Research concerning viruses and invertebrate pests is focussing on viruses and their vectors as well as on other important pests on wheat, barley, lupins and rapeseed. These are soil-borne viruses transmitted by Polymyxa graminis, i.e Barley mild mosaic virus (BaMMV) and Barley yellow mosaic virus (BaYMV) with respect to barley or Soil-borne cereal mosaic virus (SBCMV) infecting wheat. With respect to insect transmitted viruses, these are the aphid transmitted Barley yellow dwarf virus (BYDV) and Cereal yellow dwarf virus (CYDV) as well as the leaf hopper transmitted Wheat dwarf virus (WDV). Concerning invertebrate pests, research focuses on resistance of lupins to different aphid species and resistance of wheat to the orange wheat blossom midge (Sitodiplosis mossellana).

Research of this working group is mainly focused on important fungal pathogens of wheat (Triticum aestivum) and barley (Hordeum vulgare). In wheat, these are leaf rust (Puccinia triticina), Fusarium head blight (Fusarium culmorum, Fusarium graminearum) and leaf blotch caused by Septoria tritici. In barley, research is currently conducted on leaf rust (Puccinia hordei), net blotch (Pyrenophora teres) and powdery mildew (Blumeria graminis). In addition, the resistance of rapeseed (Brassica napus) to clubroot (Plasmodiophora brassicae) is analyzed.

No chemical measures are allowed for combating bacterial diseases efficiently, and it is not very likely that they will be available in the near future. Therefore, besides sanitation measures, resistance to bacterial diseases is of special importance. Research focuses on pomaceous fruits and strawberry. These are Erwinia amylovora, the causal agent of fire blight, and Xanthomonas fragariae causing angular leaf spot on strawberry.