In recent studies, equidistant row spacing is discussed as an alternative strategy for the reduction of pesticide use in cropping systems (Wegener et al., 2017). In addition to positive effects on soil erosion and soil water content an earlier canopy closure suppresses weeds (Griepentrog, 1999). The cultivar itself can express different phenotypes in reaction to the plant geometry plasticity (Sultan, 2000). This plasticity is determined in early growth stages mainly by light quality, more specifically by the red: far-red ratio (Zhu et al., 2013).

The main objective of the project is to investigate, if changes in canopy architecture of silage-maize and soybean due to equidistant row spacing can contribute to the reduction of weeds and plant diseases in NOcsPS cropping systems.

Within this project, the following hypotheses will be investigated:

• The optimized stand space per individual plant leads to higher yields due to changes in light quality and light quantity.

• Optimized stand space and changes in plant architecture result in stronger weed suppression.

• In-silico experiments are able to represent correlations of stand distribution and cultivar characteristics (ideotype) to design cropping systems without the use of chemical crop protection measures.

A 3-year exact field trial will be carried out at the agricultural research station of the University of Hohenheim in addition to the cropping system trial. The exact trial will investigate the effect of different equidistant row spacing’s in at least two maize and two soybean cultivars on plant architecture, microclimate as well as occurring weeds and plant diseases.

Based on the collected data on plant architecture, biomass, yield formation and light regimes (PAR, RFR) [R1: Month 24] equidistant row spacings in maize and soybean NOcsPS will be evaluated [. FSPM simulations will be carried out including further changes in sowing density, row distances and cultivar selection etc. with the aim to design NOcsPS and integrate other species (e.g. wheat).