DOK stands for a scientific comparison of cropping systems
Main objective: Development of a basis for decision-makers in politics, associations and society in an interactive platform with farmers and researchers
The following systems are compared:
— D, biodynamic in accordance with Demeter guidelines
— O, bioorganic in accordance with Bio Suisse guidelines (Bud)
— K, conventional (German: konventionell) with farmyard and mineral fertilisers (IP)
— M, conventional with exclusively mineral fertilisation (IP).
Both conventional systems are managed in accordance with the requirements of the Swiss federal government's Proof of Ecological Performance (PEP) programme.
Location: on Birsmattehof farm, Therwil (BL), Switzerland
Trial started: 1978, ongoing
Trial design: In the DOK trial, each cropping system is repeated 12 times so that the spatial variability of the trial field and the annual fluctuations in the weather can be statistically accounted for. The entire trial area measures around 1.3 hectares and includes 96 plots of 100 square metres each.
Implementation: The maintenance of the trial facility and the scientific collection and evaluation of the data is carried out by FiBL Switzerland in collaboration with the Agroscope Reckenholz state research institution.
Key differences: Fertiliser quantity and form, plant protection, biodynamic preparations, growth regulators.
Crop rotation: The current crop rotation includes the following crops: maize, winter wheat, potatoes, soya and grass clover.
Highlight of the DOK trial:
The Swiss State Secretariat for Education, Research and Innovation has included the DOK trial in the Swiss roadmap for research infrastructures, which lists nationally significant trial units. 2002 Publication in Science, cited over 4000 times since then, 142 scientifically peer-reviewed publications.
The DOK trial serves as a model for numerous system comparison trials worldwide.
Compelling scientific evidence for the sustainability of organic
Text: Dr Paul Mäder (FiBL)
In spring 2002, science confirmed what organic farmers had always observed on their farms but could not prove: the three cultivation systems – biodynamic, organic and conventional – differ significantly in terms of soil fertility, climate impact and biodiversity. The groundbreaking results from the comparative trial of different farming systems, which has been running since 1978, were published by FiBL and Agroscope in the top-tier research journal Science. The synthesis of the results was a milestone that led organic farming out of its research niche and increased its credibility – the DOK trial developed international impact.
The DOK trial – D stands for bioDynamic, O for bioOrganic and K for conventional (Konventionell in German) – has grown into a national and international research platform thanks to its practical experimental design and the adaptations made to meet changing requirements over the decades. The best research teams in Switzerland and Europe conduct studies here in various cropping systems. The key topics are long-term yield development, nutrient supply to the soil, soil fertility, climate impact and biodiversity. So far, there have been 142 international publications1 from the DOK trial and many master's and doctoral theses.
The Agroscope Reckenholz agricultural research institute, a federal centre of excellence, and the Research Institute of Organic Agriculture (FiBL) have been working together on the DOK trial in Therwil (Basel-Landschaft) for 46 years. In this long-term study, they are scientifically comparing the agricultural cropping systems commonly used in Switzerland in collaboration with the ETH Zurich and universities.
What makes this special is that the researchers planned the trial together with farmers. Representatives of the three production methods provided ideas and principles for the trial facility. This close collaboration between researchers and farmers, between science and practice, continues to this day and is highly valued by both sides.
Dr Paul Mäder, FiBL
Born 15 July 1954, grew up in Gossau/SG. Dr Phil, Dipl-Ing Agr ETH Zurich, Head of the DOK trial at FiBL from 1987 to 2023. From 1992 to 2022, establishment and management of the Soil and Plant Nutrition Specialist Group, later the Department of Soil Sciences at FiBL. Projects on sustainable agriculture with a focus on soil biology in Switzerland, Europe, India and North Africa. Secretariat of the specialist group for application-based soil biology of the soil protection specialists of the cantons and the Swiss federal government (until 2013). Head of the scientific advisory group for system comparison trials in the tropics (SysCom) until 2024. Guest lecturer at ETH Zurich until 2022 and at the University of Basel until 2024.
