The field research units (FRU) of NAPERDIV are located at four sites across Europe: Sweden (FRU1), Belgium (FRU2), and France (FRU3). This Pan-European feature with its a range of agro-ecological conditions offers a unique opportunity to study the ecological and agronomic performance of the perennial grain crop Thinopyrum intermedium (Kernza®), which is used as model crop and is grown in all four field experiments. These perennial cropping systems are maintained in comparison with annual grain counterparts. This allows for the analysis of different management schemes to answer the explicit research questions and objectives set in the work packages. Moreover, it is a central feature of all FRU (especially FRU4) that they offer great platforms and opportunities for stakeholder engagement and dissemination activities (e.g. field demonstrations).

FRU1 is embedded in the SAFE field experiment and was established in 2016 by the Swedish University of Agricultural Sciences (SLU). SAFE holds in the European context a unique research structure including, amongst others, a perennial grain cropping system with Kernza®. SAFE provides an excellent facility for versatile agroecosystem research. It offers knowledgeable service staff, baseline monitoring programmes, and sampling service, a critical feature to guarantee the self-financed contribution of the Swedish partner. Two systems will be considered in NAPERDIV: The Reference System corresponds to contemporary conventional cereal-dominated crop rotations with use of agro-chemicals. The Perennial System tests Kernza® and is grown with and without the legume Medicago sativa, as well as with no agro-chemicals.

FRU2 is provided by Gembloux AgroBio-Tech (University of Liège) and is located at the experimental farm station in Gembloux (Wallonia, Belgium). This experiment has been established in September 2017 and assesses the effect of different spring/fall nitrogen fertilization regimes and mowing practices on the growth dynamics and agronomic performance of Kernza.

FRU3, as an on-farm experiment, is located in Maubec (near Lyon, Southeast France). This experiment has been established in September 2017. Part of a larger on-farm trial network conducted by ISARA, this field experiment is a chance for testing real-size management options (e.g. weeding, mowing, harvest practices) and measuring overall performance of Kernza® (e.g. biomass, yields, regrowth, longevity). A specific working is dedicated to the analysis of root traits and their interactions with the abundance and diversity of soil microbial communities. This below-ground research approach is currently fostered in a collaboration of research staff between SLU (FRU1) and ISARA, and will be strengthened in NAPERDIV. FRU4 offers additional opportunities for value chain analyses, where grain production of Kernza® is valorised for post-harvest tests and analysis (e.g. grain cleaning, processing, quality).

Location, features and experiments at the field research units (FRU) with IWG cropping (Kernza®) used for NAPERDIV.