilidae were found, 13 of them in the vineyard, 31 in the adjoining forest edges and 17 close to composting plants. However, only species of the genus Drosophila were particularly abundant, especially D. subobscura, D. suzukii, D. obscura, D. melanogaster, D. simulans, D. testacea, D. phalerata, D. immigrans and D. kuntzei. D. subobscura predominantly prevails in the vineyard, abundance of D. suzukii and D. melanogaster is approximately the same. The most abundant species of the forest edges, on the other hand, is D. suzukii, but a similar number of D. subobscura were caught. In the compost, D. testacea and D. immigrans are the most common, but other species are also frequent. D. suzukii and D. melanogaster are relatively insignificant. In total, more Drosophilidae were caught in the compost than at forest edges, least were found in the vineyards. There are no species more abundant in vineyards than at other locations, but some prefer forest edges (D. subobscura, D. suzukii, D. obscura) or composting plants (D. immigrans, D. testacea, D. kuntzei). D. melanogaster, D. simulans and D. phalerata are found frequently both at forest edges and in compost. Whereas most species develop the largest number of individuals in spring and early summer, D. suzukii, D. melanogaster and D. simulans are the most abundant in autumn. A field study comparing the attractiveness of different attractants (grape juices and wines from noble vines and interspecific hybrids, alcohol and vinegar) for D. suzukii and D. melanogaster did not show any significant differences in the response to the attractants.