Our experiments at the field-site Dahnsdorf focus on long-term field trials. These trials are designed to evolve environmentally sound strategies of cultivation and plant protection. The experiments reflect issues from policy consulting and - as far as possible - take into account issues of societal relevance as well. The opportunities and limitations of pesticide use reduction play an important role in the production of food, feed, energy and raw materials. The determination of the necessary minimum in plant protection has been a main goal since the beginning of the field experiments. Another important issue is to investigate alternative, non-chemical plant protection methods. In addition, biological and alternative crop protection methods for organic farming are tested, especially in potato and winter oilseed rape.
Reliable information in field experiments often need time, sometimes several years, so long-term field trials are of a great value. One of our long-term trials considers the influence of crop rotation (crop rotation compared to continuous cultivation of winter rye), plant protection and fertilisation. The factors fertilisation and plant protection vary in the four stages "without fertilisation / without pesticides", "only pesticides", "only fertilisation" and "with fertilisation and with pesticides" within two crop rotations. This experiment allows to draw several essential conclusions:
In another long-term field trial, we examine how a permanent reduction of pesticides works. This experiment takes also place at two other German locations in Bavaria (Freising) and Lower Saxony (Oldenburg).
Alternative cultivation and plant protection strategies tested at the Institute are evaluated in a holistic way as far as possible by using interdisciplinary approaches: In addition to the review of the pathogens (weeds, fungi and pests) also agronomic factors (grain yield and quality, biomass development), economic aspects (contribution margin, cost without pesticide application) and environmental effects (e.g. risk potential of pesticides, energy demand and greenhouse gas emissions) play an important role.
The long-term field experiments have now lasted for more than 20 years and allow insights into the effects of abiotic stress factors such as extreme weather conditions and their possible interactions with biotic stressors (e.g. presence of pests).