Institut für Züchtungsforschung an Obst
Woolly apple aphids (Eriosoma lanigerum) are among the most significant pests in fruit production, causing considerable yield losses in both integrated and organic farming. The primary reason is the tissue damage and galls on shoots, which crack open and promote secondary infections, such as apple tree canker (Childs 1929). Additionally, woolly apple aphids cause galls on the roots, which hinder growth by blocking water uptake through the formation of non-conductive xylem from parenchymatic cells, thereby reducing overall water flow (Brown et al. 1991). This pest could significantly contribute to drought stress in affected trees, which is particularly important in light of climate change. Due to increasing restrictions on the approval of synthetic chemical pesticides, controlling this pest is becoming increasingly difficult. The common earwig (Forficula auricularia) is a natural enemy of the woolly apple aphid. With its high feeding capacity of up to 120 aphids per night (Lohrer 2008), the earwig plays a crucial role in biological control and is therefore actively promoted for pest regulation in organic orchards. Due to its omnivorous lifestyle, the targeted introduction and promotion of earwigs could also have positive effects on controlling other pests, such as the green apple aphid, the woolly apple aphid, the codling moth, and scale insects. Similar studies are currently being conducted in a model and demonstration project funded by the Federal Ministry of Food and Agriculture (BMEL) titled "Measures to Strengthen Functional Biodiversity for Sustainable Production in Fruit Growing (FUBIOO)." One focus of FUBIOO is to test the use of earwigs in apple orchards heavily infested with woolly apple aphids. Initial results are promising. The aim of this project is to transfer the scientific findings from FUBIOO into practice and evaluate the effectiveness of controlling woolly apple aphids. It is especially important to establish this beneficial insect in orchards on a long-term basis and to maintain its population over several years. In this context, various types of earwig shelters will be tested for both their effectiveness and durability. The trials will be conducted at three different sites. The Institute for Breeding Research on Fruit Crops at the Julius Kühn Institute (JKI) has 100 years of experience in fruit breeding and has developed varieties that are globally valued for their resistance to diseases, high yields, and versatility. As the coordinator of the German Fruit Gene Bank (DGO), the institute maintains an extensive collection of old apple varieties and other unique genetic resources, which serve as the basis for research and breeding. However, the increasing infestation by woolly apple aphids poses a threat to these valuable collections, making the establishment and evaluation of an effective control method urgently necessary to ensure the sustainable preservation of this genetic diversity.
Erzeugerorganisation Dresdener Obst e.G.
